Creation of a Merged Harmonized Large Database of Subject-Level Data from Acute Secondary Prevention Studies in Minor Non-Cardioembolic Stroke or TIA.

Introduction: Prevention of early recurrence of ischemic stroke after an initial event is a clinically important problem that has been the subject of a number of large clinical trials testing acute treatment interventions. Datasets of clinical trials provide a rich source of information beyond the primary research questions addressed. Merging of datasets, providing greater statistical power and wider applicability for novel exploratory analyses, requires careful harmonization of similar data elements. Methods: The Acute Stroke or Transient Ischaemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES), Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke Trial (POINT), and Acute STroke or Transient IscHaemic Attack Treated with TicAgreLor and ASA for PrEvention of Stroke and Death (THALES) trials each examined the effects of early administration of enhanced antiplatelet therapy versus aspirin alone within 12-24 hours following minor ischemic stroke or transient ischemic attack. Results: The datasets of these 3 trials have been harmonized and merged into a single large data table comprising 26319 subjects with 75 clinical and demographic variables, 196 concomitant medication descriptors, and event flags and event timing variables for 20 clinical outcome events. A high degree of data completeness was attained for most variables. Conclusion: This merged data table provides a powerful resource of pooled clinical trial data to enable future large-scaled analyses for the study of stroke recurrence risks, and is now curated and available for other investigators.