In clinical trials where patients are randomized between two treatment arms, not all patients comply with the treatment they were randomly assigned to. The reasons for (non)compliance may be associated with the outcome variable and thereby act as confounders. The standard way of analysing such trial
Secular changes in the quality of published randomized clinical trials in rheumatology
β Scribed by Catherine L. Hill; Michael P. LaValley; David T. Felson
- Publisher
- John Wiley and Sons
- Year
- 2002
- Tongue
- English
- Weight
- 54 KB
- Volume
- 46
- Category
- Article
- ISSN
- 0004-3591
- DOI
- 10.1002/art.512
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Objective
To assess the quality of published randomized clinical trials (RCTs) in rheumatology and to determine whether there has been improvement in quality between 2 time periods, 1987β1988 and 1997β1998.
Methods
Using MEDLINE and a hand search of selected rheumatology journals, we identified RCTs of adult rheumatic diseases published in English in 1987β1988 or 1997β1998. We examined trial quality with an expanded version of the Jadad scale, which assesses the adequacy of reported random sequence generation, allocation concealment, blinding, and analysis. All trials were read by 1 reviewer, with prior standardization using a random sample read by 2 reviewers. We also evaluated βhighββ versus βlowββimpact journals based on citation index.
Results
Two hundred forty RCTs (1987β1988 119 RCTs, 1997β1998 121 RCTs) were assessed. Results showed improvement in the quality of the trials, but the rates of reported random sequence generation, allocation concealment, power, and intentβtoβtreat analyses were persistently low. Low rates of reports of random sequence generation, allocation concealment, and intentβtoβtreat analyses were present even in the highβimpact journals.
Conclusion
There has been improvement in the quality of reporting of RCTs in rheumatology between 1987β1988 and 1997β1998. However, methodologic problems such as lack of allocation concealment, inadequate random sequence generation, lack of reporting of power, and lack of intentβtoβtreat analyses remain common. Many of these problems are established sources of bias in RCTs and are easily rectifiable.
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