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September 26

4 Solutions to Tackle Your Sample Backlog

Maintaining service levels and turnaround times in a fast-paced quality control laboratory can be a challenge. There are many factors which contribute to the build-up of samples to test:
  • Increase in sample volumes
  • Increase in supply chain demand and expedited turnaround requests
  • Availability of equipment, equipment maintenance and calibration
  • Availability of trained and competent analysts
  • Maintaining regulatory control and compliance
As a laboratory manager, you’re continuously juggling all these factors to meet customer expectations. In this blog, we discuss four solutions to help you tackle your sample backlog.



The most common method used for prioritising batches for testing is on a “first-in, first-out” basis. However, this only works if all turnaround time requests were the same.  How do you prioritise a sample backlog where turnaround times vary from 24 hours to 15 days? In addition, supply chain may be asking for different batches to be prioritised over others so that an order is fulfilled in time.
Place batches with the highest priority at the top of the schedule.  These will include batches with short turnaround times as well as batches that have been prioritised by supply chain.  The batches with longer turnaround times, which may include stability samples, can be towards the bottom of the schedule. Be careful not to continuously prioritise shorter turnaround times over longer turnaround times. Track the number of days remaining to meet the turnaround deadline and use this to help prioritise testing of existing batches when new expedited requests are received.
Top Tip – Communication is key. Most people are understanding of delays as long as there is consistent communication of how the testing is progressing.


Bulk Like with Like

Where you have multiple batches of the same product in the backlog, group these samples together.  Typically, if these batches are the same product, they will require the same testing, and therefore, sample prep can be shared, and the analysts can maximise the number of samples loaded into a HPLC run.  Bulking the same samples together also helps reduce the time for data verification as there is less raw data to review for shared sample prep and one HPLC run.
Top Tip – Remember that although bulking analysis is a good way to work through a backlog, always work within the limits of your solution stability.



If you have the budget, overtime is an option.  It gives your analyst a chance to earn extra money, and more time to tackle the sample backlog.  Overtime doesn’t always need to be on a weekend.  Adding an extra hour or two to each day during the week can also be helpful overtime.
Top Tip – Before an analyst commits to overtime, be sure that they have signed all the relevant forms such as a 48 hour opt out agreement.  Your human resources department can help you with this.  



If your laboratory is continuously in a position where the sample backlog remains high despite all efforts, outsourcing testing is another solution.  You may not want to commit to hiring more analysts because of the variable peaks and troughs in workload.  Therefore, sending batches externally for testing is a great alternative to support your laboratory during busy periods.  There is, however, an up-front requirement to formalise the partnership with your chosen external lab, but typically, the time it takes to complete the audit and transfers will outweigh the benefits of having overflow support. 
Top Tip – If you’re considering the option of outsourcing quality control testing or any other laboratory, download our free guide below on How to Select a Laboratory to Partner with.


how do you select a laboratory to partner with

About the Author

Beccy Bell is the Analytical Services Manager at Broughton Laboratories. Beccy joined Broughton in 2009 as an Analytical Chemist. Her educational background includes a BSc (Hons) in Chemistry with Pharmaceutical and Forensic Science from the University of Bradford.​ During her time as an Analytical Chemist Beccy gained experience testing a wide variety of products for both the human and veterinary pharmaceutical markets, working closely with clients to understand their business needs and how Broughton can help these be achieved. Beccy now heads up the analytical team ensuring client expectations are met and is continuously looking to improve current processes and increase laboratory efficiencies.