A study that was published in 2002 concluded that the majority of laboratory errors occur in the preanalytical phase of testing.6
Steps in the preanalytical phase occur both inside and outside the laboratory and are performed by both laboratory and non-laboratory personnel. While the following list is not exhaustive, some of the most common sources of error in the preanalytical phase include:
- Patient preparation
- Patient not told to be fasting
- Improper or no instruction to the patient on proper collection of specimens such as clean catch urine
- Patient injured during phlebotomy
- Development of hematoma
- Nerve or tissue damage caused by improper technique or wrong-site venipuncture
- Requisition errors
- Patient information missing, illegible, or on the wrong patient
- Wrong tests ordered
- Patient identification
- Patient incorrectly identified
- Specimen not labeled or incorrectly labeled
- Specimen integrity
- Not enough specimen for testing
- Visible hemolysis
- Inadequate cleansing of venipuncture site resulting in contamination during blood culture collection
- Specimen centrifuged too long or not long enough
- Specimen placed in improper preservative
- Specimen transported at the wrong temperature (eg, specimen that should be placed on ice immediately after collection is transported at ambient temperature)
- Shipment of specimen
- Shipped at ambient temperature when it should have been shipped frozen
- Delay in shipment
- Order entry
- Incorrect data entered during manual entry of a test requisition
