Objectives: To evaluate whether four types of low-cost interventions in the working environment can promote the small everyday lifestyle adaptations that can halt the epidemics of obesity and hypertension when maintained long term.
Design: A single-blind uninterrupted time-series intervention study consisting of four study periods: run-in (2 weeks), baseline (2 weeks), intervention (2 weeks), and after intervention 2 weeks).
Setting: University Medical Centre with over 11 000 employees, over 1000 hospital beds and over 2000 customers visiting the hospital restaurant each day.
Participants: Hospital staff and visitors.
Interventions: (1) Point-of-decision prompts on hospital elevator doors promoting stair use. (2) Point-of-purchase prompts in the hospital restaurant promoting reduced-salt soup. (3) Point-of-purchase prompts in the hospital restaurant promoting lean croissants. (4) Reversal of the accessibility and availability of diet margarine and butter in the hospital restaurant.
Main outcome measures: (1) Number of passages through 15 different parts of the hospital staircases. (2) Number and ratio of normal-salt and reduced-salt soup purchased. (3) Number and ratio of butter croissants and lean croissants purchased. (4) Number and ratio of diet margarine and butter purchased.
Results: Elevator signs increased the mean 24-h number of stair passages per measurement site (baseline: 992 ± 479 on week days and 208 ± 116 on weekend days) by 11.2% (95% CI 8.7% to 13.7%). This effect was maintained at least 2 weeks after the point-of-decision prompts were removed. Point-of-purchase prompts promoting low-salt soup and lean croissants did not result in altered purchase behaviour. The ratio between the purchase of margarine and butter was changed sevenfold (p<0.01) by reversing the positions of these products in the hospital restaurant.
Conclusions: Healthy lifestyle adaptations in the working environment can be effectively promoted by making healthy choices easier than unhealthy ones. Educational prompts at points-of-decision moderately increase stair climbing, but do not affect healthy food choices.
Protocol registration: Clinicaltrials.gov identifier number: NCT01574040.