Obesity in school children and their parents in southern Iran.

Data on school children and their parents in Shiraz, Iran, were used to develop power-type obesity indices, Ip = W/Hp. The optimal value of p was 2.5 for children and 1 for their parents. The smoothed obesity index by age charts are presented using the HRY non-parametric method, which is likely to provide normal ranges of fatness measures for clinical work in Iran. The familial pattern of parent-child obesity was investigated by a preliminary analysis of the distribution of obesity using arbitrarily chosen cut-off points to define obese, normal and lean parents. Then principal component analysis (PCA) was applied to analyse the data as continuous variables, which is found to be an efficient sophisticated technique in clarifying the structure of familial obesity. The analysis also shows no indication of clustering of super-obese families. A structural analysis indicates a direct relationship between obesity of parents and children.