K Uchino1, D Billheimer, S C Cramer. 1. Department of Neurology and Statistics, University of Washington, Seattle, WA, USA.
Abstract
UNLABELLED: Background and Purpose-We sought to study the range of entry criteria and baseline characteristics in acute stroke trials and to understand their effects on patient outcomes. METHODS: -Randomized, placebo-controlled therapeutic trials in patients with acute ischemic stroke were identified. Entry criteria, baseline clinical characteristics, and outcome were extracted for the placebo group of each trial. The relationship between key variables was then determined. RESULTS: -Across 90 placebo groups identified, there was great variation in entry criteria and outcome measures. This was associated with divergent outcomes; for example, in some studies most placebo group patients died, while in other studies nearly all had no disability. Entry criteria were significantly correlated with outcome; for example, higher age cutoff for study entry correlated with 3-month mortality. Entry criteria also predicted baseline clinical characteristics; for example, wider time window for study entry correlated directly with time to treatment and inversely with stroke severity (initial National Institutes of Health Stroke Scale score). Baseline characteristics predicted outcome. Greater stroke severity predicted higher 3-month mortality rate; despite this, successful thrombolytic trials have enrolled more severe strokes than most trials. The mean age of enrollees also predicted 3-month mortality and was inversely related to percentage of patients with 3-month Barthel Index score >/=95. The strongest predictors of 3-month mortality were obtained with multivariate models. CONCLUSIONS: -Acute stroke studies vary widely in entry criteria and outcome measures. Across multiple studies, differences in entry criteria, and the baseline clinical characteristics they predict, influence patient outcomes along a continuum. In some studies, enrolling a specific subset of patients may have improved the chances of identifying a treatment-related effect, while in others, such chances may have been reduced. These findings may be useful in the design of future stroke therapeutic trials.
RCT Entities:
UNLABELLED: Background and Purpose-We sought to study the range of entry criteria and baseline characteristics in acute stroke trials and to understand their effects on patient outcomes. METHODS: -Randomized, placebo-controlled therapeutic trials in patients with acute ischemic stroke were identified. Entry criteria, baseline clinical characteristics, and outcome were extracted for the placebo group of each trial. The relationship between key variables was then determined. RESULTS: -Across 90 placebo groups identified, there was great variation in entry criteria and outcome measures. This was associated with divergent outcomes; for example, in some studies most placebo group patients died, while in other studies nearly all had no disability. Entry criteria were significantly correlated with outcome; for example, higher age cutoff for study entry correlated with 3-month mortality. Entry criteria also predicted baseline clinical characteristics; for example, wider time window for study entry correlated directly with time to treatment and inversely with stroke severity (initial National Institutes of Health Stroke Scale score). Baseline characteristics predicted outcome. Greater stroke severity predicted higher 3-month mortality rate; despite this, successful thrombolytic trials have enrolled more severe strokes than most trials. The mean age of enrollees also predicted 3-month mortality and was inversely related to percentage of patients with 3-month Barthel Index score >/=95. The strongest predictors of 3-month mortality were obtained with multivariate models. CONCLUSIONS: -Acute stroke studies vary widely in entry criteria and outcome measures. Across multiple studies, differences in entry criteria, and the baseline clinical characteristics they predict, influence patient outcomes along a continuum. In some studies, enrolling a specific subset of patients may have improved the chances of identifying a treatment-related effect, while in others, such chances may have been reduced. These findings may be useful in the design of future stroke therapeutic trials.
Authors: An-Wen Chan; Jennifer M Tetzlaff; Peter C Gøtzsche; Douglas G Altman; Howard Mann; Jesse A Berlin; Kay Dickersin; Asbjørn Hróbjartsson; Kenneth F Schulz; Wendy R Parulekar; Karmela Krleza-Jeric; Andreas Laupacis; David Moher Journal: BMJ Date: 2013-01-08
Authors: J Mocco; Evan R Ransom; Ricardo J Komotar; Paulina B Sergot; Noeleen Ostapkovich; J Michael Schmidt; Kurt T Kreiter; Stephan A Mayer; E Sander Connolly Journal: J Neurol Date: 2006-10-24 Impact factor: 4.849
Authors: Steven C Cramer; Camille Fitzpatrick; Michael Warren; Michael D Hill; David Brown; Laura Whitaker; Karla J Ryckborst; Lawrence Plon Journal: Stroke Date: 2010-03-04 Impact factor: 7.914
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Authors: Pitchaiah Mandava; Santosh B Murthy; Melody Munoz; Dawn McGuire; Roger P Simon; Andrei V Alexandrov; Karen C Albright; Amelia K Boehme; Sheryl Martin-Schild; Sharyl Martini; Thomas A Kent Journal: Stroke Date: 2013-05-14 Impact factor: 7.914