Decision aids (DAs) are interventions designed to help people make specific and deliberative choices among options by providing information about the options and outcomes that is relevant to a person's health status.

There is an ongoing discussion about the quality of DAs. The present article provides an overview on systematic approaches using various quality criteria. However, these evaluation guides are not yet implemented. Up to now quality assessment of DAs is often limited to the evidence on efficacy through controlled trials using single-outcome measures. Since DAs are multi-component interventions, single-outcome trials are not sufficient for complete quality assessment. Consideration of theoretical founding and the development process is required. In an earlier paper we proposed a novel concept of quality to meet this challenge. We introduced MATRIX a guide for quality assessment of DAs aimed at disclosing the rationale behind underpinning theories, methods, and goals of a DA.

The present paper reports how the development of MATRIX progressed including results of pre-testing and a feasibility study. We present the revised version of MATRIX, explain its basic concept, and describe the way to use it.