Quality Error Rates in Point-of-Care Testing

Abstract

BACKGROUND Although a theoretical consideration suggests that point-of-care testing (POCT) might be uniquely vulnerable to error, little information is available on the quality error rate associated with POCT. Such information would help inform risk/benefit analyses when one considers the introduction of POCT. METHODS This study included 1 nonacute and 2 acute hospital sites. The 2 acute sites each had a 24-h central laboratory service. POCT was used for a range of tests, including blood gas/electrolytes, urine pregnancy testing, hemoglobin A1c (Hb A1c), blood glucose, blood ketones, screening for drugs of abuse, and urine dipstick testing. An established Quality Query reporting system was in place to log and investigate all quality errors associated with POCT. We reviewed reports logged over a 14-month period. RESULTS Over the reporting period, 225 Quality Query reports were logged against a total of 407 704 POCT tests. Almost two-thirds of reports were logged by clinical users, and the remainder by laboratory staff. The quality error rate ranged from 0% for blood ketone testing to 0.65% for Hb A1c testing. Two-thirds of quality errors occurred in the analytical phase of the testing process. These errors were all assessed as having no or minimal adverse impact on patient outcomes; however, the potential adverse impact was graded higher. CONCLUSIONS The quality error rate for POCT is variable and may be considerably higher than that reported previously for central laboratory testing.

Pre-operative pregnancy testing (POPT) and the undiagnosed pregnancy rate in an elective gynaecology surgery population

“…Point of care urinary pregnancy testing references are included but are not the focus of this report [14][15][16][17][18].…”

Improving quality in the preanalytical phase through innovation, on behalf of the European Federation for Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for Preanalytical Phase (WG-PRE)

“…Although analytical issues are very frequent, preanalytical errors account for up to 32% of POC errors. This may be underestimated, as preanalytical errors may go undetected due to lack of user knowledge and limited systems for identifying errors [50].…”

Central Laboratory Service and Point-of-Care Testing in Germany—From Conflicting Notions to Complementary Understandings

“…In 1 study, only 225 errors occurred in 407,704 (0.00055%) POCT applications. 49 Another large study reported however, that 205 of 5154 (4.0%) tests could not be conducted with POCT devices and had to be transferred to the central laboratory. 50 Reported overall error frequencies for central laboratories range from 0.006% to 0.00012% of results.…”

“…One study found that only 32% of all errors are in this phase. 49 Automation, standardization, internal and external quality controls as well as better trained personnel has led to a dramatic reduction in analytical errors in the central laboratory. 47 It accounts for only 7% to 13.3% of the total error.…”

“…Therefore, operator incompetence is one of the leading sources of errors. 55 For example, users were unable to authenticate themselves, minor maintenance procedures could not be performed, 49 and manufacturers' instructions were disregarded. 56 Overall, 65.3% of POCT errors fall to the analytic phase.…”