Methods for conducting systematic reviews of the evidence of effectiveness and economic efficiency of interventions to reduce injuries to motor vehicle occupants.

BACKGROUND: Motor vehicle occupant injury prevention is included in the Guide to Community Preventive Services because of the enormous health impact of these largely preventable injuries. This article describes the methods for conducting systematic literature reviews of interventions for three key injury prevention strategies: increasing child safety seat use, increasing safety belt use, and decreasing alcohol-impaired driving. METHODS: Systematic review methods follow those established for the Guide to Community Preventive Services and include: (1) recruiting a systematic review development team, (2) developing a conceptual approach for selecting interventions and for selecting outcomes that define the success of the interventions, (3) defining and conducting a search for evidence of effectiveness, (4) evaluating and summarizing the body of evidence of effectiveness, (5) evaluating other potential beneficial and harmful effects of the interventions, (6) evaluating economic efficiency, (7) identifying implementation barriers, (8) translating the strength of the evidence into recommendations, and (9) identifying and summarizing research gaps. RESULTS: The systematic review development team evaluated 13 interventions for the three strategic areas. More than 10,000 titles and abstracts were identified and screened; of these, 277 met the a priori systematic review inclusion criteria. Systematic review findings for each of the 13 interventions are provided in the accompanying articles in this supplement. CONCLUSION: The general methods established for conducting systematic reviews for the Guide to Community Preventive Services were successfully applied to interventions to reduce injuries to motor vehicle occupants.

Reviews of evidence regarding interventions to reduce alcohol-impaired driving.

BACKGROUND: Alcohol-related motor vehicle crashes are a major public health problem, resulting in 15,786 deaths and more than 300,000 injuries in 1999. This report presents the results of systematic reviews of the effectiveness and economic efficiency of selected population-based interventions to reduce alcohol-impaired driving. METHODS: The Guide to Community Preventive Services's methods for systematic reviews were used to evaluate the effectiveness of five interventions to decrease alcohol-impaired driving, using changes in alcohol-related crashes as the primary outcome measure. RESULTS: Strong evidence was found for the effectiveness of .08 blood alcohol concentration laws, minimum legal drinking age laws, and sobriety checkpoints. Sufficient evidence was found for the effectiveness of lower blood alcohol concentration laws for young and inexperienced drivers and of intervention training programs for servers of alcoholic beverages. Additional information is provided about the applicability, other effects, and barriers to implementation of these interventions. CONCLUSION: These reviews form the basis of the recommendations by the Task Force on Community Preventive Services presented elsewhere in this supplement. They can help decision makers identify and implement effective interventions that fit within an overall strategy to prevent impaired driving.

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.

Developing an evidence-based Guide to Community Preventive Services--methods. The Task Force on Community Preventive Services.

Systematic reviews and evidence-based recommendations are increasingly important for decision making in health and medicine. Over the past 20 years, information on the science of synthesizing research results has exploded. However, some approaches to systematic reviews of the effectiveness of clinical preventive services and medical care may be less appropriate for evaluating population-based interventions. Furthermore, methods for linking evidence to recommendations are less well developed than methods for synthesizing evidence. The Guide to Community Preventive Services: Systematic Reviews and Evidence-Based Recommendations (the Guide) will evaluate and make recommendations on population-based and public health interventions. This paper provides an overview of the Guide's process to systematically review evidence and translate that evidence into recommendations. The Guide reviews evidence on effectiveness, the applicability of effectiveness data, (i.e., the extent to which available effectiveness data is thought to apply to additional populations and settings), the intervention's other effects (i.e., important side effects), economic impact, and barriers to implementation of interventions. The steps for obtaining and evaluating evidence into recommendations involve: (1) forming multidisciplinary chapter development teams, (2) developing a conceptual approach to organizing, grouping, selecting and evaluating the interventions in each chapter; (3) selecting interventions to be evaluated; (4) searching for and retrieving evidence; (5) assessing the quality of and summarizing the body of evidence of effectiveness; (6) translating the body of evidence of effectiveness into recommendations; (7) considering information on evidence other than effectiveness; and (8) identifying and summarizing research gaps. Systematic reviews of and evidence-based recommendations for population-health interventions are challenging and methods will continue to evolve. However, using an evidence-based approach to identify and recommend effective interventions directed at specific public health goals may reduce errors in how information is collected and interpreted, identify important gaps in current knowledge thus guiding further research, and enhance the Guide users' ability to assess whether recommendations are valid and prudent from their own perspectives. Over time, all of these advantages could help to increase agreement regarding appropriate community health strategies and help to increase their implementation.

Data collection instrument and procedure for systematic reviews in the Guide to Community Preventive Services. Task Force on Community Preventive Services.

INTRODUCTION: A standardized abstraction form and procedure was developed to provide consistency, reduce bias, and improve validity and reliability in the Guide to Community Preventive Services: Systematic Reviews and Evidence-Based Recommendations (the Guide). DATA COLLECTION INSTRUMENT: The content of the abstraction form was based on methodologies used in other systematic reviews; reporting standards established by major health and social science journals; the evaluation, statistical and meta-analytic literature; expert opinion and review; and pilot-testing. The form is used to classify and describe key characteristics of the intervention and evaluation (26 questions) and assess the quality of the study's execution (23 questions). Study procedures and results are collected and specific threats to the validity of the study are assessed across six categories (intervention and study descriptions, sampling, measurement, analysis, interpretation of results and other execution issues). DATA COLLECTION PROCEDURES: Each study is abstracted by two independent reviewers and reconciled by the chapter development team. Reviewers are trained and provided with feedback. DISCUSSION: What to abstract and how to summarize the data are discretionary choices that influence conclusions drawn on the quality of execution of the study and its effectiveness. The form balances flexibility for the evaluation of papers with different study designs and intervention types with the need to ask specific questions to maximize validity and reliability. It provides a structured format that researchers and others can use to review the content and quality of papers, conduct systematic reviews, or develop manuscripts. A systematic approach to developing and evaluating manuscripts will help to promote overall improvement of the scientific literature.

Methods for systematic reviews of economic evaluations for the Guide to Community Preventive Services. Task Force on 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.

Reviews of evidence regarding interventions to improve vaccination coverage in children, adolescents, and adults. The Task Force on Community Preventive Services.

This paper presents the results of systematic reviews of the effectiveness, applicability, other effects, economic impact, and barriers to use of selected population-based interventions intended to improve vaccination coverage. The related systematic reviews are linked by a common conceptual approach. These reviews form the basis for recommendations by the Task Force on Community Preventive Services (the Task Force) regarding the use of these selected interventions. The Task Force recommendations are presented on pp. 92-96 of this issue.