A comparison of treatment effectiveness between clear aligner and fixed appliance therapies

Table 3 Quality assessment of included cohort studies

Reference	Selection				Comparability	Outcome			Total score
Reference	Representativeness of the exposed cohort	Selection of the non-exposed cohort	Ascertainment of exposure	Demonstration that outcome of interest was not present at start of study	Comparability of cohorts on the basis of the design or analysis	Assessment of outcome	Was follow-up long enough for outcomes to occur	Adequacy of follow up of cohorts	Total score
Djeu2005	*	*	*	*	*	*	*	*	8
Kuncio2007	*	*	*	*	**	*	*		8
Pavoni2011		*	*	*		*	*	*	6
Grunheid2016		*	*	*	**	*	*	*	8
Gu2017	*	*	*	*	*	*	*	*	8
Lanteri2018		*	*	*	**	*	*	*	8