<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:mml="http://www.w3.org/1998/Math/MathML" article-type="research-article"><?properties manuscript?><front><journal-meta><journal-id journal-id-type="nlm-journal-id">100892005</journal-id><journal-id journal-id-type="pubmed-jr-id">21821</journal-id><journal-id journal-id-type="nlm-ta">J Acquir Immune Defic Syndr</journal-id><journal-id journal-id-type="iso-abbrev">J. Acquir. Immune Defic. Syndr.</journal-id><journal-title-group><journal-title>Journal of acquired immune deficiency syndromes (1999)</journal-title></journal-title-group><issn pub-type="ppub">1525-4135</issn><issn pub-type="epub">1944-7884</issn></journal-meta><article-meta><article-id pub-id-type="pmid">22217681</article-id><article-id pub-id-type="pmc">4676559</article-id><article-id pub-id-type="doi">10.1097/QAI.0b013e3182479077</article-id><article-id pub-id-type="manuscript">HHSPA741889</article-id><article-categories><subj-group subj-group-type="heading"><subject>Article</subject></subj-group></article-categories><title-group><article-title>Operational Research to Improve HIV Prevention in the United States</article-title></title-group><contrib-group><contrib contrib-type="author"><name><surname>Herbst</surname><given-names>Jeffrey H.</given-names></name><degrees>PhD</degrees></contrib><contrib contrib-type="author"><name><surname>Glassman</surname><given-names>Marlene</given-names></name><degrees>PhD, MSW</degrees></contrib><contrib contrib-type="author"><name><surname>Carey</surname><given-names>James W.</given-names></name><degrees>PhD, MPH</degrees></contrib><contrib contrib-type="author"><name><surname>Painter</surname><given-names>Thomas M.</given-names></name><degrees>PhD</degrees></contrib><contrib contrib-type="author"><name><surname>Gelaude</surname><given-names>Deborah J.</given-names></name><degrees>MA</degrees></contrib><contrib contrib-type="author"><name><surname>Fasula</surname><given-names>Amy M.</given-names></name><degrees>PhD, MPH</degrees></contrib><contrib contrib-type="author"><name><surname>Raiford</surname><given-names>Jerris L.</given-names></name><degrees>PhD</degrees></contrib><contrib contrib-type="author"><name><surname>Freeman</surname><given-names>Arin E.</given-names></name><degrees>MPH</degrees></contrib><contrib contrib-type="author"><name><surname>Harshbarger</surname><given-names>Camilla</given-names></name><degrees>PhD</degrees></contrib><contrib contrib-type="author"><name><surname>Viall</surname><given-names>Abigail H.</given-names></name><degrees>MA</degrees></contrib><contrib contrib-type="author"><name><surname>Purcell</surname><given-names>David W.</given-names></name><degrees>JD, PhD</degrees></contrib><aff id="A1">Division of HIV/AIDS Prevention (DHAP), National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA</aff></contrib-group><author-notes><corresp id="cor1">Correspondence to: Jeffrey H. Herbst, PhD, Operational Research Team, Prevention Research Branch, Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Mailstop E-37, Atlanta, GA 30333 (<email>jherbst@cdc.gov</email>)</corresp></author-notes><pub-date pub-type="nihms-submitted"><day>3</day><month>12</month><year>2015</year></pub-date><pub-date pub-type="ppub"><day>15</day><month>4</month><year>2012</year></pub-date><pub-date pub-type="pmc-release"><day>11</day><month>12</month><year>2015</year></pub-date><volume>59</volume><issue>5</issue><fpage>530</fpage><lpage>536</lpage><!--elocation-id from pubmed: 10.1097/QAI.0b013e3182479077--><abstract><p id="P1">The HIV/AIDS epidemic in the United States continues despite several recent noteworthy advances in HIV prevention. Contemporary approaches to HIV prevention involve implementing combinations of biomedical, behavioral, and structural interventions in novel ways to achieve high levels of impact on the epidemic. Methods are needed to develop optimal combinations of approaches for improving efficiency, effectiveness, and scalability. This article argues that operational research offers promise as a valuable tool for addressing these issues. We define operational research relative to domestic HIV prevention, identify and illustrate how operational research can improve HIV prevention, and pose a series of questions to guide future operational research. Operational research can help achieve national HIV prevention goals of reducing new infections, improving access to care and optimization of health outcomes of people living with HIV, and reducing HIV-related health disparities.</p></abstract><kwd-group><kwd>combination prevention</kwd><kwd>HIV/AIDS prevention</kwd><kwd>operational research</kwd><kwd>treatment as prevention</kwd></kwd-group></article-meta></front><body><sec sec-type="intro" id="S1"><title>INTRODUCTION</title><p id="P2">Recent advances have increased the number and kinds of interventions that have demonstrated efficacy for preventing HIV infection. New biomedical interventions&#x02014;including early antiretroviral therapy (ART) for serodiscordant heterosexual couples,<sup><xref rid="R1" ref-type="bibr">1</xref></sup> oral ART as pre-exposure prophylaxis (PrEP) for HIV-negative men who have sex with men (MSM),<sup><xref rid="R2" ref-type="bibr">2</xref></sup> ART in a vaginal microbicide for use by HIV-negative women as topical PrEP,<sup><xref rid="R3" ref-type="bibr">3</xref></sup> and oral ART as PrEP for heterosexual couples<sup><xref rid="R4" ref-type="bibr">4</xref>,<xref rid="R5" ref-type="bibr">5</xref></sup> &#x02014;when combined with efficacious behavioral and structural interventions can potentially turn the tide against the domestic HIV epidemic.<sup><xref rid="R6" ref-type="bibr">6</xref></sup> The increasing focus on using ART treatment as prevention and using different kinds of interventions together are &#x0201c;game changers&#x0201d; for HIV prevention.<sup><xref rid="R7" ref-type="bibr">7</xref>&#x02013;<xref rid="R10" ref-type="bibr">10</xref></sup> Although we have new HIV prevention tools, many organizations face growing operational, technical, and fiscal impediments to realizing the full potential of existing and new prevention strategies. This underscores an urgent need to identify optimal combinations of approaches for addressing HIV prevention at the individual and other levels.<sup><xref rid="R9" ref-type="bibr">9</xref>,<xref rid="R11" ref-type="bibr">11</xref></sup></p><p id="P3">This article argues that operational research (OR; also referred to as operations research) offers promise as a valuable tool for addressing challenges of enhancing planning and implementation of comprehensive HIV prevention programs and the corresponding prevention opportunities they create. We define OR, identify and illustrate areas where OR can make important contributions to HIV prevention, and pose a series of questions for future research on the implementation of behavioral and structural interventions, HIV testing, linkage to and retention in medical care, and ART for treatment and prevention.</p></sec><sec id="S2"><title>THE HIV/AIDS EPIDEMIC IN THE UNITED STATES</title><p id="P4">The annual number of new HIV infections in the United States has remained relatively stable at about 50,000 Americans each year.<sup><xref rid="R12" ref-type="bibr">12</xref>,<xref rid="R13" ref-type="bibr">13</xref></sup> An estimated 1.2 million Americans are living with HIV infection, and this number is expected to increase.<sup><xref rid="R14" ref-type="bibr">14</xref></sup> HIV is among the top 10 leading causes of death for certain age groups and races/ethnicities, particularly African Americans and Latinos aged 15&#x02013;54 years,<sup><xref rid="R15" ref-type="bibr">15</xref></sup> and specific populations (ie, MSM, injection drug users, and transgender persons) continue to be disproportionately affected.<sup><xref rid="R16" ref-type="bibr">16</xref></sup></p><p id="P5">To heighten awareness of, and systematically address, the HIV epidemic, the Office of National AIDS Policy in the White House released the National HIV/AIDS Strategy (NHAS) in 2010.<sup><xref rid="R17" ref-type="bibr">17</xref></sup> NHAS calls for increased cooperation and coordination among federal agencies and state and local partners to achieve the following goals by 2015: reduce the number of people infected with HIV, increase access to care and optimize health outcomes of people living with HIV, and reduce HIV-related health disparities.<sup><xref rid="R11" ref-type="bibr">11</xref>,<xref rid="R12" ref-type="bibr">12</xref></sup> To help the nation meet these goals, the Centers for Disease Control and Prevention (CDC) has adopted a &#x0201c;high-impact HIV prevention&#x0201d; approach that emphasizes delivering combinations of scientifically proven, cost-effective, and scalable interventions to the highest risk populations and geographical areas.<sup><xref rid="R18" ref-type="bibr">18</xref></sup> For this approach to be maximally successful; however, methods are needed to understand the factors that impact program effectiveness, efficiency, scalability, and sustainability over time; and identify strategies needed to enhance and improve program implementation and optimize program value.<sup><xref rid="R18" ref-type="bibr">18</xref>&#x02013;<xref rid="R20" ref-type="bibr">20</xref></sup></p></sec><sec id="S3"><title>OR: CHARACTERISTICS, DEFINITION, AND SCOPE</title><p id="P6">OR has a strong problem-solving focus that emphasizes the identification, implementation, and assessment of strategies to improve program operations in real-world settings.<sup><xref rid="R20" ref-type="bibr">20</xref>&#x02013;<xref rid="R22" ref-type="bibr">22</xref></sup> OR uses a range of methods (eg, descriptive and analytical studies and mathematical modeling),<sup><xref rid="R19" ref-type="bibr">19</xref></sup> but its aim is to increase systematic uptake of research findings and other evidence-based practices into routine service delivery to improve health-related services and outcomes.<sup><xref rid="R23" ref-type="bibr">23</xref></sup> OR has been defined as research that focuses on the implementation of day-to-day activities or operations of specific agencies/organizations, whereas research focusing on widespread dissemination of programs has been designated as implementation research.<sup><xref rid="R20" ref-type="bibr">20</xref></sup> Although the distinctions between OR and implementation research can help articulate the focus and purpose of specific research projects, these 2 areas of research frequently overlap and the terms may be used synonymously.<sup><xref rid="R20" ref-type="bibr">20</xref></sup> For simplicity, we use the term OR to encompass both areas of research. Our framework for OR presented in <xref ref-type="fig" rid="F1">Figure 1</xref> begins with the identification of problems encountered during program implementation. Part of this process involves the formulation of research questions to guide OR efforts. Once the problem is articulated, a solution is proposed and tested. If the solution is determined to be effective, efficient, and sustainable, it is then disseminated more broadly.<sup><xref rid="R21" ref-type="bibr">21</xref>,<xref rid="R22" ref-type="bibr">22</xref></sup></p><p id="P7">Most OR studies in HIV prevention, treatment, and care have been conducted in developing countries due to a pressing need to determine how best to allocate scarce resources among different interventions along the continuum of prevention and care.<sup><xref rid="R22" ref-type="bibr">22</xref>,<xref rid="R24" ref-type="bibr">24</xref>&#x02013;<xref rid="R27" ref-type="bibr">27</xref></sup> In contrast, OR-related activities for domestic HIV prevention have chiefly focused on &#x0201c;moving research into practice&#x0201d; and studying the implementation of evidence-based interventions by service providers.<sup><xref rid="R28" ref-type="bibr">28</xref>&#x02013;<xref rid="R30" ref-type="bibr">30</xref></sup> However, as constraints on domestic HIV prevention resources have grown, OR&#x02019;s potential to maximize the effectiveness of prevention programs has garnered increasing interest and attention.<sup><xref rid="R17" ref-type="bibr">17</xref>,<xref rid="R18" ref-type="bibr">18</xref>,<xref rid="R31" ref-type="bibr">31</xref></sup></p></sec><sec id="S4"><title>OR AND COMPONENTS OF HIGH-IMPACT HIV PREVENTION</title><p id="P8">The criteria used by CDC to identify and define the components of a high-impact HIV prevention approach provides context for our discussion of how OR can strengthen the planning and implementation of biomedical, behavioral, and structural HIV prevention interventions. Specifically, OR should be used to assess and improve upon the cost-effectiveness, scalability, target population coverage, interactions, and synergies among and prioritization of interventions.<sup><xref rid="R18" ref-type="bibr">18</xref></sup> The continuum of HIV prevention services spans from prevention with HIV-negative persons through care and treatment for HIV-positive persons. Thus, the ensuing discussion examines how OR can be used to achieve high-impact prevention within and across continuum elements including behavioral and structural interventions and activities in the testing and treatment cascade (ie, HIV testing, linkage to and retention in medical care, and ART for treatment and prevention).<sup><xref rid="R32" ref-type="bibr">32</xref>,<xref rid="R33" ref-type="bibr">33</xref></sup> Key OR questions are provided (<xref ref-type="table" rid="T1">Table 1</xref>) for improving capacity to deliver prevention programs with the greatest overall potential to reduce HIV infections.</p><sec id="S5"><title>Behavioral and Structural Interventions</title><p id="P9">Behavioral and structural interventions to reduce HIV-related risk behaviors continue to be important components in the domestic portfolio of HIV prevention programs.<sup><xref rid="R18" ref-type="bibr">18</xref></sup> Efficacious individual-level, group-level, and community-level interventions have been shown to significantly reduce risk behaviors associated with HIV acquisition among uninfected persons and transmission among people living with HIV.<sup><xref rid="R34" ref-type="bibr">34</xref></sup> In addition, structural interventions, such as condom distribution and syringe services programs, have led to changes in social norms concerning sex and drug injection behaviors and changes in the behaviors themselves.<sup><xref rid="R35" ref-type="bibr">35</xref>,<xref rid="R36" ref-type="bibr">36</xref></sup> Although the efficacy of these interventions has been demonstrated, significant questions remain about their relative scalability, efficiency, and cost-effectiveness. New OR strategies are needed to identify the most appropriate venues for intervention activities to reach the highest risk populations and determine the impact and sustainability of intervention efforts when implemented in local jurisdictions (<xref ref-type="table" rid="T1">Table 1</xref>). OR also needs to focus on developing interventions essential to the success of high-impact prevention (eg, promoting linkage to care, overcoming barriers to retention and adherence to medical treatment of HIV-infected persons).</p></sec><sec id="S6"><title>HIV Testing in Clinical and Nonclinical Settings</title><p id="P10">HIV testing, linkage to medical care, and initiation of ART are the 3 components of a &#x0201c;test and treat&#x0201d; paradigm for reducing HIV transmission.<sup><xref rid="R37" ref-type="bibr">37</xref></sup> Learning one&#x02019;s HIV serostatus through testing is critical for the subsequent uptake of prevention and treatment services, and HIV testing has been shown to be cost-effective in clinical and nonclinical settings.<sup><xref rid="R38" ref-type="bibr">38</xref>,<xref rid="R39" ref-type="bibr">39</xref></sup> A resource allocation model of CDC funds suggested that targeted HIV screening programs are essential to HIV incidence reduction efforts.<sup><xref rid="R40" ref-type="bibr">40</xref></sup> Although 16&#x02013;22 million Americans test for HIV annually, more than one-fifth of infected persons are unaware of their HIV serostatus,<sup><xref rid="R41" ref-type="bibr">41</xref></sup> and more than one-third of those identified as HIV positive for the first time are diagnosed with AIDS within 1 year of their HIV test.<sup><xref rid="R42" ref-type="bibr">42</xref></sup> Late testing and delayed diagnosis are particularly common among racial/ethnic minority populations.<sup><xref rid="R43" ref-type="bibr">43</xref>,<xref rid="R44" ref-type="bibr">44</xref></sup></p><p id="P11">In an effort to expand access to HIV testing in the United States, CDC funded demonstration projects to determine the feasibility and effectiveness of using conventional and rapid HIV tests in various clinical and nonclinical settings.<sup><xref rid="R45" ref-type="bibr">45</xref></sup> Challenges to expanding the scope of HIV testing included competing priorities for limited resources within clinical settings; logistical difficulties testing large numbers of people in clinical and correctional settings; delivering preliminary positive test results in community-based venues and confirmatory results to transient, homeless and other hard-to-reach populations; and linking persons with HIV infection to care in nonclinical settings.<sup><xref rid="R45" ref-type="bibr">45</xref></sup></p><p id="P12">Many of the implementation challenges highlighted by these demonstration projects and other published studies examining various HIV testing strategies readily lend themselves to OR.<sup><xref rid="R46" ref-type="bibr">46</xref>,<xref rid="R47" ref-type="bibr">47</xref></sup> At a minimum, OR must identify optimal strategies for reaching high-risk persons to increase early detection, receipt of test results, and linkage to medical care. Effective strategies must be developed and disseminated to ensure that persons who receive preliminary test results also receive confirmatory results, to enhance partner services programs to identify new HIV-positive persons, and to strengthen the implementation of self-testing. Moreover, strategies must be developed for improving HIV testing programs at the agency and system levels, including the identification of internal agency structures that improve testing programs. Finally, OR should inform the development of models for allocating testing resources in ways that reinforce and support programs. <xref ref-type="table" rid="T1">Table 1</xref> lists OR questions to address these and other issues.</p></sec><sec id="S7"><title>Linkage to and Retention in Continuous Medical Care</title><p id="P13">Linkage to and retention in care ensures that HIV-infected persons receive life-saving treatment, which also reduces their risk of transmitting HIV to others. A meta-analysis of US-based studies for improving linkage to care found that 69% of HIV-diagnosed persons entered HIV medical care, and of these persons, 72% entered care within 4 months of their diagnosis.<sup><xref rid="R48" ref-type="bibr">48</xref></sup> With regard to retention in care, the same meta-analysis found 59% of persons had multiple HIV medical care visits (follow-up periods ranged from 6 months to 3&#x02013;5 years), retention in care was lower at 26% over longer follow-up periods, and up to 40% of HIV-positive persons were not retained in life-long medical care.<sup><xref rid="R48" ref-type="bibr">48</xref></sup> A mathematical modeling study suggests early entry into and retention in medical care has the potential of reducing viral load levels in the community, thus potentially lowering the HIV transmission rate at the population level.<sup><xref rid="R49" ref-type="bibr">49</xref>,<xref rid="R50" ref-type="bibr">50</xref></sup></p><p id="P14">Despite the personal and public health benefits of early entry into and retention in care, a significant number of HIV-positive persons delay entering or re-entering medical care. Approaches to strengthen both linkage and retention in care include cognitive behavioral approaches, proactive case management, and delivery of services in general health care settings.<sup><xref rid="R51" ref-type="bibr">51</xref>,<xref rid="R52" ref-type="bibr">52</xref></sup> OR studies are needed to determine the optimal mix of structural and behavioral approaches to link newly diagnosed persons into care, identify innovative strategies that reward providers&#x02019; retention efforts (eg, reimbursement models), and improve infrastructure and systems for tracking linkage to identify persons out of care at multiple levels (eg, individual, agency, and community; <xref ref-type="table" rid="T1">Table 1</xref>).<sup><xref rid="R32" ref-type="bibr">32</xref>,<xref rid="R53" ref-type="bibr">53</xref></sup></p></sec><sec id="S8"><title>ART for Treatment and Prevention</title><p id="P15">HIV-infected persons who receive ART experience positive health outcomes and reduced mortality. ART as a prevention strategy had been established since the advent of antiretrovirals,<sup><xref rid="R8" ref-type="bibr">8</xref></sup> with prevention of mother-to-child transmission as a major accomplishment.<sup><xref rid="R54" ref-type="bibr">54</xref></sup> Several clinical trials have demonstrated the prophylactic efficacy of ART to prevent HIV acquisition by uninfected persons. The Preexposure Prophylaxis Initiative trial of high-risk uninfected MSM reported an overall 44% reduction in incident HIV infection, with reductions varying from 21% to 73% depending on adherence level,<sup><xref rid="R2" ref-type="bibr">2</xref></sup> the CAPRISA004 study of ART PrEP as a microbicide in women reported a 39% reduced rate of HIV acquisition,<sup><xref rid="R3" ref-type="bibr">3</xref></sup> and 2 studies of ART PrEP use in heterosexual serodiscordant couples reported preliminary findings of efficacy in preventing new HIV infections.<sup><xref rid="R4" ref-type="bibr">4</xref>,<xref rid="R5" ref-type="bibr">5</xref></sup> However, 2 PrEP studies failed, possibly due to implementation challenges. Meanwhile, the HPTN052 clinical trial of 1763 serodiscordant heterosexual couples has unequivocally demonstrated that treating HIV-infected persons early in their infection resulted in a 96% reduction in the sexual transmission rate of the virus to their uninfected partners.<sup><xref rid="R1" ref-type="bibr">1</xref></sup></p><p id="P16">Regardless of whether ART is used as treatment or as PrEP, adherence to medication regimens is necessary to achieve beneficial effects. Suboptimal adherence can have myriad negative consequences including treatment failure, viral resistance, and increased community viral load through the transmission of resistant strains to noninfected persons.<sup><xref rid="R55" ref-type="bibr">55</xref></sup> Interventions have been developed to increase ART adherence, and CDC recently updated its online &#x0201c;Compendium of Evidence-based HIV Prevention Interventions&#x0201d; to include adherence interventions implemented in clinical and nonclinical settings.<sup><xref rid="R56" ref-type="bibr">56</xref></sup> OR studies are needed to understand and enhance the impact of medical providers on patients&#x02019; adherence behaviors, to determine the best interventions to address patients&#x02019; treatment history and prior ART adherence, and to study how organizational factors, such as collaborative relationships with pharmacies or community-based organizations, can extend or supplement how providers serve their patients (<xref ref-type="table" rid="T1">Table 1</xref>). The use of ART for PrEP has unique challenges. OR is needed to develop effective combinations of interventions and counseling approaches for high-risk HIV-negative populations for which PrEP works, such as MSM.<sup><xref rid="R57" ref-type="bibr">57</xref>,<xref rid="R58" ref-type="bibr">58</xref></sup> In terms of the allocation of HIV prevention resources for PrEP, a critical issue will involve how to prioritize behavioral counseling and risk reduction for persons using PrEP versus those not using PrEP and how to best allocate resources in support of PrEP.</p></sec></sec><sec id="S9"><title>CONCLUSION AND FUTURE DIRECTIONS</title><p id="P17">We have described and illustrated how OR can be useful for clarifying barriers to implementing HIV prevention activities that are likely to have a high level of impact on the HIV/AIDS epidemic in the United States and for identifying strategies to overcome those barriers and improve the effectiveness and efficiency of HIV prevention programs. Sustainable high-impact prevention activities are critical to achieving NHAS goals of reducing new HIV infections, increasing HIV-positive persons&#x02019; access to care, and reducing health disparities.<sup><xref rid="R17" ref-type="bibr">17</xref></sup> Our description of how OR can contribute to improved HIV prevention and service delivery are intended to stimulate thinking on ways to improve the effectiveness and efficiency of the continuum of HIV prevention services including behavioral and structural interventions and the cascade of HIV testing and treatment.</p><p id="P18">Although the opportunities for future research are considerable, particularly important areas for future inquiry include developing appropriate research designs to address specific OR questions; clarifying how OR, monitoring and evaluation, surveillance systems, and quality assurance activities can be used together to improve program performance and impact; and identifying solutions stemming from disparities in HIV-related social determinants, including affordable housing, deteriorated neighborhoods, and insufficient health insurance coverage. OR studies that guide public health policy and inform decision-making at the jurisdiction level concerning the effective allocation of constrained HIV prevention resources are also critical. Although resource allocation models provide idealized scenarios,<sup><xref rid="R40" ref-type="bibr">40</xref></sup> OR studies can help translate modeled scenarios to real-world settings, provide modelers needed data to produce recommendations that better account for and incorporate real-world constraints, and support iterative improvements on allocation recommendations produced by models.</p><p id="P19">Resources for HIV prevention programs will likely continue to be limited. These circumstances increase the need for high-impact programs that are evidence-based, cost-effective, scalable, and sustainable for populations at the highest risk of acquiring and transmitting HIV. As needs vary among geographic areas and populations, OR can be used to identify specific combinations of intervention tools, which are optimally tailored to meet localized needs. Our OR framework (ie, identifying problems, developing solutions, testing solutions, and disseminating effective solutions; <xref ref-type="fig" rid="F1">Fig. 1</xref>) can be applied to any HIV prevention-related program including biomedical, behavioral, or structural.<sup><xref rid="R32" ref-type="bibr">32</xref></sup> As CDC and other federal agencies institutionalize the use of combination approaches that span the HIV prevention continuum, the need for OR will become ever more imperative.<sup><xref rid="R59" ref-type="bibr">59</xref></sup></p></sec></body><back><ack id="S10"><p id="P20">Supported by Centers for Disease Control and Prevention, Atlanta, GA.</p><p id="P21">The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the US Centers for Disease Control and Prevention.</p></ack><fn-group><fn id="FN1" fn-type="conflict"><p id="P22">The authors have no conflicts of interest to disclose.</p></fn></fn-group><ref-list><title>REFERENCES</title><ref id="R1"><label>1</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Cohen</surname><given-names>MS</given-names></name><name><surname>Chen</surname><given-names>YQ</given-names></name><name><surname>McCauley</surname><given-names>M</given-names></name><etal/></person-group><article-title>Prevention of HIV-1 infection with early antiretroviral therapy</article-title><source>N Engl J Med</source><year>2011</year><volume>365</volume><fpage>493</fpage><lpage>505</lpage><pub-id pub-id-type="pmid">21767103</pub-id></element-citation></ref><ref id="R2"><label>2</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Grant</surname><given-names>RM</given-names></name><name><surname>Lama</surname><given-names>JR</given-names></name><name><surname>Anderson</surname><given-names>PL</given-names></name><etal/></person-group><article-title>Preexposure chemoprophylaxis for HIV prevention in men who have sex with men</article-title><source>N Engl J Med</source><year>2010</year><volume>363</volume><fpage>2587</fpage><lpage>2599</lpage><pub-id pub-id-type="pmid">21091279</pub-id></element-citation></ref><ref id="R3"><label>3</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Abdool Karim</surname><given-names>Q</given-names></name><name><surname>Abdool Karim</surname><given-names>SS</given-names></name><name><surname>Frohlich</surname><given-names>JA</given-names></name><etal/></person-group><article-title>For the CAPRISA 004 Trial Group. Effectiveness and safety of tenofovir gel, an antiretroviral microbicide, for the prevention of HIV infection in women</article-title><source>Science</source><year>2010</year><volume>329</volume><fpage>1168</fpage><lpage>1174</lpage><pub-id pub-id-type="pmid">20643915</pub-id></element-citation></ref><ref id="R4"><label>4</label><element-citation publication-type="confproc"><person-group person-group-type="author"><name><surname>Thigpen</surname><given-names>MC</given-names></name><name><surname>Kebaabetswe</surname><given-names>PM</given-names></name><name><surname>Smith</surname><given-names>DK</given-names></name><etal/></person-group><article-title>Daily oral antiretroviral use for the prevention of HIV infection in heterosexually active young adults in Botswana: results from the TDF2 study</article-title><conf-name>Paper presented at: 6th International AIDS Society Conference on HIV Pathogenesis, Treatment, and Prevention (IAS 2011)</conf-name><conf-date>July 17&#x02013;20, 2011</conf-date><conf-loc>Rome, Italy</conf-loc></element-citation></ref><ref id="R5"><label>5</label><element-citation publication-type="confproc"><person-group person-group-type="author"><name><surname>Baeten</surname><given-names>J</given-names></name><name><surname>Celum</surname><given-names>C</given-names></name></person-group><article-title>Antiretroviral pre-exposure prophylaxis for HIV-1 prevention among heteroseuxal African men and women: the Partners PrEP Study</article-title><conf-name>Paper presented at: 6th International AIDS Society Conference on HIV Pathogenesis, Treatment, and Prevention (IAS 2011)</conf-name><conf-date>2011; July 17&#x02013;20</conf-date><conf-loc>Rome, Italy</conf-loc></element-citation></ref><ref id="R6"><label>6</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Shattock</surname><given-names>RJ</given-names></name><name><surname>Warren</surname><given-names>M</given-names></name><name><surname>McCormack</surname><given-names>S</given-names></name><etal/></person-group><article-title>Turning the tide against HIV</article-title><source>Science</source><year>2011</year><volume>333</volume><fpage>42</fpage><lpage>43</lpage><pub-id pub-id-type="pmid">21719662</pub-id></element-citation></ref><ref id="R7"><label>7</label><element-citation publication-type="journal"><article-title>HIV treatment as prevention&#x02014;it works (editorial)</article-title><source>Lancet</source><year>2011</year><volume>377</volume><fpage>1719</fpage><pub-id pub-id-type="pmid">21601691</pub-id></element-citation></ref><ref id="R8"><label>8</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Hammer</surname><given-names>SM</given-names></name></person-group><article-title>Antiretroviral treatment as prevention</article-title><source>N Engl J Med</source><year>2011</year><volume>365</volume><fpage>561</fpage><lpage>562</lpage><pub-id pub-id-type="pmid">21767102</pub-id></element-citation></ref><ref id="R9"><label>9</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Hankins</surname><given-names>CA</given-names></name><name><surname>de Zalduondo</surname><given-names>BO</given-names></name></person-group><article-title>Combination prevention: a deeper understanding of effective HIV prevention</article-title><source>AIDS</source><year>2010</year><volume>24</volume><issue>suppl 4</issue><fpage>S70</fpage><lpage>S80</lpage><pub-id pub-id-type="pmid">21042055</pub-id></element-citation></ref><ref id="R10"><label>10</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Granich</surname><given-names>R</given-names></name><name><surname>Crowley</surname><given-names>S</given-names></name><name><surname>Vitoria</surname><given-names>M</given-names></name><etal/></person-group><article-title>Highly active antiretroviral treatment as prevention of HIV transmission: review of scientific evidence and update</article-title><source>Curr Opin HIV AIDS</source><year>2010</year><volume>5</volume><fpage>298</fpage><lpage>304</lpage><pub-id pub-id-type="pmid">20543604</pub-id></element-citation></ref><ref id="R11"><label>11</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Kurth</surname><given-names>AE</given-names></name><name><surname>Celum</surname><given-names>C</given-names></name><name><surname>Baeten</surname><given-names>JM</given-names></name><etal/></person-group><article-title>Combination HIV prevention: significance, challenges and opportunities</article-title><source>Current HIV/AIDS Report</source><year>2011</year><volume>8</volume><fpage>62</fpage><lpage>72</lpage></element-citation></ref><ref id="R12"><label>12</label><element-citation publication-type="book"><collab>Centers for Disease Control and Prevention</collab><source>HIV Surveillance Report, 2009</source><year>2011</year><volume>21</volume><publisher-loc>Atlanta, GA</publisher-loc><publisher-name>Centers for Disease Control and Prevention</publisher-name><date-in-citation>Accessed October 28, 2011</date-in-citation><comment>Available at: <ext-link ext-link-type="uri" xlink:href="http://www.cdc.gov/hiv/topics/surveillance/resources/-reports/">http://www.cdc.gov/hiv/topics/surveillance/resources/-reports/</ext-link></comment></element-citation></ref><ref id="R13"><label>13</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Prejean</surname><given-names>J</given-names></name><name><surname>Song</surname><given-names>R</given-names></name><name><surname>Hernandez</surname><given-names>A</given-names></name><etal/></person-group><article-title>Estimated HIV incidence in the United States, 2006&#x02013;2009</article-title><source>PLoS ONE</source><year>2011</year><volume>6</volume><fpage>e17502</fpage><pub-id pub-id-type="pmid">21826193</pub-id></element-citation></ref><ref id="R14"><label>14</label><element-citation publication-type="journal"><collab>Centers for Disease Control and Prevention</collab><article-title>HIV surveillance&#x02014;United States, 1981&#x02013;2008</article-title><source>MMWR Morb Mortal Wkly Rep</source><year>2011</year><volume>60</volume><fpage>689</fpage><lpage>693</lpage><pub-id pub-id-type="pmid">21637182</pub-id></element-citation></ref><ref id="R15"><label>15</label><element-citation publication-type="gov"><collab>Centers for Disease Control and Prevention</collab><article-title>WISQARS leading causes of death reports, 1999&#x02013;2007</article-title><year>2010</year><date-in-citation>Accessed November 4, 2011</date-in-citation><comment>Available at: <ext-link ext-link-type="uri" xlink:href="http://webappa.cdc.gov/sasweb/ncipc/leadcaus10.html">http://webappa.cdc.gov/sasweb/ncipc/leadcaus10.html</ext-link></comment></element-citation></ref><ref id="R16"><label>16</label><element-citation publication-type="book"><collab>Centers for Disease Control and Prevention</collab><source>HIV Surveillance Report, 2008</source><year>2010</year><publisher-loc>Atlanta, GA</publisher-loc><publisher-name>Centers for Diseae Control and Prevention</publisher-name></element-citation></ref><ref id="R17"><label>17</label><element-citation publication-type="book"><collab>The White House Office of National AIDS Policy</collab><source>National HIV/AIDS Strategy for the United States</source><year>2010</year><publisher-loc>Washington, DC</publisher-loc><publisher-name>The White House</publisher-name></element-citation></ref><ref id="R18"><label>18</label><element-citation publication-type="book"><collab>Centers for Disease Control and Prevention</collab><source>High-Impact HIV Prevention: CDC&#x02019;s Approach to Reducing HIV Infections in the United States</source><year>2011</year><publisher-loc>Atlanta, GA</publisher-loc><publisher-name>Centers for Disease Control and Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, Division of HIV/AIDS Prevention</publisher-name></element-citation></ref><ref id="R19"><label>19</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Padian</surname><given-names>NS</given-names></name><name><surname>Holmes</surname><given-names>CB</given-names></name><name><surname>McCoy</surname><given-names>SI</given-names></name><etal/></person-group><article-title>Implementation science for PEPFAR</article-title><source>J Acquir Immune Defic Syndr</source><year>2011</year><volume>56</volume><fpage>199</fpage><lpage>203</lpage><pub-id pub-id-type="pmid">21239991</pub-id></element-citation></ref><ref id="R20"><label>20</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Remme</surname><given-names>JHF</given-names></name><name><surname>Adam</surname><given-names>T</given-names></name><name><surname>Becerra-Posada</surname><given-names>F</given-names></name><etal/></person-group><article-title>Defining research to improve health systems</article-title><source>PLoS Med</source><year>2010</year><volume>7</volume><fpage>1</fpage><lpage>7</lpage></element-citation></ref><ref id="R21"><label>21</label><element-citation publication-type="book"><person-group person-group-type="author"><name><surname>Fisher</surname><given-names>A</given-names></name><name><surname>Foreit</surname><given-names>J</given-names></name></person-group><source>Designing HIV/AIDS Intervention Studies: An Operations Research Handbook</source><year>2002</year><publisher-loc>Washington, DC</publisher-loc><publisher-name>Population Council</publisher-name></element-citation></ref><ref id="R22"><label>22</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Zachariah</surname><given-names>R</given-names></name><name><surname>Harries</surname><given-names>AD</given-names></name><name><surname>Ishikawa</surname><given-names>N</given-names></name><etal/></person-group><article-title>Operational research in low-income countries: what, why and how?</article-title><source>Lancet</source><year>2009</year><volume>9</volume><fpage>711</fpage><lpage>717</lpage><pub-id pub-id-type="pmid">19850229</pub-id></element-citation></ref><ref id="R23"><label>23</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Schackman</surname><given-names>BR</given-names></name></person-group><article-title>Implementation science for the prevention and treatment of HIV/AIDS</article-title><source>J Acquir Immune Defic Syndr</source><year>2010</year><volume>55</volume><issue>suppl 1</issue><fpage>S27</fpage><lpage>S31</lpage><pub-id pub-id-type="pmid">21045596</pub-id></element-citation></ref><ref id="R24"><label>24</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Mshana</surname><given-names>GH</given-names></name><name><surname>Wamoyi</surname><given-names>J</given-names></name><name><surname>Busza</surname><given-names>J</given-names></name><etal/></person-group><article-title>Barriers to accessing antiretroviral therapy in Kisesa, Tanzania: a qualitative study of early rural referrals to the national program</article-title><source>AIDS Patient Care STDS</source><year>2006</year><volume>20</volume><fpage>649</fpage><lpage>657</lpage><pub-id pub-id-type="pmid">16987051</pub-id></element-citation></ref><ref id="R25"><label>25</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Reid</surname><given-names>T</given-names></name><name><surname>van Engelgen</surname><given-names>I</given-names></name><name><surname>Telfer</surname><given-names>B</given-names></name><etal/></person-group><article-title>Providing HIV care in the aftermath of Kenya&#x02019;s post-election violence: M&#x000e9;decins Sans Fromtieres&#x02019; lessons learned January&#x02013;March 2008</article-title><source>Confl Health</source><year>2008</year><volume>2</volume><fpage>15</fpage><pub-id pub-id-type="pmid">19055803</pub-id></element-citation></ref><ref id="R26"><label>26</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>van Griensven</surname><given-names>J</given-names></name><name><surname>De Naeyer</surname><given-names>L</given-names></name><name><surname>Uwera</surname><given-names>J</given-names></name></person-group><article-title>Success with antiretroviral treatment for children in Kigali, Rwanda: experience with health center/nurse-based care</article-title><source>BMC Pediatr</source><year>2008</year><volume>8</volume><fpage>39</fpage><pub-id pub-id-type="pmid">18831747</pub-id></element-citation></ref><ref id="R27"><label>27</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Painter</surname><given-names>TM</given-names></name><name><surname>Diaby</surname><given-names>KL</given-names></name><name><surname>Matia</surname><given-names>DM</given-names></name><etal/></person-group><article-title>Women&#x02019;s reasons for not participating in follow-up visits before starting short course antiretroviral prophylaxis for prevention of mother to child transmission of HIV: qualitative interview study</article-title><source>BMJ</source><year>2004</year><volume>329</volume><fpage>543</fpage><pub-id pub-id-type="pmid">15345628</pub-id></element-citation></ref><ref id="R28"><label>28</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Collins</surname><given-names>C</given-names></name><name><surname>Harshbarger</surname><given-names>C</given-names></name><name><surname>Sawyer</surname><given-names>R</given-names></name><etal/></person-group><article-title>The diffusion of effective behavioral interventions project: development, implementation and lessons learned</article-title><source>AIDS Educ Prev</source><year>2006</year><volume>18</volume><issue>suppl A</issue><fpage>5</fpage><lpage>20</lpage><pub-id pub-id-type="pmid">16987085</pub-id></element-citation></ref><ref id="R29"><label>29</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Gandelman</surname><given-names>AA</given-names></name><name><surname>DeSantis</surname><given-names>LM</given-names></name><name><surname>Reitmeijer</surname><given-names>CA</given-names></name></person-group><article-title>Assessing community needs and agency capacity&#x02014;an integral part of implementing effective evidence-based interventions</article-title><source>AIDS Educ Prev</source><year>2006</year><volume>18</volume><issue>suppl A</issue><fpage>32</fpage><lpage>43</lpage><pub-id pub-id-type="pmid">16987087</pub-id></element-citation></ref><ref id="R30"><label>30</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Dolcini</surname><given-names>MM</given-names></name><name><surname>Gandelman</surname><given-names>AA</given-names></name><name><surname>Vogan</surname><given-names>SA</given-names></name><etal/></person-group><article-title>Translating HIV interventions into practice: community-based organizations&#x02019; experiences with the diffusion of effective behavioral interventions (DEBIs)</article-title><source>Soc Sci Med</source><year>2010</year><volume>71</volume><fpage>1839</fpage><lpage>1846</lpage><pub-id pub-id-type="pmid">20926169</pub-id></element-citation></ref><ref id="R31"><label>31</label><element-citation publication-type="gov"><collab>National Institute of Mental Health</collab><article-title>Program announcement 08-166: dissemination, implementation and operational research for HIV prevention</article-title><year>2008</year><date-in-citation>Accessed October 15, 2011</date-in-citation><comment>Available at: <ext-link ext-link-type="uri" xlink:href="http://grants.nih.gov/grants/guide/pa-files/PA-08-166.html">http://grants.nih.gov/grants/guide/pa-files/PA-08-166.html</ext-link></comment></element-citation></ref><ref id="R32"><label>32</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Gardner</surname><given-names>EM</given-names></name><name><surname>McLees</surname><given-names>MP</given-names></name><name><surname>Steiner</surname><given-names>JF</given-names></name><etal/></person-group><article-title>The spectrum of engagement in HIV care and its relevance to test-and-treat strategies for prevention of HIV infection</article-title><source>Clin Infect Dis</source><year>2011</year><volume>52</volume><fpage>793</fpage><lpage>800</lpage><pub-id pub-id-type="pmid">21367734</pub-id></element-citation></ref><ref id="R33"><label>33</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Cohen</surname><given-names>SM</given-names></name><name><surname>Van Handel</surname><given-names>MM</given-names></name><name><surname>Branson</surname><given-names>BM</given-names></name><etal/></person-group><article-title>Vital signs: HIV prevention through care and treatment&#x02014;United States</article-title><source>MMWR Morb Mortal Wkly Rep</source><year>2011</year><volume>60</volume><fpage>1</fpage><lpage>6</lpage></element-citation></ref><ref id="R34"><label>34</label><element-citation publication-type="gov"><collab>Centers for Disease Control and Prevention</collab><article-title>Compendium of evidence-based HIV prevention interventions</article-title><year>2011</year><date-in-citation>Accessed November 6, 2011</date-in-citation><comment>Available at: <ext-link ext-link-type="uri" xlink:href="http://www.cdc.gov/hiv/topics/research/prs/evidence-based-interventions.htm">http://www.cdc.gov/hiv/topics/research/prs/evidence-based-interventions.htm</ext-link></comment></element-citation></ref><ref id="R35"><label>35</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Charania</surname><given-names>MR</given-names></name><name><surname>Crepaz</surname><given-names>N</given-names></name><name><surname>Guenther-Gray</surname><given-names>C</given-names></name><etal/></person-group><article-title>Efficacy of structural-level condom distribution interventions: A meta-analysis of U.S. and international studies, 1998&#x02013;2007</article-title><source>AIDS Behav</source><year>2011</year><volume>15</volume><fpage>1283</fpage><lpage>1297</lpage><pub-id pub-id-type="pmid">20886277</pub-id></element-citation></ref><ref id="R36"><label>36</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Palmateer</surname><given-names>N</given-names></name><name><surname>Kimber</surname><given-names>J</given-names></name><name><surname>Hickman</surname><given-names>M</given-names></name><etal/></person-group><article-title>Evidence for the effectiveness of sertile injecting equipment provision in preventing hepatitis C and human immunodeficiency virus transmission among injecting drug users: a review of reviews</article-title><source>Addiction</source><year>2010</year><volume>105</volume><fpage>844</fpage><lpage>859</lpage><pub-id pub-id-type="pmid">20219055</pub-id></element-citation></ref><ref id="R37"><label>37</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Dodd</surname><given-names>PJ</given-names></name><name><surname>Garnett</surname><given-names>GP</given-names></name><name><surname>Hallett</surname><given-names>TB</given-names></name></person-group><article-title>Examining the promise of HIV elimination by &#x02019;test and treat&#x02019; in hyperendemic settings</article-title><source>AIDS</source><year>2010</year><volume>24</volume><fpage>729</fpage><lpage>734</lpage><pub-id pub-id-type="pmid">20154580</pub-id></element-citation></ref><ref id="R38"><label>38</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Farnham</surname><given-names>PG</given-names></name><name><surname>Hutchinson</surname><given-names>AB</given-names></name><name><surname>Sansom</surname><given-names>SL</given-names></name><etal/></person-group><article-title>Comparing the costs of HIV screening strategies and technologies in health-care settings</article-title><source>Public Health Rep</source><year>2008</year><volume>123</volume><issue>suppl 3</issue><fpage>51</fpage><lpage>62</lpage><pub-id pub-id-type="pmid">19166089</pub-id></element-citation></ref><ref id="R39"><label>39</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Shrestha</surname><given-names>RK</given-names></name><name><surname>Clark</surname><given-names>HA</given-names></name><name><surname>Sansom</surname><given-names>SL</given-names></name><etal/></person-group><article-title>Cost-effectiveness of finding new HIV diagnoses using rapid HIV testing in community-based organizations</article-title><source>Public Health Rep</source><year>2008</year><volume>123</volume><issue>suppl 3</issue><fpage>94</fpage><lpage>123</lpage><pub-id pub-id-type="pmid">19166093</pub-id></element-citation></ref><ref id="R40"><label>40</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Lasry</surname><given-names>A</given-names></name><name><surname>Sansom</surname><given-names>SL</given-names></name><name><surname>Hicks</surname><given-names>KA</given-names></name><etal/></person-group><article-title>A model for allocating CDC&#x02019;s HIV prevention resources in the United States</article-title><source>Health Care Mang Sci</source><year>2011</year><volume>14</volume><fpage>115</fpage><lpage>124</lpage></element-citation></ref><ref id="R41"><label>41</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Campsmith</surname><given-names>ML</given-names></name><name><surname>Rhodes</surname><given-names>PH</given-names></name><name><surname>Hall</surname><given-names>HI</given-names></name><etal/></person-group><article-title>Undiagnosed HIV prevalence among adults and adolescents in the United States at the end of 2006</article-title><source>J Acquir Immune Defic Syndr</source><year>2010</year><volume>53</volume><fpage>619</fpage><lpage>624</lpage><pub-id pub-id-type="pmid">19838124</pub-id></element-citation></ref><ref id="R42"><label>42</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Schwarcz</surname><given-names>S</given-names></name><name><surname>Hsu</surname><given-names>L</given-names></name><name><surname>Dilley</surname><given-names>J</given-names></name><etal/></person-group><article-title>Late diagnosis of HIV infection: trends, prevalence, and characteristics of persons whose HIV diagnosis occurred within 12 months of developing AIDS</article-title><source>J Acquir Immune Defic Syndr</source><year>2006</year><volume>43</volume><fpage>491</fpage><lpage>494</lpage><pub-id pub-id-type="pmid">17031318</pub-id></element-citation></ref><ref id="R43"><label>43</label><element-citation publication-type="journal"><collab>Centers for Disease Control and Prevention</collab><article-title>Late HIV testing&#x02014;34 states, 1996&#x02013;2005</article-title><source>MMWR Morb Mortal Wkly Rep</source><year>2009</year><volume>58</volume><fpage>661</fpage><lpage>665</lpage><pub-id pub-id-type="pmid">19553901</pub-id></element-citation></ref><ref id="R44"><label>44</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Nelson</surname><given-names>KM</given-names></name><name><surname>Thiede</surname><given-names>H</given-names></name><name><surname>Hawes</surname><given-names>SE</given-names></name><etal/></person-group><article-title>Why the wait? Delayed HIV diagnosis among men who have sex with men</article-title><source>J Urban Health</source><year>2010</year><volume>87</volume><fpage>642</fpage><lpage>655</lpage><pub-id pub-id-type="pmid">20186493</pub-id></element-citation></ref><ref id="R45"><label>45</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Heffelfinger</surname><given-names>JD</given-names></name><name><surname>Sullivan</surname><given-names>PS</given-names></name><name><surname>Branson</surname><given-names>BM</given-names></name><etal/></person-group><article-title>Advancing HIV prevention demonstration projects: new strategies for a changing epidemic</article-title><source>Public Health Rep</source><year>2008</year><volume>123</volume><issue>suppl 3</issue><fpage>5</fpage><lpage>15</lpage><pub-id pub-id-type="pmid">19172707</pub-id></element-citation></ref><ref id="R46"><label>46</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Kimbrough</surname><given-names>LW</given-names></name><name><surname>Fisher</surname><given-names>HE</given-names></name><name><surname>Jones</surname><given-names>KT</given-names></name><etal/></person-group><article-title>Accessing social networks with high rates of undiagnosed HIV infection: the Social Networks Demonstration Project</article-title><source>Am J Public Health</source><year>2009</year><volume>99</volume><fpage>1093</fpage><lpage>1099</lpage><pub-id pub-id-type="pmid">19372521</pub-id></element-citation></ref><ref id="R47"><label>47</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Halkitis</surname><given-names>PN</given-names></name><name><surname>Kupprat</surname><given-names>SA</given-names></name><name><surname>McCree</surname><given-names>DH</given-names></name><etal/></person-group><article-title>Evaluation of the relative effectiveness of three HIV testing strategies Targeting African-American Men Who Have Sex with Men (MSM) in New York City</article-title><source>Ann Behav Med</source><year>2011</year><volume>42</volume><fpage>361</fpage><lpage>369</lpage><pub-id pub-id-type="pmid">21818527</pub-id></element-citation></ref><ref id="R48"><label>48</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Marks</surname><given-names>G</given-names></name><name><surname>Gardner</surname><given-names>LI</given-names></name><name><surname>Craw</surname><given-names>J</given-names></name><etal/></person-group><article-title>Entry and retention in medical care among HIV-diagnosed persons: a meta-analysis</article-title><source>AIDS</source><year>2010</year><volume>24</volume><fpage>2665</fpage><lpage>2678</lpage><pub-id pub-id-type="pmid">20841990</pub-id></element-citation></ref><ref id="R49"><label>49</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Granich</surname><given-names>RM</given-names></name><name><surname>Gilks</surname><given-names>CF</given-names></name><name><surname>Dye</surname><given-names>C</given-names></name><etal/></person-group><article-title>Universal voluntary HIV testing with immediate antiretroviral therapy as a strategy for elimination of HIV transmission: a mathematical model</article-title><source>Lancet</source><year>2009</year><volume>373</volume><fpage>48</fpage><lpage>57</lpage><pub-id pub-id-type="pmid">19038438</pub-id></element-citation></ref><ref id="R50"><label>50</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Mugavero</surname><given-names>M</given-names></name><name><surname>Amico</surname><given-names>KR</given-names></name><name><surname>Westfall</surname><given-names>AO</given-names></name><etal/></person-group><article-title>Early retention in HIV care and viral load suppression: implications for a test and treat approach to HIV prevention</article-title><source>J Acquir Immune Defic Syndr</source><year>2011</year><comment>E-published September 20, 2011.</comment></element-citation></ref><ref id="R51"><label>51</label><element-citation publication-type="confproc"><person-group person-group-type="author"><name><surname>Liau</surname><given-names>A</given-names></name><name><surname>Petters</surname><given-names>S</given-names></name><name><surname>Crepaz</surname><given-names>N</given-names></name></person-group><collab>For the HIV/AIDS Prevention Research Synthesis (PRS) Team</collab><article-title>A systematic review of strategies to link and retain persons living with HIV (PLWH) into HIV primary medical care in the United States</article-title><conf-name>Paper presented at: 2009 National HIV Prevention Conference</conf-name><conf-date>August 2009</conf-date><conf-loc>Atlanta, GA</conf-loc></element-citation></ref><ref id="R52"><label>52</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Gardner</surname><given-names>LI</given-names></name><name><surname>Metsch</surname><given-names>LR</given-names></name><name><surname>Anderson-Mahoney</surname><given-names>P</given-names></name><etal/></person-group><article-title>Efficacy of a brief case management intervention to link recently diagnosed HIV-infected persons to care</article-title><source>AIDS</source><year>2005</year><volume>19</volume><fpage>423</fpage><lpage>431</lpage><pub-id pub-id-type="pmid">15750396</pub-id></element-citation></ref><ref id="R53"><label>53</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Christopoulos</surname><given-names>KA</given-names></name><name><surname>Das</surname><given-names>M</given-names></name><name><surname>Colfax</surname><given-names>GN</given-names></name></person-group><article-title>Linkage and retention in HIV care among men who have sex with men in the United States</article-title><source>Clin Infect Dis</source><year>2011</year><volume>52</volume><issue>suppl 2</issue><fpage>S214</fpage><lpage>S222</lpage><pub-id pub-id-type="pmid">21342910</pub-id></element-citation></ref><ref id="R54"><label>54</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Connor</surname><given-names>EM</given-names></name><name><surname>Sperling</surname><given-names>RS</given-names></name><name><surname>Gelber</surname><given-names>R</given-names></name><etal/></person-group><article-title>Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group</article-title><source>N Engl J Med</source><year>1994</year><volume>331</volume><fpage>1173</fpage><lpage>1180</lpage><pub-id pub-id-type="pmid">7935654</pub-id></element-citation></ref><ref id="R55"><label>55</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Palella</surname><given-names>FJ</given-names><suffix>Jr</suffix></name><name><surname>Chmiel</surname><given-names>JS</given-names></name><name><surname>Moorman</surname><given-names>AC</given-names></name><etal/></person-group><article-title>Durability and predictors of success of highly active antiretroviral therapy for ambulatory HIV-infected patients</article-title><source>AIDS</source><year>2002</year><volume>16</volume><fpage>1617</fpage><lpage>1626</lpage><pub-id pub-id-type="pmid">12172083</pub-id></element-citation></ref><ref id="R56"><label>56</label><element-citation publication-type="gov"><collab>Centers for Disease Control and Prevention</collab><article-title>Compendium of evidence-based HIV behavioral interventions: medication adherence chapter 2011</article-title><date-in-citation>Accessed November 20, 2011</date-in-citation><comment>Available at: <ext-link ext-link-type="uri" xlink:href="http://www.cdc.gov/hiv/topics/research/prs/ma-chapter.htm">http://www.cdc.gov/hiv/topics/research/prs/ma-chapter.htm</ext-link></comment></element-citation></ref><ref id="R57"><label>57</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Eaton</surname><given-names>LA</given-names></name><name><surname>Kalichman</surname><given-names>SC</given-names></name></person-group><article-title>Risk compensation in HIV prevention: Implications for vaccines, microbicides, and other biomedical HIV prevention technologies</article-title><source>Curr HIV/AIDS Rep</source><year>2007</year><volume>4</volume><fpage>165</fpage><lpage>172</lpage><pub-id pub-id-type="pmid">18366947</pub-id></element-citation></ref><ref id="R58"><label>58</label><element-citation publication-type="journal"><person-group person-group-type="author"><name><surname>Mansergh</surname><given-names>G</given-names></name><name><surname>Koblin</surname><given-names>BA</given-names></name><name><surname>Colfax</surname><given-names>GN</given-names></name><etal/></person-group><article-title>Preefficacy use and sharing of antiretroviral medications to prevent sexually-transmitted HIV infection among US men who have sex with men</article-title><source>J Acquir Immune Defic Syndr</source><year>2010</year><volume>55</volume><fpage>E14</fpage><lpage>E15</lpage><pub-id pub-id-type="pmid">20859085</pub-id></element-citation></ref><ref id="R59"><label>59</label><element-citation publication-type="book"><collab>Centers for Disease Control and Prevention</collab><source>Program Announcement 10-10181: Enhanced Comprehensive HIV Prevention Planning and Implementation for Metropolitan Statistical Areas Most Affected by HIV/AIDS</source><year>2010</year><publisher-loc>Atlanta, GA</publisher-loc><publisher-name>Centers for Disease Control and Prevention</publisher-name></element-citation></ref></ref-list></back><floats-group><fig id="F1" orientation="portrait" position="float"><label>FIGURE 1</label><caption><p id="P23">Framework of operational research for HIV prevention.</p></caption><graphic xlink:href="nihms741889f1"/></fig><table-wrap id="T1" position="float" orientation="portrait"><label>TABLE 1</label><caption><p id="P24">Examples of High-Impact HIV Prevention Activities and OR Questions to Improve Implementation</p></caption><table frame="hsides" rules="groups"><thead><tr><th align="left" rowspan="1" colspan="1">High-Impact HIV<break/>Prevention Activity</th><th align="left" valign="bottom" rowspan="1" colspan="1">OR Questions</th></tr></thead><tbody><tr><td align="left" valign="top" rowspan="9" colspan="1">Behavioral and structural interventions</td><td align="left" valign="top" rowspan="1" colspan="1">What agency characteristics are predictive of greater capacity to implement EBIs (eg, budget, &#x0201c;age&#x0201d; of agency, type of agency)?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What strategies should be developed to assist agencies to select and adopt appropriate EBIs to meet the prevention needs of specific target populations?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What factors are associated with successful and unsuccessful recruitment and retention into EBIs? Do recruitment and retention challenges vary based on intervention and characteristics of the target population?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How do implementing agencies adapt EBIs to meet the needs of their target population or local setting?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What are the barriers to monitoring and evaluation of EBIs, and what strategies can be used to enhance EBI monitoring and evaluation activities?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How can the implementation of condom distribution programs be improved to increase the number of high-risk persons reached?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What are ideal venues for distributing condoms to specific high-risk populations, including persons living with HIV?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How do agencies use HHS guidance to implement syringe services programs?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How can syringe services programs be integrated with HIV testing and other HIV prevention activities to provide an array of needed services for injection drug users?</td></tr><tr><td align="left" valign="top" rowspan="7" colspan="1">HIV testing in clinical and nonclinical settings</td><td align="left" valign="top" rowspan="1" colspan="1">For HIV testing programs implemented in clinical (eg, hospital emergency rooms, community health centers, and sexually transmitted disease clinics) and nonclinical settings (eg, community-based organizations), what are the most effective strategies for reaching the highest risk persons to yield the greatest HIV seroprevalence (eg, use of new media technology, HIV testing campaigns, mobile vans, testing in new venues such as community colleges and faith-based organizations, self-testing)? Do the most effective strategies vary by risk group or other population/agency characteristics?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How should testing be implemented in different clinical settings so that programs can be sustained in the absence of dedicated public health funds?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What actions can be taken to increase the number of persons tested with acute infection and decrease the number tested with advanced HIV disease (ie, late testers)?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What strategies can agencies employ so persons with preliminary HIV-positive test results return for a confirmatory test?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What HIV testing policies at the program-level, agency-level, or jurisdiction-level are barriers and facilitators to effective HIV testing?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">Given imperfect coverage of routine HIV testing, what types of providers should health departments focus on to encourage and support implementation and uptake?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">Given a fixed budget for HIV testing, does it make more sense for health departments to directly fund or provide HIV testing or focus on training for clinical providers to implement routine HIV testing?</td></tr><tr><td align="left" rowspan="7" valign="top" colspan="1">Linkage to and retention in continuous medical care</td><td align="left" valign="top" rowspan="1" colspan="1">How can HIV testing programs effectively track client referrals to ensure successful linkage to care?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What is the best mix of structural and behavioral approaches to link into medical care newly diagnosed HIV-positive persons and HIV-positive persons who have not received care?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How can effective partnerships be established among HIV testing programs, linkage case managers, and HIV clinicians to increase rates of persons linked to and engaged in medical care?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What are the most efficient strategies for linking newly diagnosed clients to medical care (eg, behavioral counseling, cross-training HIV prevention counselors, education and support, and use of case managers and patient navigators)?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How can ancillary services (eg, childcare services, mental health, and substance abuse treatment programs) be used to enhance retention in care and how should they be prioritized and allocated to maximize public health impact?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How can or should health departments use viral load and surveillance data to (1) identify persons not linked to and retained in care, and (2) support reengagement in care?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">Given resource limitations, how should health departments and providers prioritize for outreach and reengagement in care efforts?</td></tr><tr><td align="left" valign="top" rowspan="7" colspan="1">ART for treatment and prevention</td><td align="left" valign="top" rowspan="1" colspan="1">What are the most effective strategies that result in consent for early ART (eg, peer navigators, streamline HIV testing with linkage to care)?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What factors should clinicians or CBOs consider when selecting interventions to improve medication adherence among clients? How can adherence interventions be adapted to address individual patient needs? How often should adherence be assessed?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What are the optimal settings (clinical versus nonclinical) and providers (clinicians versus community-based providers/peers) for delivering ART adherence interventions?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What models can clinical care teams and community providers work with to synergistically support adherence?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">What types of risk-reduction messages (eg, promotion of consistent condom use) should be delivered by clinicians to high-risk clients using PrEP to reduce risk behaviors?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How should PrEP be integrated within existing evidence-based interventions and other medical or social services to form a comprehensive HIV prevention program?</td></tr><tr><td align="left" valign="top" rowspan="1" colspan="1">How should health departments and CBOs prioritize support for PrEP users versus high-risk persons and populations without access to or use of PrEP?</td></tr></tbody></table><table-wrap-foot><fn id="TFN1"><p id="P25">ART, antiretroviral therapy; CBO, community-based organization; EBI, evidence-based behavioral intervention; PrEP, preexposure prophylaxis.</p></fn></table-wrap-foot></table-wrap></floats-group></article>