Welcome to The Community Guide! Let us know what you think of the website by completing this quick survey.
Abstraction/Abstracting Data – The process of collecting data from studies for a systematic review. Data are typically summarized using a standard abstraction form [PDF - 452 kB]. The principles are similar to those of primary data collection, except that information is collected from studies rather than people.
Analytic Framework – A diagram that shows hypothesized links between an intervention and related intermediate outcomes, health outcomes, and other effects. An analytic framework expands on a specific portion of a logic model and is used to plan evaluations of interventions and to guide the search for evidence. (See also Logic Model)
Analytic Horizon – The period of time over which costs and outcomes accrue and are measured after an intervention ends.
Applicability – A judgment about the populations and/or settings in which a recommended activity could be implemented successfully, based on the populations and settings represented in the studies reviewed and conceptual information about the intervention. The Community Guide provides information on applicability for all recommended activities.
Archived – Reviews and findings are archived when they have been updated and replaced with more recent evidence. Findings that have been archived can only be accessed from the summary pages of the updated reviews.
Arm(s) – See study arm(s).
Benefits – Gainful outcomes brought about by an intervention, which promote well-being of an individual or community.
Benefit-to-Cost Ratio – A measure, from a cost-benefit analysis, of the total benefits (or of the benefits within a defined scope, such as individual benefits) of an intervention divided by the total costs, where both benefits and costs are expressed in dollars.
Body of Evidence – The complete set of qualifying studies in a Community Guide systematic review.
Candidate Study – A study that has met the inclusion criteria.
Clinical Preventive Services – Screening, vaccination, counseling, or other preventive services delivered to one patient at a time by a healthcare practitioner in an office, clinic, or healthcare system (See also Community Preventive Services).
Clinical Setting – Setting in which the primary purpose is the delivery of medical care in a one-on-one provider-patient relationship. Can include private office practices, managed care facilities (e.g., HMOs, PPOs, community health centers), clinics, or hospitals. (See also Community Setting.)
Community – A group of individuals sharing one or more characteristics such as geographic location (e.g., a neighborhood), culture, age, or a particular risk factor. In the Guide to Community Preventive Services, for the purposes of evaluating whether interventions make communities healthier, we have chosen to apply the broadest possible use of “community.”
Community Guide – The Guide to Community Preventive Services.
Community Preventive Services – Interventions that provide or increase the provision of preventive services such as screening, education, counseling, or other programs to groups of people, in community settings or healthcare systems (See also Clinical Preventive Services)
Community Preventive Services Task Force (The Task Force) – A 15-member non-federal panel initiated in 1996 by the Director, Centers for Disease Control and Prevention (CDC), under the auspices of the U.S. Public Health Service. The mission of this task force is to carry out systematic reviews of prevention intervention that can be carried out in communities, and to develop recommendations based on the findings of these reviews. The Task Force findings are presented in the Guide to Community Preventive Services (the Community Guide). (See also U.S. Preventive Services Task Force)
Community Setting – Setting for which the primary purpose is not medical care, for example, geographic communities, schools, churches, homeless shelters, worksites, libraries. (See also Clinical Setting.)
Community-Based Intervention – An intervention conducted within and by members of a particular community (e.g., grassroots efforts, efforts by a local civic group). Can be done in conjunction with an outside group (e.g., nonprofit organization, research group).
Community-Oriented Intervention – An intervention meant to improve the health or reduce injury or impairment of people in a community. Community-oriented interventions include but are not limited to community-based interventions.
Comparison Group – A group that is not exposed to a particular intervention; changes in this group are used to estimate what would have happened if the intervention had not been carried out. In experimental studies, such as Randomized Controlled Trials (RCT), the comparison group is generally referred to as the control group.
Considered Study – In a Community Guide systematic review, a study or article that is retrieved from the list of screened titles and abstracts because it may meet review inclusion criteria. Each considered study that meets the criteria for inclusion in the review becomes a candidate study.
Consultants, Consulting Team – A group of 10–30 people, with special knowledge in the field under review, who work in consultation with the coordination team, providing opinion and expertise in support of a systematic review.
Coordination Team – The group of 6-10 people that directs the Community Guide systematic review. Also referred to as the review team, development team, or systematic review development team. These teams typically include subject matter experts, a Task Force member, an economist, a research assistant, and others with special knowledge of the subject.
Cost Analysis – An economic evaluation technique that involves the systematic collection, categorization, and analysis of program costs.
Cost-Benefit Analysis – A type of economic evaluation that measures both costs and benefits (i.e., negative and positive consequences) associated with an intervention in dollar terms.
Cost-Effectiveness Analysis – An analysis used to compare the cost of alternative interventions that produce a common health effect (e.g., cost per injury averted or life year saved).
Costs – The value of resources (people, buildings, equipment, and supplies) used to produce a good or service.
Cost-Saving – An intervention, program, or policy is said to be cost-saving if the costs averted by the intervention exceed the costs of the program.
Cost-Utility Analysis – A type of cost-effectiveness analysis that uses life years saved adjusted for quality of life during those years as a health outcome measure. These measures are called Quality Adjusted Life Years (QALYs).
Determinants – Causal factors hypothesized to affect health outcomes. Determinants can refer to such factors as demographic and population (host) factors; environmental factors, such as disease vectors or transmission agents (e.g., food or water); social, economic, educational, healthcare, cultural, or other systems; and preventive interventions.
Econometric Methods – Applying statistical methods to the study of economic data.
Economic Benefit – Monetized value of averted healthcare cost or productivity loss.
Economic Costs – The value of resources, including opportunity costs, often used to compare alternative interventions.
Economic Efficiency – Achieving the greatest improvement in health using the available resources.
Economic Evaluation – An assessment of the economic impact of an intervention, program, or policy.
Effect – The change in an outcome that results from an intervention.
Effect Measure – The outcome measurement used to assess the effect.
Effect Modifier – A factor with the potential to modify the effect of an intervention. Effect modifiers may be related to characteristics of the population, the setting, the study, intervention implementation, or other relevant aspects.
Effect Size/Estimate – The estimated magnitude of the effect.
Effectiveness – The degree to which an intervention achieves a desired outcome in practice.
Effects, Other – See Other Effects.
Evidence-Based Method – A strategy for explicitly linking public health or clinical practice recommendations to scientific evidence of the effectiveness and/or other characteristics of such practices.
External Validity – The degree to which study results generalize to populations and contexts beyond the particular ones included in the studies themselves.
Financial Costs – The actual dollar costs for services, typically the actual costs of care.
Grey Literature – Grey literature is information that has not been published or that, although published, cannot be found through readily accessible sources. Grey literature can take many forms across multiple disciplines, including conference proceedings, theses and dissertations, research and technical reports, census information, and ongoing research.
Guide to Clinical Preventive Services (Clinical Guide) – The clinical counterpart to the Guide to Community Preventive Services, prepared and published by the U.S. Preventive Services Task Force (USPSTF) . The Clinical Guide, widely used by primary care providers, health policy makers, and others, provides current and scientifically defensible information from published clinical research on the effectiveness of different preventive services and the quality of evidence upon which conclusions are based.
Guide to Community Preventive Services (Community Guide) – The body of evidence and Community Preventive Services Task Force findings published in scientific journals and presented on this website.
Harms – Adverse other effects, either possible or documented, brought about by an intervention.
- Major Harms – Direct harms that, in the opinion of the coordination team and Task Force, outweigh the potential benefits of the intervention.
- Minor Harms – Direct harms that, in the opinion of the coordination team and Task Force, represent less serious harms of an intervention.
Health – Positive physical, mental, psychological, and social function and the absence of disease, injury, or impairment.
Health Indicator – A measure of the health of people in a community, such as infant mortality rates, rates of obesity, or incidence of diabetes.
Health Outcome – A measure of health or loss of health that assesses one or more of the following factors:
- Mortality (rates of death, years of potential life lost, quality adjusted life years gained, disability adjusted life years lost)
- Morbidity (disease or injury rates, infertility rates, disability, chronic pain, functional status, psychiatric disorders, etc.)
- Positive measures of health (e.g., measures of well-being, physical, social or occupational function)
- Pregnancy and birth rates
- (See also Outcomes, Intermediate Outcomes, and Recommendation Outcomes)
Healthcare Providers – Individuals from any of several professional groups (e.g., physicians, nurses, and others) who provide direct healthcare services to individual clients or patients.
Healthcare Systems – Systems for delivering healthcare that may include, for example, hospitals, clinics, health maintenance organizations (HMOs), and community health centers.
High Income Economy – Countries with high income economies as defined by the World Bank .
Inclusion Criteria – Characteristics of a study that make it appropriate for inclusion in a particular Community Guide systematic review. A study that is included is referred to as a candidate study; it must also meet the quality criteria before it can become part of the body of evidence.
Inactive – Reviews and findings that are inactive are not scheduled for an update at this time, though they may be updated in the future. Findings become inactive when reviewed interventions are no longer commonly used, when other organizations begin systematically reviewing the interventions, or as a result of conflicting priorities within a topic area. Task Force findings considered inactive can be accessed through the search engine.
Insufficient Evidence to Determine Effectiveness – A body of evidence that does not provide enough information for the Task Force to determine whether or not an intervention is effective. A finding of insufficient evidence indicates the need for additional research into the effectiveness of the intervention; it does not mean that the intervention doesn’t work, but rather that we can’t tell yet if it works. The requirements for insufficient evidence are set forth in the translation table.
Intermediate Outcome – Variable that occurs in the causal pathway between an intervention or determinant and the final health outcome, such as:
- Levels of risk behaviors
- Rates of access to, usage of, and coverage of preventive services
- Physiologic measures (e.g., blood pressure or cholesterol levels)
- Levels of environmental exposure
- (See also Outcomes, Health Outcomes, and Recommendation Outcomes)
Internal Validity – The degree to which the intervention being evaluated really caused the effects estimated in a study.
Intervention – In the Community Guide, an intervention is any kind of planned activity or group of activities (including programs, policies, and laws) designed to prevent disease or injury or promote health in a group of people, about which a single summary conclusion can be drawn.
Intervention, Multicomponent – An intervention that includes more than one distinct activity. For example, mass media campaigns to motivate young people to remain tobacco-free can be combined or coordinated with additional intervention activities, such as increases in tobacco product excise taxes, school-based education, and other community-wide activities.
Intervention Arm – See Study Arm.
Intervention Group – A group of people exposed to an intervention. (See also Comparison Group.)
Life Years Saved – A measure of the improvement in health based on the number of affected individuals multiplied by the number of years each individual is expected to live.
Logic model – A diagram that illustrates the public health context in which a specific disease prevention or health promotion activity takes place. Logic models show relationships between social, environmental, and biological determinants and outcomes, and strategic points at which action can be taken to change the outcome. (See also Analytic Framework)
Lumping – Grouping studies together for analysis, because a logical argument can be made for considering the study results together. For example, studies evaluating the effectiveness of a particular intervention in increasing screening for breast, cervical, and colorectal cancer could be lumped together or they could be studied separately. In Community Guide systematic reviews, the decision to lump (or split) studies is made by the coordination team with approval of the Task Force (see also Splitting).
Meta-Analysis – A quantitative approach in which individual study findings addressing a common problem are statistically integrated and analyzed to determine the effectiveness of interventions.
Meta-Regression – A statistical technique using linear or logistic regression to assess how characteristics of the intervention, population, context, or study relate to effect size.
Multicomponent Intervention (See Intervention, Multicomponent)
Net Benefit – A measure from a cost-benefit analysis, calculated as the value of the benefits gained minus the costs.
Net Cost – The total program costs minus the cost of averted disease and the cost of averted productivity losses.
Opportunity Costs – The value of the alternatives given up in order to use the resource as the program so chooses.
Other Effects – Side effects of an intervention not already included in the assessment of effectiveness. These may relate to health or non-health outcomes and may include harms or benefits as well as effects that are intended or not.
- Direct Other Effects – Other effects that are a direct consequence of the implementation of a specific intervention.
- Indirect Other Effects – Other effects that are a consequence of the changes in targeted behavior or condition (i.e., the recommendation or health outcomes) in response to an intervention.
- Documented Other Effects – Direct other effects which are documented and supported by a body of evidence fulfilling Community Guide criteria for assessing effectiveness.
- Possible Other Effects – Other effects generated by the coordination teams or discussed in the literature but not yet adequately documented based on available empirical evidence.
Percent (%) Change – A change expressed with the percent (%) symbol represents a relative difference. For example, if 50% of participants had already quit smoking at the beginning of the study, a 10% improvement over this baseline would result in a total of 55% who had quit (the 50% baseline plus 10% of that baseline, which is 5%).
Percentage Point Change – A percentage point change represents an absolute difference. For example, if 50% of participants had already quit smoking at the beginning of the study, an increase of 10 percentage points would mean that a total of 60% had quit at the end of the study (because 50% + 10 percentage points = 60%).
Perspective – The viewpoint according to which the costs and benefits of an intervention are calculated or estimated (e.g., society, government, healthcare providers, business, or patients).
Policy – A set of organizational rules (including but not limited to laws) intended to promote health or prevent disease.
Preventive Service – An intervention (activity) that prevents disease or injury or promotes health. In Community Guide documents, "preventive services" and "interventions" are used interchangeably.
Productivity Loss – Costs associated with the decrease in production and income attributable to a disease, disability, or death.
Proxy Outcome – An outcome which is not the ultimate outcome of interest, but which has been shown to be a reasonable proxy for that outcome. A proxy outcome would be used when the outcome of interest cannot feasibly be calculated. For example, measures of alcohol involvement in fatal vehicular crashes are limited, so a number of proxy outcomes (e.g., nighttime fatal crashes, all fatal crashes, and others) may be assessed instead to determine whether the intervention is effective.
Public Health Practitioners – People responsible for providing public health services, regardless of the type of organization in which they work. They may work in a variety of occupational categories, in public health agencies, managed care organizations, community health centers, or academic institutions.
QALY or Quality-Adjusted Life Year – A health outcome that combines the years of life with the quality of life experienced during those years, relative to quality associated with perfect health.
Qualifying Studies – In a Community Guide systematic review, all studies that meet the inclusion criteria are then rated on the quality of the study design and execution. Studies that meet these quality criteria become the qualifying studies for that review.
Quality Criteria – Characteristics related to design and execution of studies that are used by a coordination team to establish the utility of a study for answering key review questions related to intervention effectiveness
Quality of Execution – Studies are assessed to have good, fair, or limited quality of execution. This is based on six characteristics (i.e., descriptions of the study population and the intervention, sampling of the study population, measurement of exposures and outcomes, data analysis, interpretation of results, and other threats that have not already been addressed in the other categories) and the limitations associated with each, as defined by the Community Guide. Quality of execution can affect our confidence that the intervention being evaluated really caused the effects or outcomes being measured (internal validity) or our confidence that the study results can be generalized to populations and contexts beyond the particular ones included in the studies themselves (external validity). Read more >> [PDF - 6.80 MB]
Recommendation Outcome – An outcome on which the Task Force will base a recommendation, usually either a health outcome or a well established proxy for a health outcome. Decisions about which outcomes will be recommendation outcomes are made at the beginning of a review by members of the coordination team and the Community Preventive Services Task Force. (See also Outcomes, Intermediate Outcomes, and Health Outcomes)
Screened/Screening – The process of reading article titles and abstracts obtained through a literature search, to determine which articles may be relevant to the review. All screened articles are then retrieved for further consideration. (See also Considered Study)
Search Parameters – Factors determined before a search is executed and used to decide what to include in the search. Such factors can relate to keywords, language in which the article is published, country in which the study was conducted, and when the study was conducted.
Sensitivity Analysis – A technique to assess how estimated outcomes vary with a change in the key assumptions on which they are based.
Splitting – Creating two or more subgroups of studies for analysis, because the larger group contains a variety of distinct and potentially relevant differences. For example, studies evaluating the effectiveness of a smoking cessation program might be split into programs conducted at worksites and those conducted through healthcare systems. In Community Guide systematic reviews, the decision to split (or lump) studies is made by the review team with approval of the Task Force (see also Lumping).
Strong Evidence of Effectiveness – A body of evidence that provides enough information for the Task Force to determine whether an intervention is effective. The requirements for strong evidence are set forth in the translation table.
Studies Included in Effect Estimate Calculations – The number of included studies that reported an outcome using comparable metrics or measurements.
Study Arm(s) – In a study in which two or more groups are compared, each group that receives an intervention is an arm. For the purposes of reporting results of a Community Guide review, study arms may refer to:
- Groups that receive different types or levels of interventions
- An intervention applied to groups that differ by location or setting
- An intervention applied to different populations or groups (defined by demographics or other characteristics)
- Study arms are only considered in Community Guide reviews if they meet the inclusion criteria specific to that review.
Sufficient Evidence of Effectiveness – A body of evidence that provides enough information for the Task Force to determine whether an intervention is effective. The requirements for sufficient evidence are set forth in the translation table.
Suitability of Design – Three possible categories describe suitability: greatest, moderate, or least suitable design. These categories are based on the presence or absence of study design characteristics that affect our confidence that the intervention being evaluated really caused the effects or outcomes being measured (internal validity). Studies with the greatest suitability of design have concurrent comparison groups and prospective measurement of exposures and outcomes. Studies with moderate suitability use retrospective designs or multiple pre or postmeasurements (but not concurrent comparison groups). And studies with least suitability use single pre and post measurements and do not have a concurrent comparison group or measure exposure and outcome in a single group at the same point in time. Read more >> [PDF - 204 kB]
Systematic Review – A process by which a body of literature is reviewed and assessed using systematic methods which are intended to reduce bias in the review process and improve understandability.
Systematic Review Development Team – See Coordination Team
Tailoring – An intervention or program is tailored when it is adapted to address characteristics of individuals. For example, tailoring a health behavior change program means adapting that program to address the individual needs of each participant.(see also Targeting)
Target population – The population or community to which a given intervention is directed.
Targeting – An intervention or program is targeted when it is adapted to address characteristics of groups. For example, point-of-decision prompts (signs placed near elevators that encourage people to take the stairs to increase their physical activity or to lose weight) can be more effective when they address the needs of the people likely to see them.(see also Tailoring)
Team – See Coordination Team
Time Frame – The period during which the intervention or treatment is delivered including any follow-up.
Translation Table – The table [PDF - 36 kB] developed for Community Guide systematic reviews, showing how many studies of what quality are needed to recommend, recommend against, or find insufficient evidence to determine the effectiveness of an intervention.
U.S. Preventive Services Task Force (USPSTF) – A non-federal panel, commissioned by the U.S. Public Health Service in 1984 and 1990, charged with developing recommendations for clinicians on the appropriate use of preventive interventions, based on systematic reviews of evidence of clinical effectiveness. USPSTF findings are presented in the Guide to Clinical Preventive Services (the Clinical Guide).