In the paper, the economic evaluation method is applied to a prevention intervention for healthcare workers. The intervention consists in wearing a compression stocking to avoid the risk of chronic venous insufficiency. The economic evaluation estimates the loss of productivity due to inability at work (presenteeism) and the efficacy when prevention is adopted. The results of the randomised controlled trial showed that, in the long-run, intervention group suffer less for inability due to prolonged standing posture. Consequently, the productivity loss due to presenteeism is lower compared to the control group, thanks to the compression stocking. Prevention, in this regard, can reduce the costs for presenteeism considering both the social and the National Healthcare Service perspectives.