Interrater reliability of the modified Jadad quality scale for systematic reviews of Alzheimer's disease drug trials

Drug therapies for Alzheimer's disease (AD) have been evaluated in clinical trials over the past 2 decades. Systematic reviews of AD drug trials can s hed more light on the efficacy of pharmaceutical interventions. The modifie d Jadad scale can be used to assess the quality of trial reports that are c andidates for inclusion in these systematic reviews. The interrater reliabi lity of the modified Jadad scale was examined during such a review. Three b linded reviewers rated the quality of 42 AD drug trial reports: the intracl ass correlation coefficient was 0.90. The modified Jadad scale appears to b e a useful tool for AD research because of the very good interrater reliabi lity. Also, it is composed of items that are well suited to the specific di sease characteristics of AD. Further research should focus on the validity of this instrument. Copyright (C) 2001 S. Karger AG, Basel.