A NATIONAL EPIDEMIOLOGIC SURVEY OF ORAL MUCOSAL LESIONS IN MALAYSIA

The prevalence of oral mucosal lesions in Malaysia was determined by e xamining a representative sample of 11 707 subjects aged 25 years and above throughout the 14 states over a period of 5 months during 1993/1 994. A two-stage stratified random sampling was undertaken, A predeter mined number of enumeration blocks, the smallest population unit in th e census publication, was selected from each state. With the selected enumeration block, a systematic sample of living quarters was chosen w ith a random start. The survey instrument included a questionnaire on sociodemographic characteristics and a clinical examination. The clini cal examination was carried out by 16 specially trained dental public health officers and the diagnosis calibrated with a final concordance rate of 92%. The age in the sample ranged from 25 to 115 years with a mean of 44.5+/-14.0. The sample comprised 40.2% males and 59.8% female s; 55.8% were Malays, 29.4% Chinese, 10.0% Indians and 1.2% other ethn ic groups. Oral mucosal lesions were detected in 1131 (9.7%) subjects, 5 (0.04%) had oral cancer, 165 (1.4%) had lesions or conditions that may be precancerous (leukoplakia, erythroplakia, submucous fibrosis an d lichen planus) and 187 (1.6%) had betel chewer's mucosa. The prevale nce of oral precancer was highest amongst Indians (4.0%) and other Bum iputras (the indigenous people of Sabah and Sarawak) (2.5%) while the lowest prevalence was amongst the Chinese (0.5%).