Table 3 — Methodologic Rigor (articles classified according to the purpose categories shown in Table 2 were evaluated for methodologic rigor, except for cost and qualitative studies, and studies classified as something else)
Purpose Category |
Definition |
Causation (Etiology)
|
Observations concerned with the relationship between exposures and putative clinical outcomes;Data collection is prospective;Clearly identified comparison group(s);Blinding of observers of outcome to exposure. |
Prognosis
|
Inception cohort of individuals all initially free of the outcome of interest;Follow-up of ³80% of patients until the occurrence of a major study end point or to the end of the study; Analysis consistent with study design. |
Diagnosis
|
Inclusion of a spectrum of participants;Objective diagnostic (“gold”) standard OR current clinical standard for diagnosis;Participants received both the new test and some form of the diagnostic standard;Interpretation of diagnostic standard without knowledge of test result and vice versa;Analysis consistent with study design. |
Therapy
|
Random allocation of participants to comparison groups;Outcome assessment of at least 80% of those entering the investigation accounted for in 1 major analysis at any given follow up assessment;Analysis consistent with study design. |
Economics
|
Question is a comparison of alternatives;Alternative services or activities compared on outcomes produced (effectiveness) and resources consumed (costs);Evidence of effectiveness must be from a study of real patients that meets the above-noted criteria for diagnosis, treatment, quality improvement, or a systematic review article; Effectiveness and cost estimates based on individual patient data (micro-economics); Results presented in terms of the incremental or additional costs and outcomes of one intervention over another;Sensitivity analysis if there is uncertainty. |
Clinical Prediction Guides
|
Guide is generated in one or more sets of real patients (training set); Guide is validated in another set of real patients (test set). |
Reviews
|
Statement of the clinical topic; Explicit statement of the inclusion and exclusion criteria;Description of the methods;³ 1 article must meet the above noted criteria. |