Another problem is that while a study may be of high quality, it might not be appropriate to your area of practice.

A research study may exclude certain types of patients, (such as those with complex or multiple pathologies) in order to make the study ‘clean’. However, the nature of many areas of practice is that patients present with more than one problem, so an intervention which works in the study may not be appropriate.

For example, imagine a (fictional) study that looked at the effectiveness of Cognitive Behavioural Therapy (CBT) in patients with schizophrenia. In order to make the study easier to carry out the researchers decide to exclude clients with co-existing problems like alcohol or drug dependence. The study shows that CBT works. However, we would need to ask the question, can it be applied to a client group who have both schizophrenia, and drug/alcohol problems?