The researchers assessed the methodological quality of all randomized clinical trials published in the journal Gastroenterology as original articles from 1964 to 2000.
The findings of the study were published in the latest issue of the journal.
A total of 383 relevant trials were identified.
The methodological quality (randomization and blinding), sample size, publication year, and disease area were extracted from each study.
Changes during the study period were analyzed by analysis of variance, with adjustments for potential confounders.
|62% of the trials were double-blinded.
| Gastroenterology |
The team found that 42% of all trials reported adequate generation of the allocation sequence, 39% reported adequate allocation concealment, and 62% were double blind.
The reported methodological quality was found to improve significantly in the mid-1990s.
Author Lise L. Kjaergard said on behalf of fellow colleagues, "The present study shows a positive development, but the reported methodological quality of trials can still be improved."