TABLE 2

Study quality assessment using modified QUADAS-2a

StudyRisk of selection biasRisk of nongeneralizabilityRisk of flow bias
Avidor et al. (21)UnclearUnclearLow
Bruzzone et al. (19)UnclearLowLow
Ceffa et al. (11)LowLowLow
Garrett et al. (14)LowLowLow
Gous et al. (12)UnclearUnclearUnclear
Gous et al. (12)UnclearLowUnclear
Gueudin et al. (15)UnclearLowLow
Jordan et al. (16)LowLowHigh
Kulkarni et al. (22)UnclearUnclearLow
Mor et al. (17)UnclearUnclearLow
Moyo et al. (18)UnclearUnclearUnclear
Nash et al. (20)LowLowLow
Swathirajan et al. (23)UnclearUnclearLow
• a Risk of biases assessed using modified QUADAS-2 (10). Unclear risk denotes there was insufficient information provided in the paper to assess the particular bias.