Prospective, observational study comparing automated and visual point-of-care urinalysis in general practice

Abstract

ObjectivePoint-of-care testing (POCT) urinalysis might reduce errors in (subjective) reading, registration and communication of test results, and might also improve diagnostic outcome and optimise patient management. Evidence is lacking. In the present study, we have studied the analytical performance of automated urinalysis and visual urinalysis compared with a reference standard in routine general practice.SettingThe study was performed in six general practitioner (GP) group practices in the Netherlands. Automated urinalysis was compared with visual urinalysis in these practices. Reference testing was performed in a primary care laboratory (Saltro, Utrecht, The Netherlands).Primary and secondary outcome measuresAnalytical performance of automated and visual urinalysis compared with the reference laboratory method was the primary outcome measure, analysed by calculating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) and Cohen's κ coefficient for agreement. Secondary outcome measure was the user-friendliness of the POCT analyser.ResultsAutomated urinalysis by experienced and routinely trained practice assistants in general practice performs as good as visual urinalysis for nitrite, leucocytes and erythrocytes. Agreement for nitrite is high for automated and visual urinalysis. κ's are 0.824 and 0.803 (ranked as very good and good, respectively). Agreement with the central laboratory reference standard for automated and visual urinalysis for leucocytes is rather poor (0.256 for POCT and 0.197 for visual, respectively, ranked as fair and poor). κ's for erythrocytes are higher: 0.517 (automated) and 0.416 (visual), both ranked as moderate. The Urisys 1100 analyser was easy to use and considered to be not prone to flaws.ConclusionsAutomated urinalysis performed as good as traditional visual urinalysis on reading of nitrite, leucocytes and erythrocytes in routine general practice. Implementation of automated urinalysis in general practice is justified as automation is expected to reduce human errors in patient identification and transcribing of results.

Urine dipstick precision with standard visual and automated methods within a small animal teaching hospital

“…In human clinical practice, it has been shown that when compared with visual reading, automated POC analysis of urine dipsticks may be associated with higher sensitivity, higher reproducibility and higher agreement with a laboratory reference method, being also userfriendly. [18][19][20] Consequently, the automated method is currently recommended 21 and several human medical institutions routinely employ it. 22 23 However, these human medical studies were limited in scope (one parameter investigated), 18 number and experience of subjects, 19 20 as well as utilising diferent strips for visual and automated methods.…”

Evaluation of the Clinitek®, a point-of-care urinalysis system for the measurement of clinically significant urinary metabolites and detection of haematuria in Schistosoma haematobium infected children in southern Côte d’Ivoire

“…We found that the visual read-out and the CLINITEK device had very good agreement for the measurement of haematuria (κ = 0.83) as well as for nitrites (κ = 0.88), a biomarker for urinary tract infections [27]. It also had good agreement for leukocytes, which somewhat reflects a previous finding in routine hospital tests, where agreement between visual and automated read-outs (using another analyser) was very good for nitrites and good for haematuria albeit poor for leukocytes [17]. The agreement was, however, only fair to moderate for all other biomarkers.…”

“…Point-of-care testing requiring little equipment and minimal training can improve healthcare globally, in particular in settings where high quality medical care is a challenge [22]. Many studies have compared performance of visual read-out vs automated read outs (using CLINITEK or other devices), where they tended to demonstrate on-par or superior performance of the analyser as compared to visual read-out [17, 23]. However, they were largely evaluated in controlled laboratory or hospital settings [24, 25], and usually focused on a single parameter to about three parameters [15, 26].…”

“…All the parameters can be read out visually; however, the consistency of the read-outs may vary between individuals. In clinical settings, an automatic urinalysis reader is typically used as it eliminates bias due to subjective reading by naked eye and increases the throughput of read-outs (each read only requires one minute to process) [17]. Portable, battery-operated versions of these devices have been introduced which would, in theory, render them usable in more remote areas [6, 18].…”

Optimizing the u411 automated urinalysis instrument for veterinary use

“…The Cobas u411 Analyzer (Roche Diagnostics) is an automated, reflectance photometry‐based dipstick urinalysis instrument designed for use with Roche's CHEMSTRIP 10UA technology. The advantages of automated urinalysis established in human medicine include decreased operator time, decreased turn‐around time (if the automated results are connected to the laboratory information management system or LIMS), increased precision (decreased intra‐ and interobserver error), elimination of transcription error to the LIMS, and the potential for improved accuracy . Increased accuracy is particularly important for some analytes, such as pH, which are known to suffer from poor diagnostic accuracy using dipstick urinalysis techniques …”