Potential impact of changes in administrative database coding methodology on research and policy decisions: an example from the Ontario Health Insurance Plan

  • Ana P. Johnson
  • Brian Milne
  • Marlo Whitehead
  • Jianfeng Xu
  • Joel L. ParlowEmail author

To the Editor,

Reliable and complete data are needed for monitoring and evaluating the provision of healthcare services, physician and hospital remuneration, and service planning.1 In the Canadian province of Ontario, the Institute for Clinical Evaluative Sciences (ICES) houses healthcare administrative databases obtained from physician and hospital billing records from a single-payer public health insurance physician reimbursement system, the Ontario Health Insurance Plan (OHIP). These databases may be linked, using unique patient identifiers, to a number of other databases. Such databases, containing data points such as procedures, diagnostic codes, as well as costing and resource utilization, are often used for research purposes that may subsequently inform clinical care and policy decisions. Within the medical specialties, a vast array of data related to the field of anesthesiology and perioperative medicine are accessible.2,3Nevertheless, researchers need to be wary of the...



This study was supported by the Institute for Clinical Evaluative Sciences (ICES), which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC). The opinions, results, and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by ICES or the MOHLTC is intended or should be inferred. We would like to acknowledge Elizabeth VanDenKerkhof, Dana Thompson-Green, Emilie Piarenosa, and Mahrukh Abid for their contributions to the project.

Conflicts of interest

None declared.

Editorial responsibility

This submission was handled by Dr. Hilary P. Grocott, Editor-in-Chief, Canadian Journal of Anesthesia.


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Copyright information

© Canadian Anesthesiologists' Society 2019

Authors and Affiliations

  1. 1.Institute for Clinical Evaluative Sciences (ICES) Queen’sQueen’s UniversityKingstonCanada
  2. 2.Department of Public Health SciencesQueen’s UniversityKingstonCanada
  3. 3.Department of Anesthesiology and Perioperative MedicineQueen’s UniversityKingstonCanada

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