Fig. 1

Systematic review flow chart comparing screening results between a title-only (Ti/O) to a title-plus-abstract (Ti + Ab) screening approach at the first level. 1st level: first-level screening where two investigators independently followed a Ti + Ab screening approach, and a 3rd investigator followed a Ti/O screening approach. 2nd level: second-level screening where the full team rescreened all studies which passed the first-level screen using a Ti + Ab screening approach. Full-text level: full-text screening where the full team screened all studies which passed the second-level screen

¹Population; ²Intervention; ³Comparison; ⁴Outcome; ⁵Study design