REPRODUCIBILITY AND VALIDITY OF ORAL VISUAL INSPECTION BY TRAINED HEALTH-WORKERS IN THE DETECTION OF ORAL PRECANCER AND CANCER

A randomized intervention trial is in progress in Kerala, India, to ev aluate the effectiveness of oral visual inspection by trained health w orkers (HWs) in the prevention of oral cancer. Fourteen health workers with college graduation as the basic qualification were trained in or al visual inspection to identify oral cancers and precancers among the participants of the screening trial and to refer them for further con firmation and management. The aim of the present study was to evaluate the reproducibility and validity of the screening test provided by th e health worker against the reference oral visual findings of three ph ysicians. A total of 2069 subjects who had already been examined were re-examined by the health workers and physicians. The sensitivity and the specificity of the oral visual inspection were 94.3% and 99.3% res pectively. There was moderate agreement between the findings of the in itial and the repeat mouth examinations carried out by the health work ers, which were on average 6 months apart. There was almost perfect ag reement (kappa = 0.85) between the findings of the health workers and the physicians in identifying the different types of oral precancerous lesions. The findings of our study indicate that it is possible to tr ain resource persons to perform the oral cancer screening test as accu rately as doctors, although experience appears to be a crucial compone nt of health workers' accuracy. The efficacy of such an approach to re duce the incidence of and mortality from oral cancer, however, remains to be proven.