Science should be replicable. The methods section in publications describe how research is conducted. This protocol is part of the REPEAT Initiative, a project that is attempting to replicate a sample of published research studies using information provided in the publications. REPEAT is focused on studies using observational healthcare data from electronic health records or administrative claims to generate scientific evidence. The goal is to better understand what information is missing in publications that prevents replication of the published results. This project will evaluate how commonly important decisions in research process design are not clearly reported as well as how lack of impacts ability to replicate study findings. Our results will inform future policies and guidelines for reporting on healthcare database research.
This protocol focuses on one sampled study: "Metformin and the incidence of viral associated cancers in patients with type 2 diabetes" by Hicks and colleagues. This paper compares the risk of cancers associated with viruses in patients with type 2 diabetes related to use of metformin (a drug to treat diabetes) for a diabetic population in the United Kingdom (UK) between 1988 and 2016. We will replicate this study based on methods reported in the publication.
This objective of this protocol is to replicate the study: "Metformin and the incidence of viral associated cancers in patients with type 2 diabetes" by Hicks et al based on methods reported in the publication and appendices. We have created a checklist of specific study implementation parameters based on a comprehensive catalogue outlined in a consensus paper endorsed by the International Society of Pharmacoepidemiology and the International Society of Pharmacoeconomics and Outcomes research. We will start by reviewing the paper to identify which parameters from the catalogue are reported. We will then replicate the study population and analyses based on the study design and implementation parameters extracted during review.
The Hicks paper compares the risk of viral associated cancers for patients with type 2 diabetes exposed to metformin between 1988 and 2016. We will focus on replicating the adjusted hazards ratio comparing the risk of viral associated cancers for time varying exposure to metformin. Patients were followed from new initiation of a non-insulin anti-diabetic agent until a first ever diagnosis of viral associated cancers, death from any cause, end of registration with the practice, or end of the study period (March 31, 2016), whichever occurred first. Risk of viral associated cancers was evaluated using a a time-dependent Cox proportional hazards model.
Primary diagnosis of viral associated cancer defined as a composite outcome (including hepatocellular carcinoma, Kaposi sarcoma, T-cell leukaemia, Non-Hodgkin's lymphoma, B and T cell lymphoma, cervical cancer, anal cancer, penile cancer, vaginal cancer, vulvar cancer, oropharyngeal and nasopharyngeal cancer).
Shirley Wang - Chief Investigator - Harvard University
Elisabetta Patorno - Collaborator - Brigham & Women's Hospital
Jessica Franklin - Collaborator - Brigham & Women's Hospital
Krista Huybrechts - Collaborator - Brigham & Women's Hospital
Sebastian Schneeweiss - Collaborator - Aetion, Inc
Jeremy Rassen - Chief Investigator - Aetion, Inc
Elizabeth Garry - Collaborator - Aetion, Inc