2009 年 30 巻 2 号 p. 93-104
The validity of the diagnostic criteria for Metabolic Syndrome (MS) has been questioned since the syndrome was introduced. To verify their validity, the best strategy would be a cohort study. However, waist circumference (WC), which is necessary for the diagnosis of MS, was introduced to health examinations only recently. If a current regression model of WC could be transported to a previous sample, a cohort study using estimates of WC would be possible. We propose a sufficient condition for the transportability from a mathematical point of view. Using data from the Radiation Effect Research Foundation, we examined whether the proposed condition may be statistically confirmed in a real dataset. The regression model for weight, which is strongly associated with WC, was used to verify the validity of the condition. The relative risk of death from MS-related causes was obtained. The results indicated that the risk was lower with a greater WC.