Probing the Effective Treatment Thresholds for Alteplase in Acute Ischemic Stroke With Regression Discontinuity Designs.
Abstract
Randomized Controlled Trials (RCTs) are considered the gold standard for measuring
the efficacy of medical interventions. However, RCTs are expensive, and use a limited
population. Techniques to estimate the effects of stroke interventions from observational
data that minimize confounding would be useful. We used regression discontinuity design
(RDD), a technique well-established in economics, on the Get With The Guidelines-Stroke
(GWTG-Stroke) data set. RDD, based on regression, measures the occurrence of a discontinuity
in an outcome (e.g., odds of home discharge) as a function of an intervention (e.g.,
alteplase) that becomes significantly more likely when crossing the threshold of a
continuous variable that determines that intervention (e.g., time from symptom onset,
since alteplase is only given if symptom onset is less than e.g., 3 h). The technique
assumes that patients near either side of a threshold (e.g., 2.99 and 3.01 h from
symptom onset) are indistinguishable other than the use of the treatment. We compared
outcomes of patients whose estimated onset to treatment time fell on either side of
the treatment threshold for three cohorts of patients in the GWTG-Stroke data set.
This data set spanned three different treatment thresholds for alteplase (3 h, 2003-2007,
N = 1,869; 3 h, 2009-2016, N = 13,086, and 4.5 h, 2009-2016, N = 6,550). Patient demographic
characteristics were overall similar across the treatment thresholds. We did not find
evidence of a discontinuity in clinical outcome at any treatment threshold attributable
to alteplase. Potential reasons for failing to find an effect include violation of
some RDD assumptions in clinical care, large sample sizes required, or already-well-chosen
treatment threshold.
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https://hdl.handle.net/10161/21579Published Version (Please cite this version)
10.3389/fneur.2020.00961Publication Info
Naidech, Andrew M; Lawlor, Patrick N; Xu, Haolin; Fonarow, Gregg C; Xian, Ying; Smith,
Eric E; ... Kording, Konrad P (2020). Probing the Effective Treatment Thresholds for Alteplase in Acute Ischemic Stroke
With Regression Discontinuity Designs. Frontiers in neurology, 11. pp. 961. 10.3389/fneur.2020.00961. Retrieved from https://hdl.handle.net/10161/21579.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Roland Albert Matsouaka
Associate Professor of Biostatistics & Bioinformatics
Ying Xian
Adjunct Associate Professor in the Department of Neurology
Haolin Xu
Biostatistician, Senior
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