TY - JOUR

T1 - Measuring Lunchtime Consumption in School Cafeterias Using Digital Images

T2 - A Validation Study

AU - Marcano-Olivier, Mariel

AU - Erjavec, Mihela

AU - Horne, Pauline J

AU - Viktor, Simon

AU - Pearson, Ruth

N1 - This article has been published in a revised form in Public Health Nutrition [https://doi.org/10.1017/S136898001900048X]. This version is free to view and download for private research and study only. Not for re-distribution, re-sale or use in derivative works. © copyright holder.

PY - 2019/7

Y1 - 2019/7

N2 - ObjectiveThe present study tested the validity of a digital image-capture measure of food consumption suitable for use in busy school cafeterias.DesignLunches were photographed pre- and post-consumption, and food items were weighed pre- and post-consumption for comparison.SettingA small research team recorded children’s lunchtime consumption in one primary and one secondary school over seven working days.ParticipantsA primary-school sample of 121 children from North Wales and a secondary-school sample of 124 children from the West Midlands, UK, were utilised. Nineteen children were excluded because of incomplete data, leaving a final sample of 239 participants.ResultsResults indicated that (i) consumption estimates based on images were accurate, yielding only small differences between the weight- and image-based judgements (median bias=0·15–1·64 g, equating to 0·45–3·42 % of consumed weight) and (ii) good levels of inter-rater agreement were achieved, ranging from moderate to near perfect (Cohen’s κ=0·535–0·819). This confirmed that consumption estimates derived from digital images were accurate and could be used in lieu of objective weighed measures.ConclusionsOur protocol minimised disruption to daily lunchtime routine, kept the attrition low, and enabled better agreement between measures and raters than was the case in the existing literature. Accurate measurements are a necessary tool for all those engaged in nutrition research, intervention evaluation, prevention and public health work. We conclude that our simple and practical method of assessment could be used with children across a range of settings, ages and lunch types.

AB - ObjectiveThe present study tested the validity of a digital image-capture measure of food consumption suitable for use in busy school cafeterias.DesignLunches were photographed pre- and post-consumption, and food items were weighed pre- and post-consumption for comparison.SettingA small research team recorded children’s lunchtime consumption in one primary and one secondary school over seven working days.ParticipantsA primary-school sample of 121 children from North Wales and a secondary-school sample of 124 children from the West Midlands, UK, were utilised. Nineteen children were excluded because of incomplete data, leaving a final sample of 239 participants.ResultsResults indicated that (i) consumption estimates based on images were accurate, yielding only small differences between the weight- and image-based judgements (median bias=0·15–1·64 g, equating to 0·45–3·42 % of consumed weight) and (ii) good levels of inter-rater agreement were achieved, ranging from moderate to near perfect (Cohen’s κ=0·535–0·819). This confirmed that consumption estimates derived from digital images were accurate and could be used in lieu of objective weighed measures.ConclusionsOur protocol minimised disruption to daily lunchtime routine, kept the attrition low, and enabled better agreement between measures and raters than was the case in the existing literature. Accurate measurements are a necessary tool for all those engaged in nutrition research, intervention evaluation, prevention and public health work. We conclude that our simple and practical method of assessment could be used with children across a range of settings, ages and lunch types.

KW - Cafeteria

KW - Consumption

KW - Digital photography

KW - Nutrition

KW - School

KW - Validation

KW - Visual estimation

U2 - 10.1017/S136898001900048X

DO - 10.1017/S136898001900048X

M3 - Article

VL - 22

SP - 1745

EP - 1754

JO - Public Health Nutrition

JF - Public Health Nutrition

SN - 1368-9800

IS - 10

ER -