The challenge of evaluating complex interventions: a framework for evaluating media advocacy.

New health promotion and public health approaches such as media advocacy pose particular evaluation challenges. Evaluation is important to provide feedback to media advocacy practitioners on how to enhance their efforts, and to funders and researchers seeking to assess media advocacy's effectiveness as a health promotion strategy. The media advocacy evaluation literature contains some examples of promising evaluation approaches but is still evolving. A comprehensive framework for the evaluation of media advocacy is presented. Building on existing approaches to evaluation in media advocacy and on current thinking regarding evaluation in health promotion, it proposes a series of indicators and research methods for evaluating media advocacy at the levels of formative, process and outcome evaluation. The framework can be used to encourage strategic reflection on the media advocacy process, to guide evaluation of specific interventions, and to demonstrate to funders the importance and complexity of evaluation in this promising field.