. 2020 Sep 28;2020:4753645. doi: 10.1155/2020/4753645

Table 4.

Newcastle-Ottawa Quality Assessment Scale: cohort studies.

Study ID	Selection				Comparability^e		Exposure			Total scores
	Representativeness^a	Selection^b	Ascertainment^c	Demonstration^d	Important factor^f	Additional factor^g	Assessment^h	Follow-up
	Representativeness^a	Selection^b	Ascertainment^c	Demonstration^d	Important factor^f	Additional factor^g	Assessment^h	Lengthⁱ	Adequacy^j
Sun 2019	Representative^★	Same source^★	Secure record^★	Yes^★	Yes^★	Yes^★	Record linkage^★	Yes^★	No description	8^★

a: representativeness of the exposed cohort; b: selection of the nonexposed cohort; c: ascertainment of exposure; d: demonstration that outcome of interest was not present at the start of study; e: comparability of cohorts on the basis of the design or analysis; f: study controls for selecting the most important factor; g: study controls for any additional factor; h: assessment of outcome; i: was follow-up long enough for outcomes to occur; j: adequacy of follow-up of cohorts. ★: earns a star.