Table 1. Participant characteristics at baseline.
| Total sample | Birth-registered sex | |||
|---|---|---|---|---|
| n = 44 | male | female | ||
| n = 25 | n = 19 | |||
| Age at consent (years) | Median (IQR) | 13.6 (12.8, 14.6) | 13.4 (12.7, 14.1) | 13.9 (13.5, 14.7) |
| Ethnic group n (%) | white | 39 (89) | 24 (96) | 15 (79) |
| South Asian | 1 (2) | 1 (4) | 0 | |
| black | 2 (5) | 0 | 2 (11) | |
| Mixed ethnicity | 2 (5) | 0 | 2 (11) | |
| Pubertal status n (%) | Stage 2 | 0 | 0 | 0 |
| Stage 3 | 19 (43) | 17 (68) | 2 (10) | |
| Stage 4 | 16 (36) | 5 (20) | 11 (58) | |
| Stage 5 | 9 (21) | 3 (12) | 6 (32) | |
| Menarcheal status n (%) | Premenarcheal | - | - | 4 (21) |
| Post-menarcheal | - | - | 15 (79) | |
| Time in study (months) | Median (IQR) | 31 (20, 42) | 37 (24, 43) | 29 (17, 36) |
| Age at end of pathway (years) | Median (IQR) | 16.1 (16.0, 16.4) | 16.1 (16.0, 16.5) | 16.1 (16.0, 16.3) |
At baseline, all participants had normal endocrinology, karyotype, imaging and clinical phenotype on physical examination for birth-registered sex and normal full blood count and liver and renal function. No participants had evidence of disorders of sexual differentiation. Eight participants (18%) had vitamin D insufficiency at baseline and were given vitamin D supplements.