Screening for thyroid disorders in middle-aged women by computer-assisted evaluation of a thyroid hormone panel

Free thyroxine index, free tri-iodothyronine index and thyrotropin were determined in connection with gynecological screening for cervical carcinoma on middle-age women. A total of 3885 women were investigated. Women with values outside a trivariate reference region were reinvestigated by renewed hormone determinations and those with hormone results still outside the reference region were subjected to clinical and further laboratory investigations. Thus 20 women (0.51% of the study population) with previously unknown hyperthyroidism and 25 women (0.64%) with previously unknown hypothyroidism were identified and successfully treated. Values outside the reference region were also studied by cluster analysis, which separated hyper- and hypo thyroid patients into different clusters. but allowed no further identification of different thyroid disorders. We conclude that laboratory screening for thyroid disorders may be justified in middle aged women if performed together with another screening program. Computer-assisted multivariate evaluation of the hormone results was of value of identification of subjects with thyroid disorders but their numerical classification by cluster analysis was of little practical value.