Table 4 Risk of bias assessments for each criterion using the NHLBI tool for case series studies

Study

Was the study question clearly stated?

Was the study population clearly described?

Were the cases consecutive?

Were the subjects comparable?

Was the intervention clearly described?

Were the outcomes clearly defined, valid, reliable, and applied consistently?

Was the length of the follow-up adequate?

Were the statistical methods well described?

Were the results well described?

Quality of Study