The physical examination content of the Japanese National Health and Nutrition Survey: temporal changes.

Background: Survey items of the Japan National Nutrition Survey (J-NNS) have changed over time. Several papers on dietary surveys have been published; however, to date, there are no in-depth papers regarding physical examinations. Therefore, we investigated changes in the survey items in the physical examinations performed in the J-NNS and the National Health and Nutrition Survey (NHNS), with the aim of incorporating useful data for future policy decisions. Methods: We summarized the description of physical examinations and marshaled the changes of survey items from the J-NNS and NHNS from 1946 to 2012. The physical examination is roughly classified into the following six components: some are relevant to anthropometric measurements, clinical measurements, physical symptoms, blood tests, lifestyle and medication by interview, and others. Results: Items related to nutritional deficiency, such as anemia and tendon reflex disappearance, and body weight measurements were collected during the early period, according to the instructions of the General Headquarters. From 1989, blood tests and measurement of physical activity were added, and serum total protein, total cholesterol, triglycerides, HDL-cholesterol, blood glucose, red blood corpuscles and hemoglobin measurements have been performed continuously for more than 20 years. Discussion: This is the first report on the items of physical examination in the J-NNS and NHNS. Our research results provide basic information for the utilization of the J-NNS and NHNS, to researchers, clinicians or policy makers. Monitoring the current state correctly is essential for national health promotion, and also for improvement of the investigation methods to apply country-by-country comparisons.