Age at initial capillary sampling in Scottish infants referred with TSH elevation during seven 5-year time periods from 1980 to 2014 (required standard =≤7 days)
| Time period | Referred, n | Median, days | Tested at 4–7 days, n (%) | Tested 8–10 days, n,(%) | Tested >10 days, n (%) | Unknown |
| 1980–1984 | 95 | 7 | 56 (58.9) | 27 (28.4) | 11 (11.5) | 1 |
| 1985–1989 | 147 | 6 | 105 (71.4) | 27 (18.3) | 15 (10.2) | 0 |
| 1990–1994 | 119 | 7 | 83 (69.7) | 24 (20.1) | 10 (8.4) | 2 |
| 1995–1999 | 112 | 6 | 93 (83.0) | 14 (12.5) | 4 (3.5) | 1 |
| 2000–2004 | 150 | 6 | 123 (82.0) | 17 (11.3) | 10 (6.6) | 1 |
| 2005–2009 | 156 | 5 | 144 (92.3) | 7 (4.4) | 3 (1.9) | 2 |
| 2010–2014 | 140 | 5 | 136 (96.4) | 3 (2.1) | 2 (1.4) | 0 |
n, number; TSH, thyroid-stimulating hormone.