Jonathan E. Fielding

Evidence-Based Public Health: A Fundamental Concept for Public Health Practice

Despite the many accomplishments of public health, a greater attention to evidence-based approaches is warranted. This article reviews the concepts of evidence-based public health (EBPH), on which formal discourse originated about a decade ago. Key components of EBPH include making decisions on the basis of the best available scientific evidence, using data and information systems systematically, applying program-planning frameworks, engaging the community in decision making, conducting sound evaluation, and disseminating what is learned. Three types of evidence have been presented on the causes of diseases and the magnitude of risk factors, the relative impact of specific interventions, and how and under which contextual conditions interventions were implemented. Analytic tools (e.g., systematic reviews, economic evaluation) can be useful in accelerating the uptake of EBPH. Challenges and opportunities (e.g., political issues, training needs) for disseminating EBPH are reviewed. The concepts of EBPH outlined in this article hold promise to better bridge evidence and practice.

Culturally competent healthcare systems: A systematic review☆

Culturally competent healthcare systems-those that provide culturally and linguistically appropriate services-have the potential to reduce racial and ethnic health disparities. When clients do not understand what their healthcare providers are telling them, and providers either do not speak the clients language or are insensitive to cultural differences, the quality of health care can be compromised. We reviewed five interventions to improve cultural competence in healthcare systems-programs to recruit and retain staff members who reflect the cultural diversity of the community served, use of interpreter services or bilingual providers for clients with limited English proficiency, cultural competency training for healthcare providers, use of linguistically and culturally appropriate health education materials, and culturally specific healthcare settings. We could not determine the effectiveness of any of these interventions, because there were either too few comparative studies, or studies did not examine the outcome measures evaluated in this review: client satisfaction with care, improvements in health status, and inappropriate racial or ethnic differences in use of health services or in received and recommended treatment.

Reviews of evidence regarding interventions to reduce tobacco use and exposure to environmental tobacco smoke.

This report presents the results of systematic reviews of effectiveness, applicability, other effects, economic evaluations, and barriers to use of selected population-based interventions intended to reduce tobacco use and exposure to environmental tobacco smoke. The related systematic reviews are linked by a common conceptual approach. These reviews form the basis of recommendations by the Task Force on Community Preventive Services (TFCPS) regarding the use of these selected interventions. The TFCPS recommendations are presented on page 67 of this supplement.

The effectiveness of early childhood development programs: A systematic review

Early childhood development is influenced by characteristics of the child, the family, and the broader social environment. Physical health, cognition, language, and social and emotional development underpin school readiness. Publicly funded, center-based, comprehensive early childhood development programs are a community resource that promotes the well-being of young children. Programs such as Head Start are designed to close the gap in readiness to learn between poor children and their more economically advantaged peers. Systematic reviews of the scientific literature demonstrate effectiveness of these programs in preventing developmental delay, as assessed by reductions in retention in grade and placement in special education.

The Effectiveness of Limiting Alcohol Outlet Density As a Means of Reducing Excessive Alcohol Consumption and Alcohol-Related Harms

The density of alcohol outlets in communities may be regulated to reduce excessive alcohol consumption and related harms. Studies directly assessing the control of outlet density as a means of controlling excessive alcohol consumption and related harms do not exist, but assessments of related phenomena are indicative. To assess the effects of outlet density on alcohol-related harms, primary evidence was used from interrupted time-series studies of outlet density; studies of the privatization of alcohol sales, alcohol bans, and changes in license arrangements-all of which affected outlet density. Most of the studies included in this review found that greater outlet density is associated with increased alcohol consumption and related harms, including medical harms, injury, crime, and violence. Primary evidence was supported by secondary evidence from correlational studies. The regulation of alcohol outlet density may be a useful public health tool for the reduction of excessive alcohol consumption and related harms.

Health disparities and health equity: the issue is justice.

Eliminating health disparities is a Healthy People goal. Given the diverse and sometimes broad definitions of health disparities commonly used, a subcommittee convened by the Secretarys Advisory Committee for Healthy People 2020 proposed an operational definition for use in developing objectives and targets, determining resource allocation priorities, and assessing progress. Based on that subcommittees work, we propose that health disparities are systematic, plausibly avoidable health differences adversely affecting socially disadvantaged groups; they may reflect social disadvantage, but causality need not be established. This definition, grounded in ethical and human rights principles, focuses on the subset of health differences reflecting social injustice, distinguishing health disparities from other health differences also warranting concerted attention, and from health differences in general. We explain the definition, its underlying concepts, the challenges it addresses, and the rationale for applying it to United States public health policy.

The Effectiveness of Tax Policy Interventions for Reducing Excessive Alcohol Consumption and Related Harms

A systematic review of the literature to assess the effectiveness of alcohol tax policy interventions for reducing excessive alcohol consumption and related harms was conducted for the Guide to Community Preventive Services (Community Guide). Seventy-two papers or technical reports, which were published prior to July 2005, met specified quality criteria, and included evaluation outcomes relevant to public health (e.g., binge drinking, alcohol-related crash fatalities), were included in the final review. Nearly all studies, including those with different study designs, found that there was an inverse relationship between the tax or price of alcohol and indices of excessive drinking or alcohol-related health outcomes. Among studies restricted to underage populations, most found that increased taxes were also significantly associated with reduced consumption and alcohol-related harms. According to Community Guide rules of evidence, these results constitute strong evidence that raising alcohol excise taxes is an effective strategy for reducing excessive alcohol consumption and related harms. The impact of a potential tax increase is expected to be proportional to its magnitude and to be modified by such factors as disposable income and the demand elasticity for alcohol among various population groups.

Attrition in prevention research

Selective attrition can detract from the internal and external validity of longitudinal research. Four tests of selective attrition applicable to longitudinal prevention research were conducted on data bases from two recent studies. These tests assessed (1) differences between dropouts and stayers in terms of pretest indices of primary outcome variables (substance use), (2) differences in change scores for dropouts and stayers, (3) differences in rates of attrition among experimental conditions, and (4) differences in pretest indices for dropouts among conditions. Results of these analyses indicate that cigarette smokers, alcohol drinkers, and marijuana users are more likely to drop out than nonusers, limiting the external validity of both studies. For one project, differential rates of attrition among conditions suggested a possible attrition artifact which will interfere with interpretation of outcome results, possibly masking true program effectiveness. Recommendations for standardizing reports of attrition and for avoiding attrition through second efforts are made.

Methods for Systematic Reviews of Economic Evaluations for the Guide to Community Preventive Services

OBJECTIVES This paper describes the methods used in the Guide to Community Preventive Services: Systematic Reviews and Evidence-Based Recommendations (the Guide) for conducting systematic reviews of economic evaluations across community health-promotion and disease-prevention interventions. The lack of standardized methods to improve the comparability of results from economic evaluations has hampered the use of data on costs and financial benefits in evidence-based reviews of effectiveness. The methods and instruments developed for the Guide provide an explicit and systematic approach for abstracting economic evaluation data and increase the usefulness of economic information for policy making in health care and public health. METHODS The following steps were taken for systematic reviews of economic evaluations: (1) systematic searches were conducted; (2) studies using economic analytic methods, such as cost analysis or cost-effectiveness, cost-benefit or cost-utility analysis, were selected according to explicit inclusion criteria; (3) economic data were abstracted and adjusted using a standardized abstraction form; and (4) adjusted summary measures were listed in summary tables. RESULTS These methods were used in a review of 10 interventions designed to improve vaccination coverage in children, adolescents and adults. Ten average costs and 14 cost-effectiveness ratios were abstracted or calculated from data reported in 24 studies and expressed in 1997 USD. The types of costs included in the analysis and intervention definitions varied extensively. Gaps in data were found for many interventions.

Frequency of worksite health promotion activities.

The first National Survey of Worksite Health Promotion Activities surveyed a random sample of all private sector worksites with 50 or more employees, stratified by number of employers, geographic location, and type of industry. The 1,358 completed interviews constituted a response rate of 83.1 per cent. Of responding worksites 65.5 per cent had one or more areas of health promotion activity with slightly more than 50 per cent of activities initiated within the previous five years. Overall prevalence by type of activity included health risk assessment (29.5 per cent), smoking cessation (35.6 per cent), blood pressure control and treatment (16.5 per cent), exercise/fitness (22.1 per cent), weight control (14.7 per cent), nutrition education (16.8 per cent), stress management (26.6 per cent), back problem prevention and care (28.5 per cent), and off-the-job accident prevention (19.8 per cent). Mean number of activities across all worksites was 2.1 and for worksites with activities, 3.2. Activity frequency increased with worksite size, was highest in the western region (2.34) and lowest in the northeast (1.96), and varied considerably by industry type. The majority of worksites paid the entire cost of these activities.