Strong evidence: multiple RCTs of high quality with consistent
positive results;To determine the level of evidence for a given outcome
measure, two independent reviewers (ES, MP) scored
whether the outcome was either positive (a significant difference
(p0.05) in favor of the intervention on a relevant
outcome measure) or negative (a nonsignificant difference
or a significant difference in favor of the control condition).
In case of disagreement, consensus was reached by discussion.
Overall results were considered consistent if at least 75% of
the studies involved reported positive results.