Statistical Analysis plan of the Head Position in acute ischemic Stroke Trial pilot

Abstract

Background: The HEADPOST Pilot is a proof of concept, open, prospective, multicenter, international, cluster randomized, phase IIb controlled trial, with masked outcome assessment. The trial will test if lying flat head position initiated in patients within 12 hours of onset of acute ischemic stroke involving the anterior circulation increases cerebral blood flow in the middle cerebral arteries, as measured by transcranial Doppler For Review Only (TCD). The study will also assess the safety and feasibility of patients lying flat for ≥ 24 hours. The trial was conducted in centres in 3 countries, with ability to perform early TCD. A feature of this trial was that patients were randomized to a certain position according to the month of admission to hospital.

Objective: To outline in detail the predetermined statistical analysis plan (SAP) for HEADPOST Pilot study. Methods: All data collected by participating researchers will be reviewed and formally assessed. Information pertaining to the baseline characteristics of patients, their process of care, and the delivery of treatments will be classified, and for each item, appropriate descriptive statistical analyses are planned with comparisons made between randomized groups. For the outcomes, statistical comparisons to be made between groups are planned and described.

Results: This SAP was developed for the analysis of the results of the HEADPOST Pilot study to be transparent, available, verifiable, and predetermined before data lock.

Conclusions: We have developed a SAP for the HEADPOST Pilot study which is to be followed to avoid analysis bias arising from prior knowledge of the study findings.