| Study Design | Criteria |
|---|---|
| Systematic reviews | Comprehensiveness of sources and search strategy used Standard appraisal of included studies Validity of conclusions Recency and relevance |
| Case-control studies | Accurate ascertainment of cases Nonbiased selection of cases and controls with exclusion criteria applied equally to both Response rate Diagnostic testing procedures applied equally to each group Appropriate attention to potential confounding variables |
| Randomized controlled trials (RCTs) and cohort studies | Initial assembly of comparable groups: - For RCTs: adequate randomization, including concealment and whether potential confounders were distributed equally among groups - For cohort studies: consideration of potential confounders with either restriction or measurement for adjustment in the analysis; consideration of inception cohorts Maintenance of comparable groups (includes attrition, crossovers, adherence, contamination) Important differential loss to followup or overall high loss to followup Measurements: equal, reliable, and valid (includes masking of outcome assessment) Clear definition of interventions All important outcomes considered Analysis: adjustment for potential confounders for cohort studies, or intention-to-treat analysis for RCTs |
| Diagnostic accuracy studies | Screening test relevant, available for primary care, adequately described Study uses a credible reference standard, performed regardless of test results Reference standard interpreted independently of screening test Handles indeterminate results in a reasonable manner Spectrum of patients included in study Sample size Administration of reliable screening test |
|
a Based on reference 27. | |