Table 4.

Risk of bias for non randomized trials

Authors	Confounding bias	Selection of participants bias	Measurement of interventions bias	Departures from intended interventions bias	Missing data bias	Measurements of outcomes bias	Selection of the reported results Bias	overall bias
Hansson and Rindler [27]	Serious	Low	Serious	Low	Moderate	Moderate	Low	Serious
Mummolo et al. [10]	Serious	Low	Moderate	Low	Low	Moderate	Low	Moderate
Bollero et al. [22]	Serious	Serious	Serious	Low	Serious	Moderate	Low	Serious
Caprioglio et al. [23]	Serious	Low	Moderate	Low	Moderate	Moderate	Low	Moderate
Evren et al. [24]	Serious	Moderate	Serious	Low	Serious	Serious	Low	Serious
Zasciurinskiene et al. [25]	Serious	Moderate	Moderate	Low	Low	Low	Low	Moderate
Crescini et al. [26]	Serious	Low	Serious	Low	Low	Serious	Low	Serious
Zafarmand and Gholami [20]	Serious	Serious	Moderate	Low	Moderate	Moderate	Low	Moderate
Szarmach et al. [21]	Serious	Moderate	Moderate	Low	Serious	Serious	Low	Serious