Though it is known that point-of-care (POC) urine drug screening (UDS) has its limitations, clinicians request POC UDS due to its convenience and cost effectiveness. Common clinical recommendations are to use urine drug screens as the first line of testing followed up by a definitive laboratory test. However, the cost of sending every urine drug test to the lab is not always realistic or feasible for some clinical settings or patient populations. There needs to be a balance between cost and the best solution to meet the needs of the patient population. Instead of describing optimal drug screening from a scientific perspective, this article presents a real-world case study evaluating the causes that prevented successful implementation of a POC UDS process at a facility initially and then describes the recent, successful implementation of a new POC UDS at the same facility.
The initial implementation examined in this case study was at a substance abuse rehabilitation clinic. The decision to use Kit A was made by the POCT team without considering the perspective of the nurses who would be performing the tests. Important feedback from nursing staff during training was that interpretation of the test results was difficult because the diagnostic lines were difficult to read due to an unclear background on the test strips. Instead of acting on this feedback, the implementing team decided that the quality of the test was adequate to overcome the negative impressions of the operators. However, there was continuous negative feedback from the nurse testers and overall dissatisfaction with the product. After only two weeks of usage, the facility lost confidence in the results and pulled Kit A from its test menu.
New approval process
After some time, the facility again approached the POCT team about possible POC UDS options. Due to the nature of the substance abuse rehabilitation program, it is beneficial for providers to go over the test results with the patients during their office visits. Presenting these test results serves as a conversation starter and facilitates monitoring of the patients' condition and progress.
Based on lessons learned, the POCT team decided on a new process for approval and implementation of POC UDS. The new process included a special meeting between the laboratorians and clinicians. In the meeting, laboratorians gained a better understanding of the needs of the clinicians and the specific patient population. Laboratorians were able to address the functions of the test and to ensure clinicians were well informed of the limitations of the test and results.
Like many other facilities that utilize POC UDS, the clinic chose this type of test due to its cost effectiveness. In this clinic, the clinicians are looking for patient treatment compliance by absence of a substance in the screens. The cost of sending all urine drug screens to the laboratory for confirmatory testing is cost prohibitive and not sustainable for the patient population. At this facility, each patient meets with clinicians three times a week and are tested for presence of drugs every week for eight weeks. For patients to remain in this substance abuse rehabilitation program, they must receive a negative screen result for the substance. Though implementation of POC tests would come with startup and training costs due to competency requirements, there would still be significant cost savings for the patients by utilizing POC UDS and sending samples for definitive laboratory drug tests for specific drugs only when needed.
Approach to common limitations
Some of the common limitations, such as specificity, cross reactivity, cut-off, and adulterants were discussed with the providers. In practice, the clinic will resolve these issues by sending positive or any discrepant screens to the laboratory for definitive tests. This would minimize false positive results and their impact on patient treatment. This clinic’s goal is to assist and monitor its patient population. Patients with a positive result on a definitive test are moved to a recovery enhancement group where they will receive further assistance. If the patient tested positive again in the next round, he or she will be moved to a 12-step additional recovery program. Since the results are not punitive in this setting, the medical director of the facility does not feel the common limitations of POC testing would prevent successful implementation of this type of testing.
A common concern with POC UDS is that some clinicians do not know how to correctly interpret the drug screen results. It is important for clinicians to be informed and educated prior to receiving request approval. Unlike other test kits, UDS is a reverse read. This is where the presence of a line indicates a negative result. This often creates confusion for interpretation. Though the reverse read is not intuitive to either laboratorians or nursing staff, thorough training and job aids should improve accuracy in reading the test results. To ensure proper training and education, training sessions are to be scheduled and members of the POCT team would train each user directly instead of utilizing the “train the trainers” model.
Demonstration — During the approval process, a demonstration session was held with representatives from two clinics and POCT. The POCT team demonstrated the use of Kit B. Nursing leadership and staff who had used Kit A, observed and asked questions. The purpose of the demonstration was to show nursing staff the improved readability of the kit compared with Kit A. The consensus was that Kit B is easier to read than Kit A due to the larger space between the lines. This demonstration provided an opportunity to see if the kit was intuitive from a nursing perspective, a critical view that was not adequately obtained during rollout of the previous version of the test.
Validation — Though Kit B was validated and approved for another facility under POCT team oversight, a “mini” validation was performed despite the waived status of the test. Ten samples were obtained from the lab, including one negative and nine samples that were positive for a variety of drugs tested. A mixture of concentrations were used to test the detection threshold values. There was a greater concern for false negatives than false positives since the procedure dictates that positive samples should be confirmed by laboratory testing. In addition to this “mini” validation, readability was also tested.
Interface build — This facility already has an existing interface and online test ordering and result process for other tests, but not for Kit B. The interface team created an online order and online results page based on POCT team input. Proper ordering processes for initial screening and definitive laboratory tests were created. Appropriate cut-off values were included in the online result page.
Nursing workflow — In addition to the reporting side, the nursing leadership team was tasked to create a protocol and workflow to detail the steps from initial order, sample collection, resulting, and courier service for definitive tests. Input was gathered from nursing staff on the proposed procedures. Processes were evaluated to ensure all steps were clear to the staff who would be performing the tests.
Courier service — Another detail that must be considered in the overall workflow is the process to transport urine samples to the laboratory for definitive tests. The laboratory was contacted to determine appropriate storage requirements for urine samples. The optimal frequency of courier pick-up was discussed with the providers and a decision made based on the needs of the clinic.
Training — With the approval to implement POC UDS, our POCT team started creating training materials and procedures. All draft training materials were submitted to the facility’s nursing leadership for their review and input before finalizing them. Prior to final implementation of the new test, POCT team members would train all users on site.
If clinicians are well informed and are working with laboratorians to ensure proper test interpretation, POC UDS can be a very useful tool despite its limitations. The process used in this case study was derived from lessons learned from both successful and failed aspects of past POC UDS implementations. The final choice of specific tests cannot be decided based on only the laboratory perspective, which prioritizes technical accuracy over ease of use and clarity of readout for standard test performers. Regardless of the technical accuracy of a test, if it is not intuitive for clinicians and nursing, it can cause frustration and mistrust of the results. Lack of clear understanding and expectations between clinical and laboratory staff can potentially defeat the purpose of the testing regimen, which is to improve overall patient care in an efficient and economically feasible way.