Thyroid diseases can occur at different ages, and the type of disorder is somewhat age and sex related. Measuring the level of free hormones is the most reliable diagnosis method since the concentrations of fT3 and fT4 are independent of the carrier protein concentration. The aim of this paper is to determine the number of positive findings in relation to the number of referrals and to consider the ways and methods for possible rationalization of referrals. This research was carried out by a retrospective observation method in the emergency biochemical laboratory of the General County Hospital Vinkovci. The population investigated are patients who were first referred to the laboratory with the diagnosis of thyroid disease, apart from malignant diseases, over the course of several months 2016. The number of patients from January 2016 to June 2016 was 1128. There were 306 male (27.13 %) and 822 female patients (72.87 %). The smallest number of referrals is for patients under 20 years of age, with the lowest number of positive findings (14.63 %), and the highest number of positive findings (21.30 %) is in the group 40-60 years of age. The study was conducted for 5 groups of diseases: latent hypothyroidism, non-thyroid disease, hypothyroidism, hyperthyroidism and other diseases associated with thyroid disorders. Latent hypothyroidism is the most prevalent disease and most often includes an age group over 50 years (38.80 %) of all illnesses. There is disproportionately large number of referrals in comparison to the number of positive findings. The implementation of indicative target area for thyroid disease and better education of medical experts are necessary to lower the number of referrals. Analysing and monitoring of the findings in the laboratory through the data registers could become routine procedures with the implementation of software for analysis and graphical presentation of the results of the findings, which would improve the quality of the laboratory work and serve as a basis for continuous improvement of work and better recognition of clinical syndromes.