Fruit and vegetable shopping practices and social support scales: A validation.
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.
Baranowski
Tom
T
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
Missaghian
Mariam
M
Broadfoot
Alison
A
Watson
Kathy
K
Cullen
Karen
K
Nicklas
Theresa
T
Fisher
Jennifer
J
Baranowski
Janice
J
O'Donnell
Sharon
S
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