(Stroke. 2001;32:1048.)
© 2001 American Heart Association, Inc.
Letters to the Editor |
Authors Should Be Accurate When Describing Study Design
Academic Unit of Psychiatry and Behavioral Sciences, University of Leeds, Leeds, UK,
Clinical Trials Research Unit, University of Auckland, Auckland, New Zealand
To the Editor:
Kimura and colleagues,1 in presenting their study on the impact of nortriptyline on cognitive impairment after stroke, do not describe clearly the research design they have used. In the paper’s title and in the text, they report the study as a randomized placebo-controlled trial, but they also describe it as a secondary analysis of data pooled from 2 previous trials—in other words, a meta-analysis. Although the paper does not directly reference the trials that were included, the details of research grants which supported the present work match those for 2 previously published trials,2 3 as do many of the methodological details. There are discrepancies, for example, in descriptions of the trials’ entry criteria and in the numbers of subjects included, but overall the evidence suggests that the present paper reports a meta-analysis of these 2 trials.
We need to be clear which sort of study this is for 2 reasons. First, if it is a meta-analysis, then it may produce misleading results if it is not based on all available trials or if it relies on subgroup analysis. In this case, the data on cognitive impairment were obtained as secondary outcomes in only 2 previous trials, and the present article is based on a subgroup analysis of results for some of the patients on whom these secondary outcomes were available. There is a strong possibility that such selectivity can lead to erroneous conclusions, which is not sufficiently acknowledged in the paper.
Second, Kimura and colleagues present results on
Department of Psychiatry, University of Iowa, robert-robinson@uiowa.edu
University of Iowa, Nippon Medical School, Tokyo, Japan
The University of Iowa, Iowa City, Iowa