Scientist Spotlight: Dr. Kevin Schwartz – Advancing Antimicrobial Stewardship Research in Ontario


9 May 2019

On April 6, 2019, Public Health Ontario’s (PHO) Dr. Kevin Schwartz was presented with Association of Medical Microbiology and Infectious Disease Canada (AMMI) Young Investigator Award. This award recognizes a promising young investigator who has already made a substantial contribution to research in fields of infectious diseases or medical microbiology.

Kevin is an Antimicrobial Stewardship and Infection Prevention and Control Physician who has been working and conducting research with PHO for 2.5 years. His research focuses primarily on advancing public health evidence and knowledge in antimicrobial stewardship.

Antimicrobial stewardship promotes the appropriate use of antimicrobials to limit the development of antimicrobial resistant organisms.

Kevin is part of a PHO research program studying variability in antibiotic use. That research is generating a strong knowledge base on how to conduct antimicrobial stewardship and slow the growth of antimicrobial resistance to preserve the effectiveness of antibiotics for generations to come.

Regional Variability in Antibiotic Use

Rising rates of antimicrobial resistance are an urgent public health threat. The most important driver of resistance is unnecessary antibiotic use. In Canada, 92% of antibiotics are used outside of the hospital, yet we have done relatively little antimicrobial stewardship outside of the hospital. Understanding how we use antibiotics and how we can optimize their use in the community is important to help promote antimicrobial stewardship in Ontario.

Kevin and his colleagues at PHO, University of Toronto, and ICES are currently working on the research program OPTIMISE or the Ontario Program To Improve AntiMIcrobial USE. In this research program, funded by the Physician Services Incorporated Foundation, they are interested in collecting better data on community antibiotic use, identifying areas where there is more inappropriate use, and devising strategies to improve antibiotic use which will improve patient outcomes and slow the emergence of antimicrobial resistance. To date, the program has demonstrated substantial regional variability in antibiotic use across health regions in Ontario. This variability could not be explained by population differences suggesting there is room for improvement, particularly in the high use regions.1

Antibiotic Prescribing Variability amongst Physicians

A possible explanation for regional variability in antibiotic use is that it is driven by relatively small numbers of high prescribing physicians. The OPTIMISE research program is also looking at physician prescribing of antibiotics. Similar to the previous study, the program also observed a great deal of variability between different physicians within Ontario in terms of how many antibiotics they prescribe. Importantly, this variability could not be explained at all by the differences in patient populations. This suggests that what is driving a lot of antibiotic prescribing is not only patient need, but could also be influenced by physician habit in over prescribing.2

Overprescribing is also seen by some physicians prescribing antibiotics for longer durations than necessary. Kevin also completed some research on the variation of the proportion of antibiotic prescriptions that are for a prolonged duration. The study showed that the most important predictor that a physician is prescribing antibiotics for too long was the number of years since medical school graduation, highlighting opportunities to reduce antibiotic use in Ontario through prescribing shorter durations.3

Combating Antibiotic Resistance through Better Prescribing Practices

Informed by this work, Kevin and his research colleagues at Women’s College Hospital, Choosing Wisely Ontario, the Ontario Medical Association’s Section of General and Family Practice, and Health Quality Ontario have initiated a Canadian Institute for Health Research funded study on providing peer-comparison feedback to the highest antibiotic prescribing primary care physicians in Ontario.4 The goal of this study is to reduce some of the observed variability and reduce unnecessary antibiotic use. Physicians were randomized to receive one of two letter options: 

  • Half of the physicians received Choosing Wisely Canada materials on appropriate antibiotic initiation for acute respiratory infections.
  • The other half received guidelines on appropriate antibiotic durations. 

In December 2018, the letters were sent to 3000 physicians. Kevin and his colleagues will be evaluating the effect of these letters on antibiotic prescribing outcomes including antibiotic initiation and prolonged durations. This study has the potential to improve antibiotic prescribing amongst the highest prescribing physicians while generating important evidence that will inform antimicrobial stewardship programs locally, nationally, and internationally. 

For more information about Kevin’s research, please visit his Scientist Profile.

Photo of Dr. Kevin Schwartz

"A PHO appointment allows me to advance public health evidence and knowledge through studying antibiotic use in Ontario. Our research program will provide evidence to support a community antimicrobial stewardship program that will improve antibiotic use and slow the development of antimicrobial resistance."


  1. Schwartz KL, Achonu C, Brown KA, Langford B, Daneman N, Johnstone J, et al. Regional variability in outpatient antibiotic use in Ontario, Canada: a retrospective cross-sectional study. CMAJ Open. 2018;6(4):E445-52. Available from:
  2. Schwartz KL, Wilton AS, Langford BJ, Brown KA, Daneman  N, Garber G, et al. Comparing prescribing and dispensing databases to study antibiotic use: a validation study of the Electronic Medical Record Administrative data Linked Database (EMRALD).  J Antimicrob Chemother. 2019 Feb 25 [Epub ahead of print]. Available from: 
  3. Fernandez-Lazaro CI, Brown KA, Langford BJ, Daneman N, Garber G, Schwartz KL. Late-career physicians prescribe longer courses of antibiotics. Clin Infect Dis. 2019 Jan 7 [Epub ahead of print]. 
  4. Ontario Agency for Health Protection and Promotion (Public Health Ontario), Schwartz K; Canadian Institutes of Health Research; Health Quality Ontario. Providing antibiotic prescribing feedback to primary care physicians: the Ontario Program To Improve AntiMicrobial USE (OPTIMISE). Identifier NCT03776383. 2018 Dec 14 [cited 2019 Apr 25]. In: [Internet]. Bethesda, MD: National Library of Medicine; 2000 - . Available from:
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Updated 9 May 2019