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PRS Efficacy Criteria for Best-Evidence (Tier I) Medication Adherence (MA) Behavioral Interventions

Intervention Description

  • Clear description of key aspects of the intervention

Quality of Study Design

  • Prospective study design
  • Appropriate comparison arm
  • Concurrent comparison arm
  • Random allocation of participants to study arms

Quality of Study Implementation

  • At least a 3-month post-intervention follow-up assessment for each study arm (with recall referring to post-intervention period only) for interventions that are clearly discrete or at least a 6-month post-initiation follow-up assessment for each study arm for all other types of interventions

    At least a 70% retention rate (or medical chart recovery) at a single follow-up assessment for each study arm

Quality of Study analysis

  • Analysis contrasting intervention arm and an appropriate comparison arm
  • Intent-to-treat analysis:
    • Analysis of participants in study arms as originally allocated
    • Analysis of participants regardless of the level of intervention exposure
    • Analysis using appropriate imputations to account for missing data due to attrition or other reasons
  • Use of appropriate cluster-level analyses if allocated to study arms by cluster
  • Comparability of measures:
    • Measures must be identical, including recall, for any repeated measures or change score analyses
    • Baseline measures do not have to be identical, but must be of the same construct as outcome measures, if being used as a covariate in analyses (i.e., adjusted for BL)
  • Analysis based on a 2-sided test and an α =.05 (or more stringent)
  • Analytic sample of at least 50 participants per study arm

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Strength of Evidence–Significant positive intervention effects

  • Positive and statistically significant (p < .05) intervention effect for at least 1 relevant behavioral outcome measure and 1 relevant biologic outcome measure
    • A positive intervention effect is defined as a statistically significant greater improvement in, or better level of, medication adherence behavioral or biologic outcome in the intervention arm relative to the comparison arm.
    • A relevant behavioral outcome measure may include electronic data monitoring (e.g., MEMs caps), pill count, pharmacy refill, or self-reported adherence. A relevant biologic outcome measure may include a lab test or medical chart recovery of HIV viral load levels.
  • Effect at the follow-up and based on the analyses that meet study design, implementation and analysis criteria

Strength of Evidence–Negative intervention effects

  • No negative and statistically significant (p < .05) intervention effect for any HIV-related behavioral or biologic outcome
    • A negative intervention effect is defined as a statistically significant greater improvement in, or better level of, HIV-related behavioral or biologic outcomes in the comparison arm relative to the intervention 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:

  • The totality of the limitations (as described below) cannot introduce considerable bias that substantially reduces the confidence placed on the findings.
  • Examples of limitations to check include:
    • Intervention and comparison arms did not receive similar medication regimens
    • Findings based on too many post-hoc analyses
    • Inconsistent evidence between effects
    • Inconsistent evidence across intervention comparisons within the study
    • Effects only found within a potentially biased subgroup analysis
    • Substantial (>40%) overall missing data (due to attrition and non-attrition such as missing responses)
    • Substantial differential attrition in rates (>10%) or participant characteristics across study arms
    • Differences in characteristics between those lost-to-follow up and those retained in the study
    • Any other notable bias threatening internal or external validity

All criteria must be satisfied for an intervention to be considered as a best-evidence MA intervention.

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