Table 2 Australian National Health and Medical Research Council Designated Levels of Evidence¹

Evidence obtained from a systematic review of all relevant randomised controlled trials.

Evidence obtained from at least one properly designed randomised controlled trial.

Evidence obtained from well designed pseudo-randomised controlled trials (alternate allocation or some other method).

Evidence obtained from comparative studies with concurrent controls and allocation not randomised (cohort studies), case control studies or interrupted time series with control group.

Evidence obtained from comparative studies with historical control, two or more single arm studies, or interrupted time series without a parallel control group.

Evidence obtained from a case series, either post-test or pre-test and post-test.