Stage-matched workplace intervention improves reported diet in Sri Lankan cluster trial

A cluster-randomised trial in Sri Lanka’s Galle District assessed whether tailoring a workplace dietary intervention to office workers’ baseline stage of change improved dietary behaviour. Intervention clusters received stage-matched support, while control clusters received no intervention. Outcomes at three months were changes in behavioural stage, the primary outcome, and healthy dietary intake, the secondary outcome. Assessments used a staging algorithm and a 24-hour dietary recall supported by a picture guide and computer software.

Behavioural stage improved in both intervention (p<0.001) and control groups (p=0.04). The intervention group also showed improvements in cereal, fruit, and vegetable intake and reduced unhealthy food intake (p<0.001). In logistic regression analyses, intervention receipt predicted improvement in behavioural stage (OR 12.2) and healthy dietary intake (OR 25.3), both p<0.001.

The findings support further evaluation of readiness-tailored dietary programmes in workplaces, but do not establish reductions in non-communicable disease risk. Follow-up lasted only three months, and dietary intake was assessed by recall rather than clinical outcomes. The supplied report omits sample size, confidence intervals, absolute dietary changes, and details of how clustering was handled, limiting assessment of precision and clinical magnitude. The authors recommend pragmatic evaluation across other settings.