Audit of investigation of subclinical hypothyroidism in Scottish laboratories

Background An audit of thyroid function testing in the investigation of subclinical hypothyroidism in Scotland was performed. Methods The audit looked at the tests used and the strategies employed by 18 out of a total of 25 Scottish laboratories and found significant differences between them. It also looked at the comments and advice given by 59 clinical scientists and chemical pathologists in the interpretation of results from patients with subclinical hypothyroidism. These comments were compared with standards derived from guidelines in current literature. Results The advice given was generally accurate and helpful but the audit showed a marked variation in interpretative comments. Conclusions This variation may reflect the lack of emphasis that has been placed on standardizing the interpretive function of laboratories and underlines the need for liaison both within and between laboratories to achieve better agreement on the interpretation of laboratory tests. The audit also showed that the importance of thyroid peroxidase antibody estimation in subclinical hypothyroidism needs to be emphasized.