Correspondence

Timing of surgical antibiotic prophylaxis administration: Complexities of analysis

Carrie Cartmill¹ , Lorelei Lingard^1,2 , Glenn Regehr^3,4 , Sherry Espin⁵ , John Bohnen^4,6 , Ross Baker⁷ and Lorne Rotstein^4,8

¹  The Learning Institute, The Hospital for Sick Children, Toronto, Canada

²  Department of Pediatrics, University of Toronto, Toronto, Canada

³  Wilson Centre for Research in Education, University Health Network, Toronto, Canada

⁴  Faculty of Medicine, University of Toronto, Toronto, Canada

⁵  Daphne Cockwell School of Nursing, Ryerson University, Toronto, Canada

⁶  Department of Surgery, St. Michael's Hospital, Toronto, Canada

⁷  Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada

⁸  Division of General Surgery, University Health Network, Toronto, Canada

author email corresponding author email

BMC Medical Research Methodology 2009, 9:43doi:10.1186/1471-2288-9-43

Published:	23 June 2009

Abstract

Background

The timing of prophylactic antibiotic administration is a patient safety outcome that is recurrently tracked and reported. The interpretation of these data has important implications for patient safety practices. However, diverse data collection methods and approaches to analysis impede knowledge building in this field. This paper makes explicit several challenges to quantifying the timing of prophylactic antibiotics that we encountered during a recent study and offers a suggested protocol for resolving these challenges.

Challenges

Two clear challenges manifested during the data extraction process: the actual classification of antibiotic timing, and the additional complication of multiple antibiotic regimens with different timing classifications in a single case. A formalized protocol was developed for dealing with incomplete, ambiguous and unclear documentation. A hierarchical coding system was implemented for managing cases with multiple antibiotic regimens.

Interpretation

Researchers who are tracking prophylactic antibiotic timing as an outcome measure should be aware that documentation of antibiotic timing in the patient chart is frequently incomplete and unclear, and these inconsistencies should be accounted for in analyses. We have developed a systematic method for dealing with specific problematic patterns encountered in the data. We propose that the general adoption of a systematic approach to analysis of this type of data will allow for cross-study comparisons and ensure that interpretation of results is on the basis of timing practices rather than documentation practices.