New! EBOH Applied Methods Discussion Group

This is a reminder that all students, faculty and post-doctoral fellows are invited to participate in the new EBOH Applied Methods Discussion Group.

The objective of this group is to give us an opportunity to address and discuss real methodological challenges in our area of practice. The goal of each session will be to tackle one methodological challenge (or a small number of related challenges) that we encountered in our research, all the while putting a strong emphasis on the application and the implementation of related methods to overcome this problem. The group is intended to be student-run and student-led for the most part.

The first meeting is to take place on April 1st from 12-1pm in Purvis Room 24 where Dr. Aman Verma will share a current challenge in developing a study design to assess epinephrine dose given by paramedics and brain damage outcomes (see below for more details).

Refreshments will be served! 

If you have any questions or have an interest in sharing a methods related issue at a later date, please feel free to contact Daniala Weir (daniala [dot] weir [at] mail [dot] mcgill [dot] ca), Helen Cerigo (helen [dot] cerigo [at] mail [dot] mcgill [dot] ca), Bruno Riverin (Bruno [dot] riverin [at] mail [dot] mcgill [dot] ca) or Maxime Turgeon (maxime [dot] turgeon [at] mail [dot] mcgill [dot] ca).

Thanks,

Daniala, Helen, Bruno and Maxime

Epinephrine and the Survival Bias

Context: Urgence Santé is the organization in Quebec that runs, among other things, the ambulances. They have done some small research projects in the past, but they are looking to increase their research profile. They believe that they need to do an experimental trial to be taken seriously, and have settled on a topic of interest (the effect of epinephrine on brain damage), and have asked for help with calculating statistical power.
Study Question: We know that epinephrine, given by the paramedics at the time of “pick up”, increases survival-to-hospital, but we also suspect that it increases the probability of brain damage (by the time they are discharged). We want to know if a lower dose of epinephrine will decrease the probability of brain damage.

Study Design: Urgence Santé proposes that we do a randomized, controlled trial in which both arms of patients are given different doses of the epinephrine, and we compare the rate of brain damage in both groups.

Design issues: The design is complicated by the “two-phase” nature of the outcome: survival-to-hospital must occur for brain damage to occur. If a lower dose of epinephrine does not decrease the risk of brain damage, but it does decrease the rate of survival-to-hospital in those who would have got brain damage, then it would look like the lower dose decreases the risk of brain damage.

Solutions?: Urgence Santé needs help in designing a study to get an unbiased estimate of the effect of the lower dose of epinephrine on brain damage. They welcome observational designs, but also want results that can be clearly explained to field staff.