Accuracy of NicAlert^TM Strips Tested with Urine and Saliva

OBJECTIVE: The COHRA (Center for Oral Health Research in Appalachia) study of dental health disparities in Appalachia ascertains smoking status by parental and self-report, which is confirmed by testing saliva with Accutest^® NicAlert^TM strips (Jant Pharmaceutical Corporation). Because of occasional discrepancies between self-report and NicAlert^TM data, we checked the accuracy of the NicAlert^TM strips using saliva and urine from the same individuals.

METHODS: We collected anonymous demographic data, including smoking and tobacco-chewing status and history, as well as exposure to second-hand smoke, from 59 adults aged 21 to 67. Urine and saliva samples were tested using NicAlert^TM strips following manufacturer's specifications.

RESULTS: 20 self-reported smokers (S), 20 non-smokers (NS), 14 non-smokers exposed to second-hand smoke (SHS), and 5 tobacco chewers (T) completed the protocol. NicAlert^TM strips using urine confirmed smoking status in 17/20 S, 18/20 NS, all 14 SHS, and 4/5 T. NicAlert^TM strips using saliva confirmed smoking status in 18/20 S, 17/20 NS, 12/14 SHS, and 4/5 T. Five subjects were misclassified by both urine and saliva tests, including two light daily smokers who smoked more in the evening, two non-smokers who had quit smoking within weeks of the study (one was still chewing Nicaret gum), and one chewer who consumed ½ to 1 tin per week. Three additional subjects were misclassified only by the saliva test, and one was misclassified only by the urine test. Assuming that the self-report data are correct in this sample of adults with no incentive to lie, the NicAlert^TM results were accurate in 53/59 (90%) subjects using urine, and in 51/59 (86%) using saliva.

CONCLUSIONS: When they conflict with a subject's self-reported smoking status, NicAlert^TM results should not be considered completely accurate in all circumstances. Urine was slightly more accurate than saliva, but not enough to be recommended over saliva.

Supported by NIH grant #R01-DE014889