Randomised controlled trials not included in any systematic review, with reasons.

<p>Randomised controlled trials not included in any systematic review, with reasons.</p

Systematic review characteristics and quality, with number of included and non-included RCTs.

<p>Systematic review characteristics and quality, with number of included and non-included RCTs.</p

Currency, completeness, and quality of single-intervention systematic reviews.

<p>Each bubble represents a single-intervention systematic review (n = 80). The ideal scenario is for bubbles to sit in the bottom right corner (denoting high quality and completeness), and be green in colour (denoting currency). Abbreviations: RCT = randomised controlled trial, SR = systematic review.</p