title: The use of a dietary quality score as a predictor of childhood overweight and obesity.
abstract: BACKGROUND
  The use of dietary quality scores/indices to describe diet quality in children has increased in the past decade. However, to date, few studies have focused on the use of these scores on disease outcomes such as childhood obesity and most are developed from detailed dietary assessments. Therefore, the aims of this study were: firstly to construct a diet quality score (DQS) from a brief dietary assessment tool; secondly to examine the association between diet quality and childhood overweight or obesity; thirdly we also aim to examine the associations between individual DQS components and childhood overweight or obesity.
  
  
  METHODS
  A secondary analysis of cross sectional data of a sample of 8,568 9-year-old children and their families as part of the Growing Up in Ireland (GUI) study. Subjects were drawn from a probability proportionate to size sampling of primary schools throughout Ireland over the school year 2007-2008. Height and weight were measured by trained researchers using standardised methods and BMI was classified using the International Obesity Taskforce cut-points. The DQS (un-weighted) was developed using a 20-item, parent reported, food frequency questionnaire of foods consumed over the past 24 h. Adjusted odds ratios for overweight and obesity were examined by DQS quintile, using the first quintile (highest diet quality) as the reference category.
  
  
  RESULTS
  The prevalence of normal weight, overweight and obese was 75, 19 and 6% respectively. DQS ranged from -5 to 25, higher scores indicated higher diet quality in the continuous score. In analyses adjusted for gender, parent's education, physical activity and T.V. viewing, child obesity but not overweight was significantly associated with poor diet quality: OR of 1.56 (95% CI 1.02 2.38) in the 5th compared to the 1st DQS quintile. Findings from individual food items were inconsistent.
  
  
  CONCLUSIONS
  The findings suggest that diet quality may be an important factor in childhood obesity. A simple DQS developed from a short dietary assessment tool is significantly associated with childhood obesity.
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, 4th Floor Western Gateway Building, Western Rd, Cork, Ireland. c.perry@ucc.ie.
authors.forename: Catherine P
authors.initials: CP
authors.lastname: Perry
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, 4th Floor Western Gateway Building, Western Rd, Cork, Ireland. eimear.keane@ucc.ie.
authors.forename: Eimear
authors.initials: E
authors.lastname: Keane
authors.affiliation: Economic and Social Research Institute (ESRI), Sir John Rogerson's Quay, Dublin 2, Ireland. richard.layte@esri.ie.|Department of Sociology, Trinity College Dublin, 3 College Green Dublin 2, Dublin 2, Ireland. richard.layte@esri.ie.
authors.forename: Richard
authors.initials: R
authors.lastname: Layte
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, 4th Floor Western Gateway Building, Western Rd, Cork, Ireland. t.fitzgerald@ucc.ie.|School of Mathematical sciences 1st floor Western Gateway Building, Western Rd, Cork, Ireland. t.fitzgerald@ucc.ie.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Fitzgerald
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, 4th Floor Western Gateway Building, Western Rd, Cork, Ireland. i.perry@ucc.ie.
authors.forename: Ivan J
authors.initials: IJ
authors.lastname: Perry
authors.affiliation: Department of Epidemiology and Public Health, University College Cork, 4th Floor Western Gateway Building, Western Rd, Cork, Ireland. j.harrington@ucc.ie.
authors.forename: Janas M
authors.initials: JM
authors.lastname: Harrington
mesh_terms: D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D004032:Diet / Q000706:statistics & numerical data*; D005247:Feeding Behavior; D005260:Female; D005518:Food Preferences / Q000523:psychology*; D063427:Food Quality; D015438:Health Behavior; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D008297:Male; D016017:Odds Ratio; D010290:Parents / Q000523:psychology*; D063766:Pediatric Obesity / Q000453:epidemiology* / Q000517:prevention & control; D015995:Prevalence