Introduction: Prevalence of obesity has been on the increase in recent years. In contrast to obesity in adulthood, childhood obesity is still not uniformly defined. This results in problems to determine the need for medical rehabilitation.
Methods: The Kiel Obesity Prevention Study (KOPS) is a cross-sectional study assessing the nutritional status of 5-7 year-old German children. Three different definitions of overweight and obesity (German reference data for triceps skinfold thickness [90(th) percentile] and BMI [90(th)/97(th) percentile] as well as an international standard for BMI [extrapolated to levels of adults]) were applied to 1,643 children of KOPS enrolled between 1996 and 2000 (19 % of all first-graders in Kiel in this period).
Results: The prevalence of overweight varies from 9 to 21 % depending on the applied definition. With the definitions of overweight and obesity based on newer BMI percentiles a part of overweight children are not classified as such. The present state of art is that there is only a need for obese children for medical rehabilitation: these are 3.3 and 3.5 % of 5-7 year-old children in Kiel, respectively.
Conclusions: Experts should work out an agreement concerning a uniform definition of childhood obesity. Currently, medical rehabilitation services are offered only to extremely obese children. There is a need for more and earlier preventive measures.