Validation of a Brief Questionnaire Against Direct Observation to Assess Adolescents' School Lunchtime Beverage Consumption.

OBJECTIVE: Beverage consumption is an important determinant of youth health outcomes. Beverage interventions often occur in schools, yet no brief validated questionnaires exist to assess whether these efforts improve in-school beverage consumption. This study validated a brief questionnaire to assess beverage consumption during school lunch.

METHODS: Researchers observed middle school students' (n = 25) beverage consumption during school lunchtime using a standardized tool. After lunch, students completed questionnaires regarding their lunchtime beverage consumption. Kappa statistics compared self-reported with observed beverage consumption across 15 beverage categories.

RESULTS: Eight beverages showed at least fair agreement (kappa [κ] > 0.20) for both type and amount consumed, with most showing substantial agreement (κ > 0.60). One beverage had high raw agreement but κ < 0.20. Six beverages had too few ratings to compute κ's.

CONCLUSIONS AND IMPLICATIONS: This brief questionnaire was useful for assessing school lunchtime consumption of many beverages and provides a low-cost tool for evaluating school-based beverage interventions.