title: Fruit and vegetable shopping practices and social support scales: A validation.
abstract: OBJECTIVE
  To assess the psychometric characteristics of new scales of shopping practices and social support for purchasing fruits and vegetables.
  
  
  METHODS
  Participants were recruited in front of diverse grocery stores. Telephone data collection was done on 2 occasions, separated by 6 weeks.
  
  
  METHODS
  166 food shoppers with children at home participated.
  
  
  METHODS
  New scales of food shopping practices and social support for purchasing fruits and vegetables were psychometrically analyzed and related to a measure of home fruit or vegetable availability as a test of construct validity.
  
  
  METHODS
  Both classical test and item response theory procedures were used. Correlations related the new measures to home fruit and vegetable availability.
  
  
  RESULTS
  Single dimension scales were specified for fruit and vegetable shopping practices (35% of the variance), fruit purchase social support (53% of the variance), and vegetable purchase social support (52% of the variance). Item response theory difficulty estimates varied from -0.64 to 0.73 for fruit and vegetable shopping practices, from -0.55 to 0.33 for fruit purchase social support, and from -0.55 to 0.34 for vegetable social support. Each scale significantly correlated with home fruit and vegetable availability (construct validity), even after controlling for social desirability of response (0.19 for shopping practices, 0.37 for fruit purchasing social support, and 0.28 for vegetable purchasing social support). Person separation reliability was 0.80 for food shopping practices, 0.74 for fruit purchasing social support, and 0.73 for vegetable purchasing social support.
  
  
  CONCLUSIONS
  The scales performed well.
  
  
  CONCLUSIONS
  These scales are now available to help better understand fruit and vegetable shopping practices, fruit purchase social support, and vegetable purchase social support.
authors.affiliation: Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates St, Room 2038, Houston, TX 77030-2600, USA. tbaranow@bcm.tmc.edu
authors.forename: Tom
authors.initials: T
authors.lastname: Baranowski
authors.forename: Mariam
authors.initials: M
authors.lastname: Missaghian
authors.forename: Alison
authors.initials: A
authors.lastname: Broadfoot
authors.forename: Kathy
authors.initials: K
authors.lastname: Watson
authors.forename: Karen
authors.initials: K
authors.lastname: Cullen
authors.forename: Theresa
authors.initials: T
authors.lastname: Nicklas
authors.forename: Jennifer
authors.initials: J
authors.lastname: Fisher
authors.forename: Janice
authors.initials: J
authors.lastname: Baranowski
authors.forename: Sharon
authors.initials: S
authors.lastname: O'Donnell
mesh_terms: D000328:Adult; D003132:Commerce / Q000379:methods*; D003430:Cross-Sectional Studies; D004034:Diet Surveys; D005260:Female; D005638:Fruit; D007722:Health Knowledge, Attitudes, Practice; D006293:Health Promotion; D006801:Humans; D008297:Male; D009747:Nutritional Physiological Phenomena; D052756:Nutritional Sciences / Q000193:education; D011594:Psychometrics; D020377:Self Efficacy; D012944:Social Support; D014675:Vegetables