Table 1.
characteristics of the included studies
| Author, year | Type of study | ultrasonography device |
Population
of study |
Total population | Male percent | Operator | Cut-off for US grading | Reference standard test | Age of ultrasonography |
| Rosendahl, 1996 (16) | Cohort | NA | Universal screening | 51 | Radiologist | IIb | Clinical follow up for 3 years | 1-3 days | |
| Roovers, 2005 (18) | Retrospective cohort | Hitachi (EUB-405) with a linear transducer (7.5 or 5 MHz) |
Universal screening | 5170 | NA | Radiologist technician | IIb | Follow up US in 8 months | First three months of life |
| Pillai, 2011 (15) | Cohort | Acuson™ linear 7 MHz probe | Selective screening | 249 | 34.3 | Orthopedic consultant | III | AP pelvic radiograph at 6 months | 29-77 days |
| Kumar, 2016 (19) | Retrospective cohort | NA | Selective screening | 662 | NA | Radiologist | IIa | At least 2-year follow up | 6 weeks |
| Gokharman, 2019 (14) | Cohort | Toshiba Xario, 7.5-MHz linear transducer, and Toshiba Aplio 300, 10-MHz linear transducer |
Selective screening | 360 (4 weeks), 819 (8 weeks) | 47 | Radiologist | IIc | US follow up at 12 weeks | 4 and 8 weeks |
| Tan, 2020 (17) | Retrospective cohort | NA | Selective screening | 160 | NA | Radiologist | IIb | Pelvis radiograph at 1 year | <12 weeks |