Optimizing blood pressure in acute intracerebral hemorrhage: protocol for a prospective individual participant data meta-analysis of the four INTERACT trials

The Optimising Blood Pressure in acute intracerebral hemorrhage (ICH) study aims to conduct an IPDMA of pooling the four INTERACT trial to provide reliable information on the optimal blood pressure (BP) treatment target for patients with acute ICH. This protocol outlines the methods for the systematic review, research questions, and the approach to statistical analysis. An intention-to-treat principle (ITT) will be applied in all analyses. Baseline characteristics will be summarised by treatment group. BP lowering treatment effect on the outcomes will be analysed by means of an ordinal logistic regression, and on the secondary and safety outcomes will be analysed by means of a binary logistic regression. Primary outcome is an ordinal distribution of modified Rankin Scale (mRS) scores at 90 days; secondary outcomes include change (absolute and relative, defined as an increase by >33%) in hematoma volume from the baseline and 24 hours CT scans and safety events within 90 days. Publication policyThis policy is to be inclusive and follows that outlined for a prospective meta-analysis.1 This policy requires the identification of the lead investigator responsible for each randomized controlled trial (RCT) - known as a Principle Investigator (PI)- as well as up to four additional investigators from each RCT, members of the Trial Management Group or Trial Steering Committee for each RCT, and the methodologists/statisticians involved in the meta-analysis. ProtocolUp to five investigators from each INTERACT trial may be included as co-authors of this protocol if they fulfil the ICMJE criteria of contributing authors, and they will be listed alphabetically by surname. The methodologists and statisticians involved in the design of INTERACT individual participant data meta-analysis will be co-authors. Each RCT may provide an unlimited number of non-author contributors, who are most likely to be members of each RCTs Trial Management Group or Trial Steering Committee. The criteria for determining who is a contributing author or a non-author contributor follow ICMJE definitions: www.icmje.org/recommendations/browse/roles-and-responsibilities/defining-the-role-of-authors-and-contributors.html. All publications will name contributing authors as well as the attribution, "on behalf of the INTERACT collaborators." Any report of the INTERACT IPDMA will be circulated to co-authors for comment and approval before submission for publication. All co-authors must have participated fully in manuscript preparation and editing.