Numbers of adequately powered studies (≥50% power) and median power within each meta-analysis (MA) with respect to a 30% relative risk reduction (RRR30), overall and by medical specialty, outcome type and intervention-comparison type.

1Other medical specialties: Blood and immune system, Ear and nose, Eye, General health, Genetic disorders, Injuries, accidents and wounds, Mouth and dental, Skin.2Other semi-objective outcomes: External structure, Internal structure, Surgical/device related success/failure, Withdrawals/drop-outs.3Other subjective outcomes: Pain, Mental health outcomes, Quality of life/functioning, Consumption, Satisfaction with care, Composite (at least 1 non-mortality/morbidity).4Non-pharmacological interventions include interventions classified as medical devices, surgical, complex, resources and infrastructure, behavioural, psychological, physical, complementary, educational, radiotherapy, vaccines, cellular and gene, screening.