Background: Currently, the Anatomical Pathology unit at Saint Paul's hospital in British Columbia, Canada accepts all specimens sent to them from any department or physician's office. Naturally, some specimens that enter the system at Saint Paul's hospital do not have any added diagnostic value and constitute diagnostic service waste.

Aims: The aim of this project was to retrospectively identify waste specimens so that they can be removed from the system in the future, halting the practice of indiscriminate pathology investigations and reducing costs while improving the department's efficiency.

Methods: Using the hospital's Laboratory Information System, a list of 407,407 records examined by pathologists in 2019 was created. The list was further refined, yielding 34,872 unique accessioned cases in 2019. The specimens that did not fit the definitions of waste as according to the Glossary for Specimens Not Required for Submission to Pathology were removed, which refined the data set to 1,650 potential cases of diagnostic waste. The list was further refined by Dr. Myles who analysed the data set, reducing the list to 1,214 preliminary cases that could be classified as waste. The pathology reports for these cases were then examined by Dr. Myles who retrospectively identified the specimens that yielded no diagnostic value.

Results & Conclusions: Out of all 1,214 cases examined, 55 we are flagged as potentially diagnostic as they indeed needed pathologist analysis and only one case brought forward new diagnostic information. The final list of waste specimens resulted in a diagnostic waste prevalence of 0.03 (1,159 / 34,872 unique accessioned cases). Therefore in 2019, 3% of all the cases seen by pathologists at Saint Paul's hospital did not yield any diagnostic value and could be classified as wasteful.