Figure 1.

Patient population and outcome. Of 1.36 million newborns screened, 867 were diagnosed with congenital hypothyroidism (CH) and started on treatment. Overall, 499 met inclusion criteria; 30 were classified as indeterminate, leaving 469 (94%) of eligible individuals included for analysis. At age 3 years, 360 of the 469 (76.8%) met the criteria for permanent CH and 109 (23.2%) were successfully trialed off levothyroxine and diagnosed with transient CH. Dysgenesis, ectopic thyroid or athyreosis on imaging; GIS, gland in situ on imaging; indeterminate CH, inconclusive or no trial off therapy at age 3 years.