Table 2

Newcastle-Ottawa assessment scale of cohort studies within the top 25 most-cited articles ordered by citation ranking.

StudyRepresentative of CohortsSelection of Nonexposed CohortAscertainment of ExposureOutcome of Interest Absent at Start of StudyCohort ComparabilityOutcome AssessmentSufficient Follow-upAdequacy of Follow-upTotal Score
1. Kantelhardt et al (2011)10 ********8
3. Hyun et al (2017)12 *********9
4. Schatlo et al (2014)13 *********9
5. Kim et al (2017)14 *********9
8. Lonjon et al (2016)4 ***** ****9
10. Lieberman et al (2012)18 --*--***4
15. Kim et al (2015)22 ****-***7
18. Le et al (2018)6 --******6
19. Urakov et al (2017)25 --------0
21. Schröder et al (2017)27 --------0
22. Fan et al (2017)28 ****-***7