Table 5. Risk of bias assessment of the included studies, using the ROBINS-I tool.

ROBINS-I = Risk Of Bias in Non-Randomised Studies Tool

Authors	Study Design	Confounding	Selection participant	Classification of intervention	Missing data	Outcome measurement	Selection of reported result	Overall risk of bias
Abadal Centellas et al., 2007 [29]	Retrospective	Moderate	Moderate	Moderate	Low	Low	Low	Moderate
Bauer et al., 2017 [31]	Retrospective	Moderate	Moderate	Moderate	Low	Low	Moderate	Moderate
Levy et al., 1995 [32]	Retrospective	Moderate	Low	Moderate	Moderate	Low	Low	Moderate
Llompart Pou et al., 2011 [33]	Retrospective	Moderate	Moderate	Low	Moderate	Moderate	Low	Moderate
Manet et al., 2016 [34]	Retrospective	Moderate	Moderate	Low	Low	Low	Low	Moderate
Manet et al., 2017 [35]	Retrospective	Moderate	Low	Low	Moderate	Moderate	Low	Moderate
Murad et al., 2012 [25]	Prospective	Moderate	Low	Moderate	Low	Low	Low	Moderate
Tuettenberg et al., 2009 [23]	Prospective	Moderate	Moderate	Moderate	Moderate	Low	Low	Moderate
Willemse, 1998 [37]	Retrospective	Moderate	Moderate	Moderate	Moderate	Low	Low	Moderate