title: Investigating the accuracy of parentally reported weights and lengths at 12 months of age as compared to measured weights and lengths in a longitudinal childhood genome study.
abstract: Childhood obesity studies rely on parentally reported anthropometrics. However, the accuracy of such data has not been evaluated for 12-month-old children. Moreover, methods to improve the accuracy of reported data have not been assessed in prior studies.
  
  
  
  A total of 185 children enrolled in a northern Virginia childhood longitudinal cohort genomic study had parentally completed surveys at 12 months. Measured weights and lengths were recorded for the same children from their 12-month paediatrician visit. Weight for length percentiles were calculated using World Health Organization gender-specific growth charts. The agreement between reported and measured values was examined using Pearson's correlation, paired t-test and κ statistics. The interquartile outlier rule was used to detect and remove outliers.
  
  
  
  Parentally reported weight was strongly associated with measured weight at 12 months (r=0.90). There was only a moderate correlation between parentally reported and measured lengths (r=0.52) and calculated weight for length percentiles (r=0.65). After removing outliers from parentally reported data, there was an increase in correlation between parentally reported and measured data for weight (r=0.93), length (r=0.69) and weight for length percentiles (r=0.76). Outliers removed compared to all children included were more likely to have maternal education less than a bachelor's degree (p=0.007).
  
  
  
  After removal of outliers from reported data, there is a strong correlation between calculated reported and measured weight for length percentiles suggesting that this may be an effective method to increase accuracy when conducting large-scale obesity studies in young children where study costs benefit from using parentally reported data.
authors: Inova Translational Medicine Institute, Falls Church, Virginia, USA.
authors: Sahel
authors: S
authors: Hazrati
authors: Inova Translational Medicine Institute, Falls Church, Virginia, USA Inova Children's Hospital, Falls Church, Virginia, USA Pediatric Specialists of Virginia, Fairfax, Virginia, USA Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
authors: Suchitra K
authors: SK
authors: Hourigan
authors: Children's National Medical Center, Washington, District of Columbia, USA.
authors: Allison
authors: A
authors: Waller
authors: Inova Children's Hospital, Falls Church, Virginia, USA.
authors: Yvonne
authors: Y
authors: Yui
authors: Inova Children's Hospital, Falls Church, Virginia, USA.
authors: Nancy
authors: N
authors: Gilchrist
authors: Inova Translational Medicine Institute, Falls Church, Virginia, USA.
authors: Kathi
authors: K
authors: Huddleston
authors: Inova Translational Medicine Institute, Falls Church, Virginia, USA.
authors: John
authors: J
authors: Niederhuber
mesh_terms: D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D000068598:Data Accuracy; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D010290:Parents; D063766:Pediatric Obesity / Q000175:diagnosis* / Q000453:epidemiology; D012016:Reference Values; D011795:Surveys and Questionnaires; D014768:Virginia / Q000453:epidemiology; D014944:World Health Organization
keywords: Early childhood obesity; Self-reported data; Validation