PUBLIC HEALTH NUTRITION AND EPIDEMIOLOGY
The process evaluation of two interventions aimed at portion size in worksite cafeterias
Article first published online: 3 DEC 2011
© 2011 The Authors. Journal of Human Nutrition and Dietetics © 2011 The British Dietetic Association Ltd
Journal of Human Nutrition and Dietetics
Volume 25, Issue 2, pages 180–188, April 2012
How to Cite
Vermeer, W. M., Leeuwis, F. H., Koprulu, S., Zouitni, O., Seidell, J. C. and Steenhuis, I. H. M. (2012), The process evaluation of two interventions aimed at portion size in worksite cafeterias. Journal of Human Nutrition and Dietetics, 25: 180–188. doi: 10.1111/j.1365-277X.2011.01219.x
- Issue published online: 19 MAR 2012
- Article first published online: 3 DEC 2011
- portion size;
- process evaluation;
- worksite cafeteria
How to cite this article Vermeer W.M., Leeuwis F.H., Koprulu S., Zouitni O., Seidell J.C. & Steenhuis I.H.M. (2012) The process evaluation of two interventions aimed at portion size in worksite cafeterias. J Hum Nutr Diet.25, 180–188
Background: In a previous study, the effectiveness of introducing a small meal in addition to the existing size and a proportional pricing strategy have been assessed in Dutch worksite cafeterias. To assess the degree of implementation and to inform the design of future interventions, the present study aimed to describe the process evaluation of both interventions.
Methods: Process evaluation components from Baranowski and Stables, and Rogers (i.e. Recruitment, Maintenance, Context, Resources, Implementation, Exposure, Contamination, and Continued use) were chosen as a theoretical basis. The process evaluation involved qualitative (e.g. structured observations, semi-structured interviews) and quantitative data (e.g. consumer questionnaires) collected from 17 intervention and eight control worksite cafeterias.
Results: In all intervention cafeterias, two portion sizes were offered. The pricing instructions were followed in 13 intervention cafeterias. The cafeterias managers indicated that they did not consider offering large and small meals as being complex, risky or time-consuming to implement. Some managers perceived the consumer demand as high, others as (too) low. One year after the study had ended, nine of the intervention cafeterias had continued (at least partly) to follow the protocol.
Conclusions: Offering a smaller portion size in addition to the existing size, as well as proportional pricing, was generally implemented as prescribed by the protocol and can be considered promising in terms of continued use. However, additional efforts are needed to make the intervention more effective in motivating consumers to replace their large portion with a small portion.