. 2021 Jan 8;9(1):100294. doi: 10.1016/j.esxm.2020.100294

Table 1.

Summary characteristics and risk of bias (Murad et al tool) for all included studies

Authors	Year	Technique	Sample type	Dates of study	Sample age	Follow-up time (in months)	Risk of individual bias
Vukadinovic et al.²⁰	2014	Belgrade	Prospective cohort	March 2008–January 2013	29 (18–41)	30	Low; study represents the whole experience of the center during the study period, has adequate follow-up time, clearly describes outcomes, and provides sufficient details about outcomes of interest.
Djordjevic et al.¹⁹	2009	Belgrade	Retrospective cohort	September 2002–April 2007	31 (18–54)	32 (14–69)	Low; study represents the whole experience of the center during the study period, has adequate follow-up time, clearly describes outcomes, and provides sufficient details about outcomes of interest.
Perovic and Djordjevic¹⁸	2003	Belgrade	Retrospective cohort	September 1995–April 2002	26.2 (18–33)	47 (6–72)	Moderate; study represents the whole experience of the center during the study period, has adequate follow-up time, describes the outcomes of interest but does not provide sufficient detail about management nor severity of complications.
Stojanovic et al.²¹	2017	Belgrade	Retrospective cohort	January 2007–March 2016	31.5 (18–43)	44 (10–92)	Low; study represents the whole experience of the center during the study period, has adequate follow-up time, clearly describes outcomes, and provides sufficient details about outcomes of interest.
Takamatsu and Harashina¹²	2009	Labial ring flap	Retrospective cohort–	2005–2007	18–33	7 (3–96)	Moderate; study represents the whole experience of the center during the study period, clearly describes outcomes and provides sufficient details about the outcomes of interest but does not have a sufficient follow-up time to adequately assess for complications
Cohanzad²²	2016	Extensive	Retrospective cohort–	2007–2014	28 (20–40)	68 ± 15	High; while the follow-up period is adequate, the study has a small sample and only reports on outcomes for a small subsect of the already small sample with a poor description of outcomes
Hage and Van Turnhout¹⁷	2006	Hage	Retrospective cohort	December 1991–March 1999	30 (19–53)	96 (54–132)	Low; study represents the whole experience of the center during the study period, has adequate follow-up time, clearly describes outcomes, and provides sufficient details about outcomes of interest.