Quality assessment of included studies using the Newcastle-Ottawa Scale

StudySelection (0–4)Comparability (0–2)Outcome (0–3)Total Score (0–9)Quality rating
Duggan et al. [17] (2014)4239High
Fordyce et al. [18] (2006)4228High
Gay-Bellile et al. [19] (2016)4239High
Heaphy et al. [20] (2007)4239High
Lu et al. [21] (2011)4239High
Shen et al. [23] (2012)4239High
Simpson et al. [22] (2015)4239High
Svenson et al. [24] (2008)4228High
Vodenkova et al. [25] (2020)4228High