Follow-up phone calls increase nutrient intake estimated by three-day food diaries in 13-year-old participants of the Raine study

Aim: Our primary objective was to determine the effect of follow-up phone calls on estimated nutrient intakes obtained by three-day food diaries from 13-year-old adolescents. Methods: Food diaries were recorded using household measures and entered into a dietary analysis software program, before and after follow up by telephone. A sample of 340 participants aged 13 years born into the Western Australian Pregnancy Cohort (Raine) Study, a population-based longitudinal cohort followed from 16 to 20 weeks' gestation to 13 years of age (current follow up). After face-to-face instruction, participants completed three-day food diaries at home and returned them by post. Follow-up telephone calls were made to each participant to improve data collection response and to verify missing details in the food diaries. Nutrient intakes before and after telephone follow up were compared using Student's t-tests in spss. Results were also compared with those of the Child and Adolescent Physical Activity and Nutrition survey. Results: Follow-up phone calls significantly increased the estimated intake of total kilojoules, water, total carbohydrates, sugars and magnesium (P < 0.05). Conclusion: These results indicate the importance of follow-up phone calls to obtain missing details in three-day food diaries completed by adolescents.