There are many logistical and operational considerations to take into account when setting up a clinical trial, longitudinal study, in vivo animal study, or any other study approach that will involve the collection of biospecimens. This two-part blog series will focus on helping you simplify your specimen management issues and keep sample-related costs low, from the perspective of the biorepository staff. Consider it a “lessons learned” from previous experiences…
1. Always print (never hand-write) all information on the vial label.
Hand-written labels still happen! However, no matter how legible the writing, all kinds of unnecessary risk factors are brought into play: different countries may have slightly different approaches to how alphanumeric characters are written, and certain characters may be difficult to interpret (Is it a “G” or a “6”? Is it an “O” or a “0”? Is it a capital I, lower-case l, or a 1?) If condensation on the vial causes the writing to smear, the problem is compounded. Repository staff will always do their best to enter the correct information into the Inventory Management System (IMS), but any of the above factors can lead to transcription and entry errors and downstream delays in reconciling and retrieving these samples.
You will save yourself many headaches by using a thermal transfer label printer with the appropriate label and ribbon stock (see #2 for more details).
2. Use label stock that will handle the storage temperature
Cost/budget is a primary concern when developing a study, but skimping on label stock is not cost-effective. Stationery labels are great for labeling envelopes, but are most definitely not appropriate for labeling biospecimen vials, as they are easily damaged by condensation and may not remain adherent at extreme storage conditions temperatures.
When selecting the appropriate label stock, a multitude of options are available. Some things to consider during the selection process:
- What is the anticipated final storage temperature? Will the selected label stock remain adherent at that temperature?
- Is the ribbon stock (ink) resistant to any organics (ethanol, formalin, acetone) that the samples may came in contact with? You don’t want the printed information to rub off or erode.
- Will samples be re-labeled while frozen? Standard cryolabels applied at room temperature will bond properly and adhere after they are frozen. However, condensation and temperature often interfere with bonding when labels are applied to frozen vials. In this case, special label stock should be kept on hand.
3. More information—barcode and eye-readable—on labels is better.
Including enough information on the vial to allow for accuracy in inventory and quality inspection activities is crucial. Any activities involving biospecimens typically include, at the minimum, the specimen ID number, and this should be a prominent aspect of the label layout.
Providing the ID in a barcoded format increases efficiency and accuracy in inventory management and reduces the potential for data entry errors. When possible, use common linear/1D (such as Code 128 or Code 39) or 2D barcodes. While an in-house or proprietary IMS may be configured to work with certain non-standard symbologies, the use of such barcoding may create scanning issues for downstream investigators.
In addition to a barcode, an eye-readable version of the ID is highly recommended. Staff accessing specimens may not have ready access to a barcode scanner (and repositories are not yet staffed with Terminators/cyborgs sporting retinal scanners). A printed ID will allow identification of a sample without a trip to the workstation.
Finally, collaborate with your biorepository provider during the planning stages of the study, to ensure that the data and barcodes on the label are compatible with study and sample management objectives.
4. Avoid replication of specimen IDs when possible.
It makes sense that if a sample is divided into multiple aliquots, all the aliquots can be treated equally. One aliquot is as good as another. Why bother with a unique ID? However, much like the saying “Nature abhors a vacuum” (although the scientific merits of this statement have long been debated1-3), many inventory systems abhor replicated IDs—or, at the very least, the repository staff using the systems abhor duplicate IDs. Many, if not all, IMS require uniqueness; even those configured to allow replicated IDs still use an underlying data element that makes each sample unique (e.g., a system-generated stock number).
Consider how replication of IDs can affect the process of specimen retrieval: a study site collects urine from a participant at Visit #3 (PID 12345) and creates and ships four aliquots to a biorepository. Since all four aliquots are viewed as being the same (from an analytical standpoint), each vial is labeled “12345V3U” and put into inventory. Three years later, a request for shipment is received, including only the specimen ID. When the repository attempts to upload the request for “12345V3U” into the IMS, the system throws an error; it cannot determine which of the four aliquots is being requested. The technician then needs to manually override the system and/or create a new request using a unique data. If the entire study is designed in such a manner, a simple request for 100 samples can result in significant manual intervention, dramatically reducing efficiency.
To alleviate the potential for such a scenario, consider adding a unique suffix to each aliquot generated (e.g. “12345V3U1”, “12345V3U2”, etc. or “12345V3-U1”, “12345V3-U2”, etc.) and work with the biorepository to establish the most efficient method for requesting samples to be pulled/shipped. For example, in addition to supplying the specimen ID, include the stock number, sample ID, or some other unique identifier (which should be available in a standard inventory report) as part of the request.
Stay tuned for Part II of this blog post that will identify additional items to consider when establishing a biospecimen collection. In the meantime, if you'd like to learn more about planning sample collection and ways to help make the process as cost-effective as possible, download our eBook Standardizing Biosample Management: Why Use Collection Kits?