Antibodies to thyroglobulin in a titre of 1:25 or more were found in 16·2% of women and 4·3% of men between the ages of 21 and 80 years in a random sample of the population from a general practice in the north-east of England. The incidence of antibodies was highest in the seventh decade in both sexes. High antibody titres (1:78125 or more) were found in 4·6% of women and 1·6% of men and it is suggested that this may represent the incidence of diffuse thyroiditis in the population.
Significant thyroid enlargement was found in 12% of women and 0·9% of men, the corrected incidence of goitre obtained by averaging the frequency of goitres in each decade between 21 and 80 years was 8·9% and 0·9% respectively.