General practitioners cannot rely on reported weight and height of children.

Aim: The aim of this study is to investigate the differences between reported and measured weight and height for underweight, normal-weight, and overweight children, particularly in a general practitioner setting.

Background: Screening, signaling, and treatment of childhood obesity by the general practitioner depends on accurate weight and height measurements.

Methods: Data on reported and measured weight and height from a cohort including 715 normal-weight and overweight children aged 2-17 were used. Means of reported and measured weight and height were compared using the paired T-test.

Findings: Of the 715 included children, 17.5% were defined as being underweight, 63.2% normal-weight, and 19.3% overweight according to direct measured height and weight. In the age group 2-8 years, parents of underweight children reported a significantly higher weight than measured weight [mean differences (MD) 0.32 kg (0.02, 0.62)], whereas parents of overweight young children reported a significantly lower weight [MD -1.08 kg (-1.77, -0.39)]. In the age group 9-17 years, normal-weight [MD -0.51 kg (-0.79, -0.23)] and overweight children [MD -1.28 kg (-2.08, -0.47)] reported a significantly lower weight than measured weight.

Conclusions: General practitioners cannot rely on reported weight and height measures from parents and children. In case of suspected under- or overweight in children, it should be advised to measure weight and height in general practice.