Validity of instruction leaflets for parents to measure their child's weight and height at home: results obtained from a randomised controlled trial

Abstract

ObjectivesTo compare the validity of parent-reported height, weight and body mass index (BMI) values of children (aged 4–10 years), when measured at home by means of newly developed instruction leaflets in comparison with simple estimated parental reports.DesignRandomised controlled trial with control and intervention group using simple randomisation.SettingBelgian children and their parents recruited via schools (multistage cluster sampling design).Participants164 Belgian children (53% male; participation rate 62%).InterventionParents completed a questionnaire including questions about the height and weight of their child. Parents in the intervention group received instruction leaflets to measure their child's weight and height. Classes were randomly allocated to the intervention and control groups. Nurses measured height and weight following standardised procedures up to 2 weeks after parental reports.Outcome measuresWeight, height and BMI category of the child were derived from the index measurements and the parental reports.ResultsMean parent-reported weight was slightly more underestimated in the intervention group than in the control group relative to the index weights. However, for all three parameters (weight, height and BMI), correlations between parental reports and nurse measurements were higher in the intervention group. Sensitivity for underweight and overweight/obesity was respectively, 75% and 60% in the intervention group, and 67% and 43% in the control group. Weighed κ for classifying children in the correct BMI category was 0.30 in the control group and was 0.51 in the intervention group.ConclusionsAlthough mean parent-reported weight was slightly more underestimated in the intervention than in the control group, correlations were higher and there was considerably less misclassification into valid BMI categories for the intervention group. This pattern suggests that most of the parental deviations from the index measurements were probably due to random errors of measurement and that diagnostic measures could improve by encouraging parents to measure their children's weight and height at home by means of instruction leaflets.

Agreement between parents’ proxy reports and children’s self-reports of physical activity and sedentary behavior in children aged 7 – 10 years in Vojvodina

“…Data on height and weight were based on the information given by parents. However, Huybrechts et al have shown that parents can give reliable information about height and weight of their children if they received instructions on how measurements should be performed [24,25].…”

Only children or siblings: who has higher physical activity and healthier weight?

“…The parents were thoroughly instructed how to measure their own body height and weight, as well as the height and weight of their offspring according to the illustrated instruction leaflets for home measurement. Parental home measurement of children's and adolescents' body height and weight [39][40][41][42] is considered to be sufficiently valid for calculating the BMI for a subsequent identification of childhood obesity [39,40]. The chronological age of all family members was calculated from the date of birth until the starting day of the PA monitoring.…”

“…Another potential limitation could be the home measurement of body weight and height of family members. However, parental home measurement of their children' weight and height according to researchers' instruction sheets are sufficiently accurate compared with laboratory measurement [40] for subsequent BMI calculations and classification of overweight and obesity [63], for example according to the WHO percentile growth charts. Moreover, none of the family members was given the cut-off values to classify body weight levels according to the WHO percentile growth charts for obesity classification.…”

Only children or children with siblings: who has greater physical activity and healthier weight?

“…The parents were thoroughly instructed how to measure their own body height and weight, as well as the height and weight of their offspring, according to the illustrated instruction lea ets for home measurement. Parental measurement of the body height and weight of their offspring at home [39][40][41][42] seems to be a su ciently valid method to identify overweight/obesity according to the calculated BMI compared with objective or laboratory/researcher measurements [39,40,43]. Although self-reported body height and weight is a widely used method for determining underweight, normal body weight, overweight, and obesity, previous studies point to possible inaccuracies compared with laboratory/researcher measurements and the absence of a uniform measurement consensus [43][44][45][46].…”

“…Another potential limitation could be the home measurement of the body weight and height of family members. However, parental home measurement of children's weight and height according to researchers' instruction sheets is su ciently accurate compared with laboratory measurement [40] for subsequent BMI calculations and the classi cation of overweight and obesity [66], for example according to the WHO percentile growth charts. Moreover, none of the family members was given the cut-off values to classify body weight levels according to the WHO percentile growth charts for the classi cation of obesity.…”