SKEWED DISTRIBUTIONS - NEW OUTCOME MEASURES

The traditional measure of caries, the DMF index, either as prevalence or incidence of disease, has become highly positively skewed among ch ildren and young adults. Most discussion of skewed distributions has f ocused on the properties of statistical analyses using such data or th e implications for sample sizes and subject selection in clinical tria ls. This paper examines the full range of epidemiologic studies, their aims and constitutive interest in order to identify the measurement p roblems associated with skewed DMF index data. Constitutive interests include: description; documentation; explanation and prediction; evalu ation; advocacy; and, experimentation. 'New' outcome measures that wou ld assist in reaching the aims and constitutive interests of the epide miology of caries include caries severity grading, variants of prevale nce, extent and severity and their combination into case definitions. and weighting of the components of the DMF index. Research questions f or each area of 'new' outcome measures are identified as steps in the codifying of their use in the epidemiology of caries.