To make recommendations for screening Canadian newborn infants for congenital hypothyroidism. This updates a 1990 Canadian Task Force report. The incidence of hypothyroidism ranges between 1 in 4,000 to 1 in 3,500 live births and can be as high as 1 in 141 live births among infants with Down Syndrome. Before screening was available, the age at diagnosis ranged from 1 week to 5 years or more. Children whose mothers ingested iodides, propylthiouracil or radioactive iodide or had circulating antithyroid antibodies are at high risk for congenital hypothyroidism.
Treatment includes restoration and maintenance of normal thyroid levels.
Outcomes Sensitivity and positive predictive values of the screening tests and recall rates. Only original articles were included. Recommendations were not based on cost-effectiveness of options. Patient preferences were not discussed. Background papers providing critical appraisal of the evidence and tentative recommendations prepared by the chapter author were pre-circulated to the members.