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The adaptation of AABACUS for quality improvement in laboratory workflow analysis ('L-AABACUS')
  1. Shehnaz Khan1,
  2. Carol C Cheung1,2
  1. 1 Laboratory Medicine Program, University Health Network, Toronto, Canada
  2. 2 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
  1. Correspondence to Dr Carol C Cheung, Laboratory Medicine Program, University Health Network, Toronto, ON M5G 2C4, Canada; c.cheung{at}


The ability to effectively monitor key indicators is important for continuous quality improvement in laboratory immunohistochemistry. This article deals specifically with laboratory turnaround time (TAT) as a key delivery indicator and the impact of laboratory workflow on laboratory TATs. While our laboratory has traditionally relied on the manual calculation of slide-TAT (S-TAT) to monitor delivery, we have determined that automated calculation of case-TAT (C-TAT) would be superior as a delivery indicator. AABACUS (Automatable Activity-Based Approach to Complexity Unit Scoring) is an activity-based workload model designed to function primarily as a decision support tool to monitor pathologist staffing levels. We devised a high-level proof-of-principle approach to determine whether it is possible to apply AABACUS as a decision support tool for quality improvement through analysis of alternative laboratory workflows that have potential to impact C-TAT. Our use of AABACUS in this proof-of-principle quality improvement endeavour was two-fold: (1) we leveraged the ability of AABACUS to link data at the slide level to data at the case level, which enabled the automated calculation of C-TAT; and (2) we adapted AABACUS to evaluate the impact of laboratory workflow activities (specifically workflow bifurcation activities) on the calculated C-TATs. We have coined the term 'L-AABACUS' to describe the adaptation of AABACUS to the analysis of laboratory workflow.

  • immunohistochemistry
  • quality improvement
  • workflow
  • management

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  • Handling editor Runjan Chetty.

  • Contributors SK and CCC both made substantial contributions to the conception, design of the work, analysis and interpretation of data, drafting the work and revising it critically for important intellectual content, provided final approval of the version published, and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Commissioned; internally peer reviewed.