Chronic fatigue syndrome (CFS) is a debilitating illness [1] that presents unique difficulties for healthcare providers because there are no diagnostic signs, laboratory abnormalities or biomarkers and management aims to improve symptoms; no definitive therapy has been identified. Adding to this, the symptoms comprising CFS are similar to those of many medical illnesses, which must be ruled out [2,3]. Patients with CFS often require multiple office visits and insurance may not cover associated evaluations and lab tests. Further complicating diagnosis and management, some patients perceive skepticism or lack of awareness concerning CFS as a legitimate illness among providers (in particular physicians), which can lead to mistrust and a challenge to patients identity [4,5]. Finally, psychiatric comorbidities (e.g., depression) are common among CFS patients [6] and this poses additional challenges for healthcare providers [3,7].

These problems may in large part explain why only 50% of individuals with CFS have consulted a physician for their illness and fewer than 20% of people with CFS have been diagnosed and treated for the illness [8,9]. Educating providers concerning CFS should improve identification, diagnosis, and management of CFS, but educational activities must be based on providers' current knowledge, attitudes, and beliefs in order to target major current weaknesses. Knowledge, attitudes, and beliefs (KABs) have been studied in the United Kingdom (U.K.), the Netherlands, and Australia, but research in the United States (U.S.) is limited. In the U.K., Raine et al report that primary care physicians feel uncertain or dismissive of CFS, and that these perceptions may pose a barrier to illness management [10]. A separate study reported that despite recent guidelines on CFS management in the U.K. and positive attitudes towards CFS, only 72% of physicians recognized CFS clinically [11]. Bowen et al also reported that 49% of physicians identified the clinical hallmarks of CFS, yet knowledge was not a factor in the self-efficacy of giving a diagnosis [11]. Thomas and Smith found 56% of general practitioners believed CFS as an illness and of this group, 67% reported giving a diagnosis of CFS [12].

In the Netherlands, Scheeres et al showed that physicians informed about CFS reported higher levels of knowledge and better attitudes towards the illness [13]. And, in the same study physicians receiving CFS education were significantly more likely to refer patients for cognitive behavioral therapy compared to physicians who did not receive education [13]. In Australia, 27% of practitioners reported that they did not believe CFS as a syndrome, and yet 71% of the sample stated they had treated a patient for CFS [14]. This study also found that practitioners, who were younger, female, and practiced in small settings, were significantly more likely to accept CFS as an illness. Steven and colleagues state that practitioners who acknowledged CFS as a distinct illness reported more accurate knowledge of CFS (e.g., diagnostic characteristics) and identified appropriate management strategies [14]. One study in the United States did examine attitudes towards treating CFS patients in medical students. However, the study population and small sample size inhibit generalizability to physician populations [15].

We examined KABs about CFS among physicians and other healthcare providers from two different populations in the United States. Our research had three objectives: 1) ascertain awareness of CFS among healthcare providers; 2) assess the knowledge, attitudes, and beliefs related to CFS diagnosis and treatment, and 3) determine where physicians obtain information regarding CFS.

We used convenience and probability sampling methods separately on two different populations regarding knowledge, attitudes, and beliefs concerning CFS by healthcare providers in the United States. In the first sample, we queried a convenience sample of healthcare providers from 13 national-level provider conferences around the country between February 2006 and October 2007. Conferences focused on physicians, nurse practitioners, physician assistants, nurses, or allied health providers and conference size ranged from 1,410 to 7,900 attendees. We staffed a CDC-sponsored CFS education booth in the conference exhibit hall, and for each conference an exhibit booth fee was paid per industry standard. For all conferences we advertised the CFS education booth through advertisements in conference programs, pre-event mailers, and partial conference sponsorships. The education booth displayed and provided free CFS materials such as journal articles, management guidelines, and reference bibliographies and also offered access to free CFS CME courses.

As part of the exhibit, a limited number (75-100 per conference) of USB sticks with CFS educational information were made available to conference participants on a "first-come, first-serve basis." The numbers of USB sticks per conference were decided a priori. In exchange for a USB stick, and to help evaluate the awareness booth activities, conference attendees were asked, but not required, to fill out an anonymous, one-page 12-item CFS KAB form. No identifying information was collected. Permission to dispense USB sticks and collect KAB information was granted by conference organizers and this follows a standard approach used by conference exhibitors.

Content validity of the KAB form was assessed from a pool of questions derived from a panel of experts in CFS research. It included 9 items preliminarily assessing CFS knowledge, attitudes, and beliefs, and 3 questions asking "Have you ever given a diagnosis of chronic fatigue syndrome" (yes, no, or not applicable); "Type of setting do you practice in" (hospital, private practice, group practice, academic, community, or other); and "Type of degree" (doctor of medicine (MD), doctor of osteopathic medicine (DO), nurse practitioner (NP), physician's assistant (PA), registered nurse (RN), occupational therapist (OT), doctor of philosophy (PhD), Masters degree, and other). Respondents could identify more than one practice setting and degree.

Descriptive statistics were reported for the 9 KAB item responses and chi-squared tests were performed to examine their association with giving a diagnosis of CFS. We also analyzed the KAB questions by using exploratory principal components analysis with a varimax rotation. Both a theoretical basis and Suhr's recommendations (variables on same factors share conceptual meanings and variables on different factors differ conceptually) guided variable selection and interpretation of factors [16]. We chose to keep items greater than 0.40 for each factor. The nine KAB questions were measured on scale ranging from 1 = strongly disagree and 7 = strongly agree. A general linear model examined the associations of KAB scales with the factors, CFS diagnosis, practice setting, and type of degree.

In the second sample, probability sampling method was employed through DocStyles, a survey conducted by Porter Novelli (a CDC contractor) in July and August 2006 and 2007. DocStyles is a web-based panel survey developed by Porter Novelli, with input from federal public agencies as well as other profit and non-profit organizations. The CDC submitted questions for the survey in 2006 and 2007. The panel sample stemmed from the Epocrates Honor Panel http://www.epocates.com, consisting of 142,000 verified physicians [17]. A sample is randomly selected from the master database to match the American Medical Association (AMA) files in terms of age, sex, and region, which has information on all physicians in the United States, both members and non-members [18]. This sample was screened to include United States physicians practicing in individual, group, or hospital practices; those in an active practice; and those practicing for the last three years. In 2006, the goal was to recruit 1000 primary care physicians and 250 pediatricians. In 2007, the sample was expanded to also include 250 obstetricians and gynecologists (OB/GYN). Participating physicians received an honorarium, $30 in 2006, and $45 to $55 in 2007, and were not required to participate in the survey and could opt out at anytime.

In 2006, the DocStyles survey contained 41 questions with multiple sub-parts, and in 2007, the survey had 69 questions with multiple sub-parts. There were fifteen CFS questions for both years of the survey. We measured knowledge by asking about CFS symptoms, and attitudes and beliefs by asking agreement to eight statements. Physicians were further asked if they had heard of CFS in the last six months, and if so, from what source the information originated, and if they had ever made a diagnosis of CFS. No personal identifiers were included in the survey and respondents could exit the web survey at anytime. Descriptive and frequency distributions, and chi-square statistics were reported in tables.

We found parallel findings regarding healthcare providers' awareness, knowledge, and diagnosis concerning CFS in both the Conference Healthcare Providers and DocStyles Physicians samples. Over 96% of primary care physicians, pediatricians, and obstetrics/gynecologists in the DocStyles survey reported ever hearing about CFS. In both studies, physicians reported giving a diagnosis of CFS: 64% of conference attendee physicians, and an average of 41% of DocStyles physicians.

A history of prior CFS diagnosis by a healthcare provider or physician impacts the knowledge, attitudes, beliefs, and perceptions of how these professionals view CFS. Forty-one percent of Conference Healthcare Providers reported making a diagnosis of CFS and these respondents were more likely than those who had not made a diagnosis to have a better understanding of the complexities associated with CFS. Similarly, in 2006 and 2007, 46% and 36% of DocStyles Physicians reported giving a diagnosis of CFS and yet 20% of this sample agreed with the statement that "I believe that CFS is all in a patient's head." However, those physicians who had made a diagnosis were significantly less likely to agree with this statement, 66% in 2006 and 85% in 2007, compared to those who did not make a diagnosis, 39% and 64%. These findings are similar to those by Sheeres et al, who found that the more informed physicians are towards CFS, the better the knowledge, attitudes, and beliefs associated with CFS [13].

While additional research is needed to explore why a small percent of physicians who gave a diagnosis still agreed that "CFS is all in the patient's head," one hypothesis is that when physicians have a troublesome experience with a patient, it may skew their attitudes towards CFS and yet allow the diagnostic process to proceed. It must be noted that physicians may have difficulties with a CFS not because of the patient per say, but because the physician finds the diagnostic and management process difficult to navigate.

Physicians in the Conference Healthcare Providers sample had the highest mean score on knowledge compared to nurses, nurse practitioners and physician assistants, occupational therapists, and PhD/Masters. In terms of knowledge, more than 80% of physicians in the DocStyles survey correctly identified the 4 most common CFS symptoms (unexplained fatigue, unrefreshing sleep, impaired memory or concentration, and muscle or joint pain). U.S. physicians as a whole are clearly aware of CFS, knowledgeable about CFS symptoms, and around half have given a diagnosis.

Of all healthcare providers, nurses had the lowest mean knowledge compared to physicians, physician assistants, nurse practitioners, occupational therapists, and the PhD/Masters group. Providers who reported ever giving a diagnosis of CFS scored significantly higher on the knowledge factor compared to those who had not although this association was not statistically significant after the adjustment of physicians' degree and practice setting.

When examining beliefs towards CFS diagnosis and management, physicians, physician assistants, nurse practitioners, occupational therapists, and the PhD/Masters group all scored significantly higher than nurses, which indicates that nurses included in our sample did not have had an informed view of the diagnostic and management issue associated with CFS. Physicians and nurses had significantly higher scores on the attitude factor as compared to nurse practitioners, physician assistants, occupational therapists, and the PhD/Masters group, which indicates a more negative attitude towards CFS. However, all means in the attitudes factor fell between the 25^th and 50^th percentile indicating an overall low negative attitude to CFS among the sample. In the Perception score, physicians had the lowest mean score indicating a good perception of CFS in the population whereas nurses, nurse practitioners, and physician assistants had higher scores although not statistically significant.

Our finding that nurses in the Conference Healthcare Providers sample harbored slightly more negative attitudes and beliefs of CFS and were also less knowledge supports a recent study by Chew-Graham et al, which found that nurses in the United Kingdom had "limited knowledge and experience with clinical features of the illness, its etiology and appropriate management strategies" [[19], p 8]. Nurses in that study were aware of CFS, yet many reported receiving little training concerning the illness and this may account for the discrepancy in awareness versus education. In fact, many CFS education programs target healthcare providers who either diagnose CFS (e.g. physicians or nurse practitioners) or those who assist in management modalities (e.g. cognitive behavioral therapist or occupational therapists). While further research is warranted, CFS education programs aimed at nurses that provide information on the clinical aspects of the illness as well as overall management strategies may be beneficial.

In the United States less than 20% of persons with CFS receive a diagnosis and yet both the Conference Healthcare Providers and DocStyles Physicians respondents reported that an average of 41% of had diagnosed CFS. This finding suggests that persons with CFS may not be aware that assistance is available in the healthcare system in terms of CFS diagnosis and management. It is understandable that patients may delay care because of insurance issues or perceived barriers to healthcare access. Patients need encouragement to seek medical care for CFS symptoms and not concentrate on perceived attitudes and beliefs of providers. However, coupled with this approach, healthcare providers need further guidance on the clinical evaluation, diagnosis, and management strategies for CFS.

When physicians in the DocStyles survey responded to quality of life statements, over 86% of the sample agreed that CFS affects both the patient and the patient's family or caregiver quality of life. This confirms that U.S. physicians recognize the impact of CFS on patients and families. Contrary to existing beliefs, physicians in this sample showed compassion and understanding about CFS issues. In this same study physicians were asked about diagnostic information and treatment options for CFS. Fewer than 30% agreed that enough information was available to make a CFS diagnosis. In terms of treatment options, less than half of physicians agreed there were treatment options for CFS.

The disparity in agreement between acknowledgment that CFS affects quality of life, a high level of awareness, and the ability to recognize the symptoms of CFS versus the inability to recognize that diagnostic and treatment guides are available, point to the need for education programs that provide greater focus on the clinical evaluations and management options and less on raising CFS awareness. Data from both samples demonstrate that while a small percent of healthcare providers are skeptical of CFS and express negative attitudes, the majority of respondents recognize CFS as an illness and understand the impacts it has on society. While physicians in both samples showed high levels of CFS knowledge and appropriate attitude scores, they also demonstrated confusion in how to treat and manage CFS. Future CFS research and educational interventions should incorporate evidence-based behavioral theories with constructs of knowledge, attitudes, and beliefs in the development of programs.

Physicians in the DocStyles survey reported that professional journals, the Internet, and continuing education programs as the top three sources in which they had heard or read about CFS in the past few months. Indeed, the identification of appropriate dissemination and communication channels is extremely important to tailoring information to selected target audiences [20], and so should be taken more advantage of to have an even greater impact on healthcare professionals' awareness of CFS.

The findings begin to fill a gap in the evidence-base concerning knowledge, attitudes, beliefs, and perceptions of U.S. healthcare providers concerning CFS. However, further research concerning CFS KABs among healthcare providers and physicians is needed to assist in developing and delivering educational interventions. Importantly, participants in both samples expressed similar opinions in terms of knowledge, attitudes, and beliefs.

The authors declare that they have no competing interests.

DB drafted the manuscript, participated in study coordination, and helped to conceive the study. FF coordinated parts of the study design and helped to draft the manuscript. JML analyzed the data and contributed to drafting the manuscript. WR conceived of the study, participated in study coordination and helped to draft the manuscript. All authors read and approved the final manuscript.

The pre-publication history for this paper can be accessed here:

http://www.biomedcentral.com/1471-2296/11/28/prepub