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Author: Lau, Christopher
Resulting in 2 citations.
1. Rendall, Michael S.
Weden, Margaret M.
Lau, Christopher
Brownell, Peter B.
Nazarov, Zafar
Fernandes, Meenakshi
Evaluation of Bias in Estimates of Early Childhood Obesity From Parent-Reported Heights and Weights
American Journal of Public Health 104,7 (July 2014): 1255-1262.
Also: http://ajph.aphapublications.org/doi/full/10.2105/AJPH.2014.302001
Cohort(s): Children of the NLSY79
Publisher: American Public Health Association
Keyword(s): Body Mass Index (BMI); Child Health; Data Quality/Consistency; Height; Obesity; Panel Study of Income Dynamics (PSID); Weight

Permission to reprint the abstract has not been received from the publisher.

Objectives: We evaluated bias in estimated obesity prevalence owing to error in parental reporting. We also evaluated bias mitigation through application of Centers for Disease Control and Prevention’s biologically implausible value (BIV) cutoffs.

Methods: We simulated obesity prevalence of children aged 2 to 5 years in 2 panel surveys after counterfactually substituting parameters estimated from 1999-2008 National Health and Nutrition Examination Survey data for prevalence of extreme height and weight and for proportions obese in extreme height or weight categories.

Results: Heights reported below the first and fifth height-for-age percentiles explained between one half and two thirds, respectively, of total bias in obesity prevalence. Bias was reduced by one tenth when excluding cases with height-for-age and weight-for-age BIVs and by one fifth when excluding cases with body mass–index-for-age BIVs. Applying BIVs, however, resulted in incorrect exclusion of nonnegligible proportions of obese children.

Conclusions: Correcting the reporting of children's heights in the first percentile alone may reduce overestimation of early childhood obesity prevalence in surveys with parental reporting by one half to two thirds. Excluding BIVs has limited effectiveness in mitigating this bias.

Bibliography Citation
Rendall, Michael S., Margaret M. Weden, Christopher Lau, Peter B. Brownell, Zafar Nazarov and Meenakshi Fernandes. "Evaluation of Bias in Estimates of Early Childhood Obesity From Parent-Reported Heights and Weights." American Journal of Public Health 104,7 (July 2014): 1255-1262.
2. Weden, Margaret M.
Brownell, Peter B.
Rendall, Michael S.
Lau, Christopher
Fernandes, Meenakshi
Nazarov, Zafar
Parent-Reported Height and Weight as Sources of Bias in Survey Estimates of Childhood Obesity
American Journal of Epidemiology 178,3 (1 August 2013): 461-473.
Also: http://aje.oxfordjournals.org/content/178/3/461.abstract
Cohort(s): Children of the NLSY79
Publisher: Johns Hopkins University Press
Keyword(s): Body Mass Index (BMI); Child Health; Data Quality/Consistency; Height; Obesity; Panel Study of Income Dynamics (PSID); Weight

Parental reporting of height and weight was evaluated for US children aged 2–13 years. The prevalence of obesity (defined as a body mass index value (calculated as weight (kg)/height (m)2) in the 95th percentile or higher) and its height and weight components were compared in child supplements of 2 nationally representative surveys: the 1996–2008 Children of the National Longitudinal Survey of Youth 1979 Cohort (NLSY79-Child) and the 1997 Child Development Supplement of the Panel Study of Income Dynamics (PSID-CDS). Sociodemographic differences in parent reporting error were analyzed. Error was largest for children aged 2–5 years. Underreporting of height, not overreporting of weight, generated a strong upward bias in obesity prevalence at those ages. Frequencies of parent-reported heights below the Centers for Disease Control and Prevention's (Atlanta, Georgia) first percentile were implausibly high at 16.5% (95% confidence interval (CI): 14.3, 19.0) in the NLSY79-Child and 20.6% (95% CI: 16.0, 26.3) in the PSID-CDS. They were highest among low-income children at 33.2% (95% CI: 22.4, 46.1) in the PSID-CDS and 26.2% (95% CI: 20.2, 33.2) in the NLSY79-Child. Bias in the reporting of obesity decreased with children's age and reversed direction at ages 12–13 years. Underreporting of weight increased with age, and underreporting of height decreased with age. We recommend caution to researchers who use parent-reported heights, especially for very young children, and offer practical solutions for survey data collection and research on child obesity.
Bibliography Citation
Weden, Margaret M., Peter B. Brownell, Michael S. Rendall, Christopher Lau, Meenakshi Fernandes and Zafar Nazarov. "Parent-Reported Height and Weight as Sources of Bias in Survey Estimates of Childhood Obesity." American Journal of Epidemiology 178,3 (1 August 2013): 461-473.