The 2016 statistical update from the American Heart Association estimated that the annual cost of cardiovascular disease (CVD) and stroke in 2011–2012 was $193.1 billion in medical care and about $123 billion in lost productivity from premature death.(1) A substantial part of this burden is preventable by preventing and controlling major risk factors for CVD, including hypertension, hypercholesterolemia, and diabetes.(1) Clinical decision support systems (CDSS) are computer-based tools used to assist health providers to prevent and control these risk factors. The Community Preventive Services Task Force (Task Force) recently recommended CDSS for CVD prevention,(2) based on evidence from a systematic review conducted for The Community Guide.(3) The evidence showed CDSS improved screening for CVD risk factors and improved practices for CVD-related preventive care services, clinical tests, and treatments. The objective of the present study is to assess the economic value of CDSS interventions for CVD prevention, based on a systematic review of the literature.

A full description of general methods for Community Guide systematic economic reviews is available online.(4). Briefly, Community Guide systematic economic reviews have the multiple objectives of providing evidence-based estimates of what it costs to implement an intervention, calculating the expected benefits from averted healthcare cost and worksite productivity losses due to reduced morbidity and mortality, and making a judgement of economic value based on estimated cost-benefit or cost-effectiveness. Estimates of economic outcomes generally vary considerably across evaluation studies. Therefore, Community Guide economic review methods attempt to account for the major elements that drive intervention costs and benefits, identified a priori based on information gained from published literature and subject matter experts.

Following the general methods, a systematic review team was constituted for the evaluation of CDSS for CVD prevention, including subject matter experts on CVD and CDSS from various agencies, organizations, and academic institutions together with expert systematic reviewers from The Community Guide branch at CDC. The team worked under the oversight of the Task Force.

CDSS for CVD prevention were defined as computer-based information systems designed to assist healthcare providers, in primary, secondary, and tertiary care settings, implement guidelines and evidence-based practices by providing tailored reminders to conduct or schedule preventive and screening services; assessments of patients’ risk for developing CVD based on their medical history; and alerts when CVD-related physiologic indicators are not at goal. The CDSS interface with the provider occurs at the point of care, based on individual patient data, and assists providers with recommendations for screening, preventive care, and treatment of their patients who have risk factors for CVD such as obesity, inactivity, smoking, hypertension, hyperlipidemia, or diabetes. Improved clinician actions should mitigate these risk factors and ultimately lead to reduced morbidity and mortality from CVD and therefore also improve economic outcomes. The complete definition and analytic framework are available in the published review of effectiveness.(3)

Twenty-one studies from the 7,508 papers screened met inclusion criteria (Figure 1). Seventeen studies(16–28) reported on EHR- or electronic medical record (EMR)-based CDSS, one study(29) piloted a CDSS residing on a stand-alone desktop, one(30) was based on a diabetes registry, and two studies(31–33) covered both EHR-based and registry-based CDSS (two papers(32, 33) reported on the same research and are counted as one study for this review). Table 1 provides an overview of additional characteristics of the included 21 studies. Most of the studies were based in the U.S. (67%) and implemented in clinics (94%), based on trials with a control group (63%) or models based on trials (25%). The studies covered CDSS implemented alone (36%) or in combination with patient reminders/education (18%), or with team-based care (23%), where primary care providers and patients worked together with other providers to improve care and self-management support for patients. Most studies focused on diabetes (47%) as a risk factor, followed by other CVD risks. More than 90% of the studies were published since 2000. Details of the included studies are available online.(34)

A recent symposium concluded(39) that methodologies are yet to be developed that can rigorously evaluate the economic value of health information technologies at the population and national level even though economic value is evident from individual observations of their success at the local and organizational level. The symposium noted the difficulty in transitioning from judgements of economic value at the level of specific implementations to a judgement about the aggregate of the implementations: costs and benefits have to be summed over implementations with different organizational contexts, technologies, functions, outcomes, scales, and scope. This systematic economic review of one type of health information technology, namely CDSS, encountered similar difficulties among others in synthesizing the economic evidence from various implementation instances.

The cost and economic benefit of CDSS implementations from included studies were poorly reported and many studies did not adhere to sound evaluation or accounting practices. Only a few studies provided a complete accounting of cost to develop, implement, maintain, and operate a CDSS. More complete economic evaluations are necessary to obtain reliable estimates for intervention cost across types and sizes of healthcare settings. Reported economic benefits of a CDSS are often determined or guided by the implementation’s disease or risk-factor focus (e.g., hypertension, CVD, diabetes, depression), functionality (e.g., provider prompts, management of orders, disease management), or the implementer’s objective (e.g., containing cost with cheaper drugs or averting hospital re-admissions). However, despite the heterogeneity in the research literature for the focus, functionality, and objective of CDSS implementations, certain guidelines for the evaluation of economic costs and benefits can still be described.

Starting with cost, important features of CDSS from an evaluation perspective are its useful life that generally spans multiple years, and the substantial one-time cost of development and implementation. In addition to the one-time cost, maintaining and operating the CDSS requires technical and medical staff time. The present review estimated intervention cost as the sum of these two components, based on recommended accounting practices and tax rules. Details and references are provided in Appendix 1. Because the cost of a CDSS is generally borne by the practice and may differ by practice size, it is useful to communicate the intervention cost in both per-practice and per-patient terms. Most included evaluation studies did one or the other. An additional advantage of intervention cost measured in per-patient terms is its immediate comparability to healthcare cost and health effects that are generally reported in per-patient terms.

Moving to the benefits side of the evaluation, only those benefits that likely resulted from changes in provider clinical decisions and any consequent change in patient behavior and health should be ascribed to the CDSS implementation. The societal perspective is recommended for economic evaluations to account for all healthcare, regardless of who pays for the various components. It is important to know what impact the CDSS has on total healthcare utilization; following the guidelines prompted by the CDSS may increase outpatient visits and/or medications within primary care but may avert very costly inpatient stays and ER visits in tertiary care. This is not to say a partial perspective is without merit. A primary care study evaluating a CDSS to treat hypertension may report the intervention cost per unit reduction in blood pressure ($/mmHg), a useful statistic for clinic managers.

Evaluations are more complex when one or more additional interventions occur along with the CDSS. Both the intervention cost and economic benefit (including QALY saved) must be ascribable to the CDSS when statements are made about the cost-benefit or cost-effectiveness of CDSS implementations. It is often feasible to estimate the cost of the CDSS and additional intervention(s) separately, but obtaining separate estimates for benefits from the component intervention(s) is likely to be difficult, whether analytically or by study design. For example, in an intervention where team-based care is implemented along with the CDSS, a cost-benefit analysis that included only the cost of CDSS in intervention cost and the combined effect of both team-based care and the CDSS in the benefits would be incomplete. In the absence of complete data, statements about the economic value of the CDSS would have to include appropriate caveats.

Many studies included in this review focused on a single CVD risk factor such as diabetes, high cholesterol, or high blood pressure. Outcomes for lifetime cost per QALY saved or cost-benefit ratios were often modeled based on measured improvements in a single or a few risk factors such as blood pressure, blood glucose, or cholesterol. However, a CDSS for CVD prevention and control would, in practice, be implemented with a multiplicity of functionalities including simple provider and patient reminders for screening and testing, patient risk assessments, and medication and lifestyle counseling recommendations across the range of risk factors and indicators for CVD (and diabetes).

The results presented in the current review are consistent with those found in the broader review of evidence for CDSS implementations for all diseases and conditions.(5, 6) That review found that CDSS/Knowledge Management Systems reduced healthcare cost and produced healthcare cost-savings, but it reached mixed conclusions about cost-effectiveness. Similar to the current review, that review also called for evaluations to standardize the metrics for efficiency and cost.

An overall conclusion cannot be reached about the cost-effectiveness or cost-benefit of CDSS for CVD prevention and control. The evidence on cost and benefit is limited by many estimates that do not account for major components, and mixed evidence when the estimates are reasonably complete. Further, the reported cost and benefit in many studies included the effect of interventions in addition to the CDSS.

The quality of economic evidence for CDSS can improve with more evaluations that acknowledge its capital good features and account for both development and operating cost over its span of useful life.