Finding and appraising qualitative evidence
Is the trial valid?< Back to search results
- Format Texts
- Language/s English
- Target Audience Further education
- EBM Stage 3 - Appraising evidence
- Duration <5 mins
- Difficulty Intermediate
Key Concepts addressed
- What is the problem and what are the options?
- 2-1a Comparison groups should be similar
- 2-1d People should not know which treatment they get
- 2-1g All should be followed up
Is low-energy laser an effective treatment for lateral epicondylitis? Do stretching programs prevent the development of contracture following stroke? Can the use of the flutter valve reduce postoperative respiratory complications? Rigorous answers to these questions can only be provided by properly designed, properly implemented clinical trials. Unfortunately, the literature contains both well performed trials which draw valid conclusions and badly performed trials which draw invalid conclusions. The reader must be able to distinguish between the two. This tutorial describes key features of clinical trials (or “methodological filters”) which confer validity.