History and Objectives: Considering the importance of correctness of laboratory results in correct and prompt diagnosis of disorders and the existence of different methods and the existence of concerns among patients and physicians, this study was conducted on to evaluate the correctness of the results of biochemical, serological and endocrine tests in Kashan laboratories from 1998 to 1999.

Materials and Methods: The descriptive strategy of this study was carried out on all of the Kashan laboratories. For this purpose, standard solutions for glucose, BUN, creatinine, uric acid, cholesterol and triglyceride were purchased from Biometrix company and serum samples were collected from patients with thyroid disorders and for serological tests, Right’s positive sample was collected. Then samples were transferred to the laboratories in similar conditions.

Results: This study was conducted on 3842 tests from 12 laboratories and 82% out of them participated in the study. The correctness for hormonal, serological and biochemical was 90.3%, 55% and 55%, respectively. The most precise results were those from T4 test (96.5%), Right’s test (77.8%) and BUN (61.58%). In addition, the most precise results were those from L and H laboratories and the least precise result was that from B laboratory.

Conclusion and Recommendations: The correctness of laboratory results was low and it is recommended to carry out more experimental studies in this respect.