Development and reliability testing for measures of psychosocial constructs associated with adolescent girls' calcium intake

J Am Diet Assoc. 2008 May;108(5):857-61. doi: 10.1016/j.jada.2008.02.014.

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.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adolescent Nutritional Physiological Phenomena* / drug effects
  • Adolescent Nutritional Physiological Phenomena* / physiology
  • Attitude to Health*
  • Bone Density / drug effects*
  • Bone Density / physiology
  • Bone Density Conservation Agents / administration & dosage*
  • Bone and Bones / metabolism
  • Calcium, Dietary / administration & dosage*
  • Child
  • Cluster Analysis
  • Cross-Sectional Studies
  • Dairy Products / supply & distribution
  • Female
  • Food Preferences
  • Health Knowledge, Attitudes, Practice*
  • Humans
  • Longitudinal Studies
  • Pilot Projects
  • Psychometrics
  • Social Perception
  • Statistics, Nonparametric
  • Surveys and Questionnaires

Substances

  • Bone Density Conservation Agents
  • Calcium, Dietary