Setting: There are many advantages to undertaking an individual participant data (IPD) meta-analysis compared to a summary data approach. IPD meta-analysis allows more flexible, complex statistical exploration of data, often increasing the number of clinical questions that can be addressed. In many contexts where summary data are insufficient or unavailable, an IPD analysis is the only feasible approach. However, procedures for obtaining IPD are time-consuming, resource intensive and often unsuccessful due to unavailability of data or concerns regarding patient privacy, collaboration and data sharing. Many initiatives promoting data sharing and data transparency within the pharmaceutical industry have developed quickly in recent years; such changes could have a large impact on IPD meta-analysis.
Background: From 1997 to present, the Cochrane Epilepsy Group has undertaken IPD meta-analyses and an IPD network meta-analysis is currently being updated. For all studies identified as eligible for these reviews, an IPD request was made to the lead or corresponding author or the sponsoring organisation if a study was industry-funded. Methods of contacting relevant data providers, requirements of an IPD request, content of data provided and success rates of IPD requests have changed dramatically over time. The launch of ClinicalStudyDataRequest.com (CSDR) platform and the SAS multi-sponsor data access environment in the last two years to allow researchers to request and remotely analyse de-identified IPD has been a significant change.
Discussion: IPD requests from 40 studies eligible for the IPD network meta-analysis from 2011 to the present will be discussed including requests pre-, during, and post the launch of CSDR. Advantages and practical issues of CSDR and the SAS data access system will be presented and the potential impact of these new initiatives on future IPD analyses will be discussed.