The initial screening test was positive for 322 of the men (28.8 percent of the sample), half of whom were confirmed to have consumed opiates by thin-layer chromatography (TLC), which identified the opiates with a high degree of specificity. Thus, 14.4 percent of the urine samples were determined to be positive for opioid metabolites. Although this sample was not precisely representative of the general population, the author suggests revising the urine test as the sole screening and detection method for identifying Iranians who use opiates for nonmedical reasons. Urine samples were obtained from men referred by physicians for urinalysis as a checkup test. The men averaged 46.6 years old. All stages of the study were performed by anonymous unlinked testing. Urine sample analysis was done at the Neuroscience Research Center at Kerman University of Medical Sciences in two stages: rapid situation assessment method, an immunoassay method capable of recognizing up to 300 ng/ml of opiates in urine; and TLC, which is capable of identifying opiates in urine with a high degree of specificity. 1 figure and 23 references