Purpose: To evaluate BestTreatments, an evidence-based decision support website for patients with chronic conditions (www.besttreatments.co.uk). In particular, to determine whether giving patients and doctors access to the same evidence-based sources of information can help them work in partnership to make decisions about health care.

BestTreatments is published by the British Medical Journal and is based on Clinical Evidence, the international source of evidence-based medicine for doctors. BestTreatments ranks treatments according to their effectiveness, based on the best research evidence. The site translates this evidence into language patients can understand and patients are involved in developing and reviewing content.

BestTreatments is available in the United Kingdom (through NHS Direct) and in the United States (through the websites of the Consumers Union and United Health Group). The evaluation also assessed whether patients in the UK and US had similar or differing needs around decision support.

Methods: Qualitative research methods involving 8 group discussions and 16 semi-structured interviews with patients in the US and UK. The sample of 80 patients was selected based on gender and disease. Areas covered musculo-skeletal conditions (eg back pain, osteoarthritis), women's health problems (eg fibroids, endometriosis), cardiovascular conditions and cancer. All respondents were asked to use the website for 45 minutes before coming to the interview.

Results: Both UK and US patients understand the concept of evidence-based information and value access to the same high-quality sources read by doctors. Patients found the BestTreatments content easy to understand, useful, trustworthy, supportive, accessible and well organised. These findings were almost universal, with a few minor negatives.

Many patients felt the site could enable them to make treatment decisions and facilitate dialogue with their doctors. The chief reason they felt able to do this was because the information came from a source that doctors read and would be taken seriously.

Conclusions: Providing patients with information that is based on the same sources of information that doctors read improves its credibility. In this qualitative evaluation, patients told us that they felt more confident to discuss treatment options with their doctor knowing that the information they had read on BestTreatments was based on evidence and known to their doctor. This research gives some helpful pointers for what makes effective decision support, from the patient point of view.