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DSECT/DSEN Monthly Seminar Series - May 25, 2017

“Contacting authors to retrieve individual patient data: a randomized controlled trial”

Presented by

Areti Angeliki Veroniki, PhD, MSc
Post-doctoral fellow at the Li Ka Shing Knowledge Institute, St. Michael’s Hospital 

Thursday, May 25 at 3-4pm EDT

Online via GoToWebinar (Space is limited)

Webinar Recording 



Individual participant data (IPD) meta-analysis is considered the ‘gold standard’ for exploring the effectiveness of interventions in different subgroups of patients. However, obtaining IPD is time consuming and contact with the original trial researchers is usually required. To date, there are no studies evaluating different strategies to optimize the process for retrieval of IPD. Empirical evidence suggests that IPD meta-analyses are often poorly reported in terms of proportion of IPD retrieved and reasons for non-availability of IPD. Although, there has been an improvement in access and awareness towards data sharing, the IPD retrieval rate has not improved over time.

Learning Objectives

  1. To discuss access to patient level data: benefits and challenges.
  2. To identify effective ways of obtaining individual patient data (IPD) from studies included in a systematic review.
  3. To examine the impact of providing a financial incentive to authors of RCTs that are eligible for a systematic review and network meta-analysis, versus usual contact strategies to obtain the IPD.
  4. To increase knowledge about what an IPD network meta-analysis (NMA) is, and when an IPD-NMA may be preferred compared to an aggregated data (AD) NMA.


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  9. Veroniki A.A., Straus S.E., Huda M., Hamid J., Yu C., Tricco A.C. Safety and effectiveness of long-acting versus intermediate-acting insulin for patients with type 1 diabetes: protocol for a systematic review and individual patient data network meta-analysis, BMJ Open; 2015; 30; 5(12):e010160. doi: 10.1136/bmjopen -2015-010160
  10. Veroniki A.A., Straus S.E., Huda M., Hamid J., Hemmelgarn B., Holroyd-Leduc J., Majumdar S.R., McAuley G., Tricco A.C. Comparative safety and effectiveness of cognitive enhancers for Alzheimer’s dementia: protocol for a systematic review and individual patient data network meta-analysis, BMJ Open; 2016; 6:e010251. doi:10.1136/bmjopen-2015- 010251
  11. Veroniki A.A., Soobiah C., Elliott M.J., Tricco A.C., Straus S.E. Methods For Network Meta-Analysis Using Individual Patient Data: Protocol for a Scoping Review, BMJ Open; 2015, 5:e007103. doi:10.1136/bmjopen-2014-007103
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