Eligible studies and patient demographics
| Author (yr) | Case Ears/Control Ears (n) | Bilateral Cases Included Y/N (n) | Age (Cases) | Sex (Cases) | Age (Controls) | Sex (Controls) |
|---|---|---|---|---|---|---|
| Bae et al (2017)7 | 16/14 | Y (1 bilateral) | 54.1 (27–84) | 5 m/10 f | NA | NA |
| Best et al (2013)8 | 40/40 | NA | 47.2 (SD, 14.7) (17–78) | 8 m/12 f | 48.4 (SD, 14.9) (25–77) | 8 m/12 f |
| Beyazal Celiker et al (2017)9 | 356/478 | NA | 50.1 (SD, 17.3) | 63 m/115 f | 42.1 (SD, 18.9) | 119 m/120 f |
| Ezerarslan et al (2017)10 | 68/76 | N | 45.3 (SD, 14.6) (18–77) | 36 m/32 f | 48.6 (SD, 14.0) (26–81) | 21 m/17 f |
| Gorrie et al (2010)11 | 58/56 | N | NR | 31 m/27 f | NA | NA |
| Gultekin et al (2008)12 | 68/128 | Y (13 bilateral) | 48.5 (18–78) | 23 m/32 f | 42.2 (19–88) | 9 m/34 f |
| Kierig et al (2023)1 | 36/36 | NA | 52.6 (SD, 18.1) (28–84) | 12 m/6 f | 50.3 (SD, 16.5) | 5 m/13 f |
| Kim et al (2019)13 | 49/49 | N | 45.0 (SD, 15.3) | 58 m/40 f | NA | NA |
| Leng et al (2022)14 | 136/136 | N | 43 (SD, 13) | 60 m/76 f | NA | NA |
| Maruyama et al (2020)15 | 248/392 | N | 51.1 (SD, 17.2) (8–84) | 121 m/127 f | 55.2 (SD, 16.8) (10–84) | 77 m/67 f |
| Ozan and Arslan (2017)16 | 92/85 | N | 53.6 (SD, 14.2) (20–84) | 42 m/50 f | 52.2 (SD, 15) (23–79) | 39 m/46 f |
| Peters et al (2020)17 | 48/49 | N | 52 (23–76) | 24 m/25 f | NA | NA |
| Sivarasan et al (2019)18 | 9/20 | N | 48.4 (SD, 14.0) | 5 m/4 f | NA | NA |
| Yoo et al (2011)19 | 85/173 | Y (29 bilateral) | 47.3 (SD, 12.7) | 30 m/44 f | NA | NA |
| Zhang et al (2023)20 | 77/77 | N | 47.6 (SD, 14.3) | 45 m/34 f | NA | NA |
| Zidan and Almansor (2020)21 | 140/120 | N | 47.6 (SD, 15) (11–73) | 47 m/51 f | 45.6 (SD, 11.7) (19–88) | 28 m/32 f |
Note:—n indicates number of patients; Y, yes; N, no; NA, not available; NR, not recorded; m, male; f, female.