Combing Through Samples to Eliminate Knots

Here at WRI, we have a growing inventory of Clinical Breast Care Project (CBCP) blood and tissue samples totaling 80,000 aliquots.  We have been collecting and storing samples since 2001.  Every sample donated is a valuable asset for our biomedical research activities.  We manage our inventory using quality standards so that we can provide high quality specimens to our research scientists.  Therefore our aim is to reduce errors to the barest minimum (as is humanly possible).   

To ensure these goals are met, we perform regular Sample Quality Assurance (SQA). One of our SQA was performed on CBCP samples collected prior to December 2007.  We predicted there would be some errors made in the early days of sample collection especially since we have modified our Standard Operating Procedures (SOP) over the years.  This SQA was the first that represented a time frame of this magnitude.

The project was initiated in August 2010 and completed in December 2011.  Boxes were physically pulled from the freezers and compared to sample records in our electronic databases.  It was not practical to check every individual sample so we formulated a plan to check 20% of blood samples per box and 100% of tissue samples per box.  Sample discrepancies were corrected and logged onto our Quality Assurance tracking database.  Paper and electronic records were kept during the SQA project to monitor progress and keep track of corrections.

The SQA project allowed us to check 19.7% of our total CBCP inventory.  We observed an error rate of 2.5%.The most common errors were from hand written information on sample tubes. We observed during this SQA exercise that errors were more common during the earlier years when we did not utilize a bar coding system. 

 We have since implemented a bar-coding system which has decreased data entry time and errors.  We also continually update and improve our SOP’s for sample collection, processing, and storage.  All inventory errors have so far been corrected.