Is the trial valid?
An article from the PEDro database on assessing the validity of a study.Key Concepts addressed:
- 2-2 Comparison groups should be similar
- 2-5 People should not know which treatment they get
- 2-7 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.