Table 2.
Risk of bias of included RCTs
| Cluster-RCTs | |||||||
| Study | Domains | ||||||
| Randomization process | Identification and recruitment of participants | Effect of assignment to intervention | Missing outcome data | Measurement of the outcome | Selection of the reported result | ||
| Akerblad 2003 [26] | High | Low | Low | Low | Some concerns | Low | |
| Chang 2014 [72] | Low | Low | Low | Low | Some concerns | Low | |
| Keeley 2014 [38] | Low | Low | Low | Low | Some concerns | Some concerns | |
| LeBlanc 2015 [41] | Unclear | Low | Some concerns | Low | Some concerns | Low | |
| Pradeep 2014 [52] | Some concerns | Low | Low | Some concerns | Low | Low | |
| Richards 2016 [53] | Low | Low | Low | Low | High | Low | |
| Vergouwen 2009, 2005 [62, 63] | Low | Low | Low | Some concerns | Some concerns | Low | |
| Individually RCTs | |||||||
| Study | Domains | ||||||
| Randomization process | Effect of assignment to intervention | Missing outcome data | Measurement of the outcome | Selection of the reported result | |||
| Adler 2004 [25] | Low | Low | Low | High | Low | ||
| Aljumah & Hassali, 2015 [59] | Low | Some concerns | High | Low | Low | ||
| Al-Saffar 2008, 2005 [37, 48] | Low | Low | Some concerns | Some concerns | Low | ||
| Browne 2002 [70] | Low | Low | Low | Low | Low | ||
| Capoccia 2004 [71] | Some concerns | Low | Low | Some concerns | Low | ||
| De Jonghe 2001 [74] | Low | Some concerns | Low | Some concerns | Some concerns | ||
| Guo 2015 [67] | Some concerns | Low | Low | Some concerns | Some concerns | ||
| Hammonds 2015 [29] | Some concerns | Some concerns | Some concerns | Low | High | ||
| Interian 2013 [30] | Some concerns | Low | Low | Low | Low | ||
| John 2016 [31] | Low | Low | Some concerns | High | Some concerns | ||
| Katon 2002 [32] | Some concerns | Low | Some concerns | Some concerns | Some concerns | ||
| Katon 2001 [33] | Some concerns | Some concerns | Low | Some concerns | Low | ||
| Katon 1999 [34] | Low | Low | Low | Low | Low | ||
| Katon 1996 [35] | Some concerns | Some concerns | Low | Some concerns | Low | ||
| Katon 1995 [36] | Low | Low | Low | Some concerns | Low | ||
| Kutcher 2002 [40] | Low | Some concerns | High | Some concerns | Low | ||
| Perlis 2002 [75] | Some concerns | Low | Low | Some concerns | Low | ||
| Lin 2003 [42] | Some concerns | Low | Low | Low | Low | ||
| Lin 1999 [43] | Some concerns | Low | Some concerns | High | Low | ||
| Mantani 2017 [44] | Low | Low | Low | Some concerns | Low | ||
| Mundt 2001 [46] | Some concerns | Some concerns | Low | Some concerns | Low | ||
| Myers & Calvert, 1984 [49] | Some concerns | Low | Low | Some concerns | Low | ||
| Nwokeji 2012 [50] | High | Low | Low | Some concerns | Low | ||
| Perahia 2008 [51] | Some concerns | Low | Low | High | Low | ||
| Salkovskis 2006 [56] | Some concerns | Low | Some concerns | High | Some concerns | ||
| Rickles 2006, 2005 [54, 55] | Low | Low | High | Low | Low | ||
| Simon 2006 [57] | Low | Low | Low | Low | Low | ||
| Simon 2011 [58] | Low | Low | Low | Some concerns | Low | ||
| Smit 2005 [60] | High | Some concerns | Low | Low | Low | ||
| Vannachavee 2016 [61] | Some concerns | Low | Some concerns | Low | Low | ||
| Wiles 2014, 2013 [65, 66] | Low | Low | Some concerns | Some concerns | Low | ||
| Wiles 2008 [64] | Low | Low | Low | Some concerns | Low | ||
| Marasine, 2020 [69] | Low | Some concerns | Some concerns | Low | Low | ||
| Yusuf, 2021 [68] | Low | Some concerns | Some concerns | Low | Low | ||
High, High risk of bias, Low Low risk of bias, Unclear Unclear risk of bias
RCTs Randomized controlled trials