title: Development and reliability testing for measures of psychosocial constructs associated with adolescent girls' calcium intake.
abstract: Early adolescence is an important period for assuring adequate calcium intake to achieve optimal bone health. This study was conducted to develop a measure of psychosocial constructs likely to be associated with young adolescent girls' consumption of high-calcium foods and to evaluate the test-retest reliability and factor structure of the measure. Methods involved: (a) generating a pool of items; (b) a cross-sectional pretest of the survey with a small group; (c) longitudinal administration of the revised survey with a larger group; and (d) statistical analysis to determine psychometric properties of the measures. Seventeen girls completed the pretest and debriefing, and 217 girls participated in the pilot test and test-retest (completion rate 95%). The study took place in Hawaii in late 2002. Coefficient alpha was used to test internal consistency and test-retest reliabilities were calculated. Cluster analyses of the items were performed to evaluate the factor structure of the measure. The resulting measure was a 55-item questionnaire to assess key psychosocial variables in three categories: Social and Environmental Factors (Availability, Social Influence); Attitudes and Preferences (Health Benefits; Preferences; Taste; Weight; Tolerance; Convenience); and Knowledge. The survey had high internal consistency reliability (alpha>.75) and good test-retest reliability (0.73 to 0.78 except for Knowledge, where Spearman's rho=0.41). The study developed a measure with high internal consistency and test-retest reliability to assess constructs that can be used in descriptive, prospective, and intervention research and as possible explanatory or mediating variables.
authors.affiliation: Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, 1518 Clifton Rd, NE, Room 530, Atlanta, GA 30322, USA. kglanz@sph.emory.edu <kglanz@sph.emory.edu>
authors.forename: Karen
authors.initials: K
authors.lastname: Glanz
authors.forename: Alana
authors.initials: A
authors.lastname: Steffen
mesh_terms: D000293:Adolescent; D017195:Adolescent Nutritional Physiological Phenomena / Q000187:drug effects / Q000502:physiology; D001294:Attitude to Health; D015519:Bone Density / Q000187:drug effects* / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D001842:Bone and Bones / Q000378:metabolism; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002648:Child; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D003611:Dairy Products / Q000600:supply & distribution; D005260:Female; D005518:Food Preferences; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008137:Longitudinal Studies; D010865:Pilot Projects; D011594:Psychometrics; D012938:Social Perception; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires
chemical_list: D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary