Toward the economic evaluation of participatory approaches in health promotion: lessons from four German physical activity promotion projects.

Health promotion increasingly employs participatory approaches, but the question arises whether the likely higher costs of participation also translate into greater benefits. This article takes a first step toward a full health economic evaluation by comprehensively reporting the costs of a specific participatory approach, Cooperative Planning, in a German research consortium to promote physical activity. We conducted a costing analysis of Cooperative Planning at 22 sites across six settings.