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| PRS Efficacy Criteria for Best-Evidence (Tier I) Community-level Interventions (CLIs) |
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Intervention Description
- Clear description of key aspects of the intervention
Quality–Study design
- Prospective study design
- Appropriate and concurrent control/comparison arm
- ≥ 4 communities per arm or appropriate power analysis indicating that a smaller number of communities was adequate (i.e., 2 or 3 communities per arm)
- Select similar communities (units) for assignment
- To minimize selection bias before assignment regardless of assignment methods (randomization or not); use methods such as systematic, a-priori approaches to choose intervention and control communities that are similar (e.g., matching or stratification on factors related to important/appropriate community characteristics)
Quality–Study implementation and analysis
- Sample individuals from assigned communities in acceptable ways (e.g., random, systematic) and use identical methods and eligibility criteria for selecting participants in each community, study arm, and data collection wave
- If demographic differences are identified a priori, differential selection (e.g., over-sampling based on demographics) may be used to achieve equivalence between study arms on those factors
- Follow-up assessment ≥ 3 months post completion of entire time-specific CLI or post full implementation of on-going CLI with recall
not referring to pre-intervention period
- “Post full implementation of an on-going CLI” means after all components of the CLI have been started or put in place in communities
- If cohort, at least 70% retention rate at a single follow-up assessment for each study arm
- If cohort chart review, ≥ 70% success rate in matching medical records
- Comparison between intervention arm and an appropriate comparison arm
- Analysis of communities (units) and analysis of individuals within the communities as originally assigned regardless of contamination or logistic/implementation issues
- Analysis of communities (units) regardless of community level of intervention exposure
- Analysis of individuals within the communities (units) regardless of individual level of intervention exposure
- Use of appropriate cluster-level analyses, e.g., adjusting for ICC
- Analysis must be based on postintervention levels or among pre-post changes in measures
- For pre-post changes used in analysis, measures must be identical, including identical recall period
- Analysis based on an a=.05 (or more stringent) and a 2-sided test
- Either no statistical differences in baseline levels of the outcome exist or baseline differences are controlled for in the analysis, regardless of allocation method (e.g., randomization, non-randomization)
- No differences on baseline levels of the outcome means reporting no significant difference between groups on BL relevant outcomes or match/stratify/statistically adjust participant data by using propensity scores or relevant outcome covariates (regardless of assignment methods - RCT or non-RCT)
Strength of Evidence–Significant positive intervention effects
- Positive and statistically significant (p ≤ .05) intervention effect for ≥ 1 relevant outcome measure
- A positive intervention effect is defined as a greater reduction in HIV/STD incidence or risk behaviors or a greater increase in HIV protective behaviors in the intervention arm relative to the comparison arm.
- A relevant outcome is defined as a behavior (e.g., abstinence, mutual monogamy, number of sex partners, negotiating safer sex, condom use, injection drug use) that directly impacts HIV risk or a biologic measure indicating HIV or STD infection (i.e., HIV or STD incidence)
- Effect at the follow-up and based on the analyses that meet study implementation and analysis criteria
Strength of Evidence–Negative intervention effects
- No negative and statistically significant (p < .05) intervention effect for any relevant outcome
- A negative intervention effect is defined as a greater increase in HIV/STD incidence or risk behaviors or a greater decrease in HIV protective behaviors in the intervention arm relative to the comparison arm.
- No other statistically significant harmful intervention effect
- For an intervention with a replication evaluation, no significant negative intervention effects in the replication study
Additional Limitations to Evaluate:
- No evidence that additional limitations resulted in a fatal flaw:
- A fatal flaw has occurred when the overall evaluation of limitations resulted in considerable bias, thus substantially reducing the confidence of the findings
- Examples of limitations to check for possible fatal flaw:
- Group non-equivalence in baseline measures of important demographics or risk factors
- Differential Retention (for cohort studies): (1) association between study arms and characteristics related to retention or attrition; OR (2) more than minimal rate of differential retention (> 10%)
- Differential Refusal: At baseline for cohort studies; by wave for
serial cross-sectional studies: (1) association between study arms and characteristics related to refusal; OR (2) more than minimal rate of differential refusal rate (> 100)
- Intervention activities did not match with the intervention concepts or guiding theories intended to produce the desired outcomes
- Did not clearly describe issues related to generalizability
- Effects only found within a potentially biased subset analyses
- Substantial missing data (> 10% or missing data plus loss to attrition does not exceed acceptable limits for retention alone)
- Too many post hoc analyses (even with Bonferrroni corrections)
- Pilot study or very small sample size per study arm (< 50)
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