|Year : 2014 | Volume
| Issue : 2 | Page : 96-102
Self assessment of pre, intra and post analytical errors of urine analysis in Clinical Chemistry Laboratory of Alexandria Main University Hospital
Ola Sharaki, Abla Abouzeid, Nermine Hossam, Yasmine Elsherif
Department of Clinical and Chemical Pathology, Alexandria University, Egypt
|Date of Web Publication||20-Jun-2014|
Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University
Source of Support: None, Conflict of Interest: None
Background: Analysis performed in the laboratory is subjected to variance; hence, every clinical laboratory must have adequate procedures to assure quality of the medical results reported. The definition of a total testing process incorporates the three classical phases of performance in laboratory testing: (1) pre analytical, (2) analytical, and (3) post analytical. Each phase when carried out properly plays an important role in preventing laboratory errors. Aim of the Work: The present study aimed at evaluating the performance of the Clinical Chemistry Unit of Alexandria Main University Hospital regarding urinalysis, through identification of the problems related to the total testing process. Materials and Methods: The study was conducted on 514 consecutive urine specimens that were received at the clinical chemistry laboratory of Alexandria Main University Hospital, during 3 months period from March to June, 2013. Inspection sheets were based upon the integration of the CLSI approved guidelines for urinalysis collection, transportation and preservation, inspection checklist of the CAP, and the review of the literature for similar studies. Results: Regarding the 514 studied request forms for urine analysis, they were found missing some data essential for interpretation of patient test results as recording time of specimen collection and time the specimen received by the lab (11.85%), followed by 462 missing requests and preliminary diagnosis or relevant clinical information (380 requests), which accounted for11.02 and 9.06% errors respectively. The request form was missing other important data as patients' identification, in 29 requests (0.69%), sex in 239 requests (5.7%), age in 208 requests (4.96%), date of specimen collection in 178 (4.24%), tests requested in 30 (0.72%), and authorized physicians' signature in 185 (4.41%). As regards request forms being authorized by a physicians' name or signature, our study showed that almost one third (185) of the request forms of the studied samples, lacked any indication for ordering physician, which accounts for 4.41% of the TTP errors. Also a comparative study was done between the pre analytical errors in the authorized request form and the unauthorized forms, which revealed that there was a high statistical significance difference (P < 0.0001) between the two forms, with errors being much lower in the authorized request forms. In this study the analytical phase showed the least number of errors, 23 errors done in 1970 activities for 514 specimens studied and 0.55% TTP errors. The high frequency in the analytical phase was for error of analysis 0.31% (13 specimens), followed by 6 specimens lost (0.14%), and 4 specimens mixed up (0.10%) out of 514 specimens study sample. Post analytical phase ranks the second in the error frequency in the present study, 487 errors in 1461 activities done for 514 specimens, which account for 11.61% of the TTP errors. As regards studying the post analytical phase, there was no results loss, but also there was no result verification procedure nor age and sex reference ranges in the results report.
Keywords: Quality, total testing process, urine analysis
|How to cite this article:|
Sharaki O, Abouzeid A, Hossam N, Elsherif Y. Self assessment of pre, intra and post analytical errors of urine analysis in Clinical Chemistry Laboratory of Alexandria Main University Hospital. Saudi J Health Sci 2014;3:96-102
|How to cite this URL:|
Sharaki O, Abouzeid A, Hossam N, Elsherif Y. Self assessment of pre, intra and post analytical errors of urine analysis in Clinical Chemistry Laboratory of Alexandria Main University Hospital. Saudi J Health Sci [serial online] 2014 [cited 2021 Jul 24];3:96-102. Available from: https://www.saudijhealthsci.org/text.asp?2014/3/2/96/134863
| Introduction|| |
Quality is defined as meeting or exceeding a customer's expectations.  Quality Assurance (QA) requires identification of the causes of problems and their elimination through Quality Improvement (QI). ,,
The quality process is crucial for health care leaders to improve outcomes and adapt to change as well as to deliver cost-effective and high-quality patient care.  Regulators, payers and patients continue to demand performance-based data that documents compliance with quality standards and benchmarks. 
In the last few decades laboratories became computerized, old equipments were replaced and modernized, optimized transportation systems, and automating specimens processing. These changes have allowed laboratories to maintain services in the face of an ever-increasing volume of testing from all areas of the health care system. Also during these years, the location of testing has become more distributed, as point-of-care testing devices now allow quality laboratory work to be performed at many care locations. 
The problem of medical errors has recently received a great deal of attention, which will probably increase.  In view of increasing attention focused on patient safety and the need to reduce laboratory errors, in laboratory medicine, it is important that clinical laboratories collect statistics on error occurrence rates over the whole testing cycle, including pre, intra, and post analytical phases. 
Pre-analytical phase means all procedures performed before the sample reaches the laboratory. ,, while the analytical phase is mainly concerned with actual laboratory performance and analysis. The post analytical procedures within the laboratory include verifying laboratory results, feeding them into the laboratory information system and communicating them to the clinicians. 
Urine has a long history as a specimen for analysis in clinical laboratories. After blood, urine is the most commonly used specimen for diagnostic testing, monitoring of disease status and detection of drugs. Urine testing using both automated and traditional manual methods is growing rapidly. ,,
Poor core laboratory performance that causes delays in diagnosis and treatment is an impediment to optimal patient care, particularly in high volume patient care areas such as Alexandria Main University Hospital. Thus; laboratory errors under the control of both the laboratory and other health care units should be the focus of quality improvement initiatives.
The aim of the present work was to evaluate the current situation of the clinical chemistry laboratory of Alexandria Main University Hospital as regards urinalysis. This was done through identification of the problems related to pre, intra, and post analytical phases for urinalysis in the clinical chemistry unit, by using different inspection sheets that help in the assessment and evaluation of the quality of performance and their comparison with the international guidelines for urinalysis.
| MATERIALs AND METHODS|| |
Several organizations have developed and implemented quality initiatives to ensure that clinical laboratories incorporate the principles of quality management and assurance in their daily operations. The standards and guidelines of these organizations , are the material for the inspection sheets used in this study to help assess the performance and detect pre, intra and post analytical errors as regards urinalysis in the clinical chemistry unit, of the Clinical Pathology Department, Alexandria Main University Hospital- Egypt.
The study was conducted on five hundred and fourteen (514) consecutive urine specimens that were received at the clinical chemistry laboratory of Alexandria Main University Hospital, during the period of 3 months, March to June, 2013.
Inspection sheets have been formulated to help in the assessment of the performance of the clinical chemistry unit services, in the Clinical Pathology Department, Alexandria Main University Hospital; this assessment included pre-analytical, analytical and post analytical phases as regards urinalysis. Inspection sheets were based upon the integration of the Clinical and Laboratory Standards Institute (CLSI) approved guidelines for urinalysis collection, transportation, and preservation,  "1994 inspection checklist of College of American Pathologists" (CAP); renewed and revised at 2009,  and the review of the literature for similar studies.
Checklists included series of questions, which are closed-type questions designed to produce either a 'Pass' response (as no error detected), or a 'Error' (error detected). Questions that cannot be answered by either are considered not applicable 'NA'.
These checklists evaluate the following items
Checklist I: Urinalysis Total Testing Process Checklist.
Checklist I questions were classified into three groups; each group contained a number of questions concerning one of the pre-analytical, analytical, and post analytical activities for urinalysis error detection.
Checklist II: Urinalysis Detailed Analytical Phase Checklist, which entails more details of the analytical phase.
Checklist II items were formulated for the evaluation of the analytical phase as regards physical, chemical, and microscopic examination of the urine specimen to assess errors of analysis.
After assessment of pre analytical, analytical, and post analytical activities, using the checklists prepared, data collected through the inspection sheets was recorded and statistically analyzed using SPSS software version 17.0. Data was presented as percentages. Groups were compared by Chi-square test, or Fisher's exact test. All reported "P" values are two-tailed and the level of significance was set at 0.05.  Results obtained were interpreted and implemented with the suitable corrective and preventive actions to upgrade the performance in urinalysis testing process in the clinical chemistry unit.
| Results|| |
Results of the present study were presented as follows:
- Error frequency and Overall percent of errors in the pre analytical, analytical, and post analytical phases [Table 1] and [Table 2]
- Distribution of errors in the pre analytical phase in relation to authorization [Table 3]
- The distribution of the study sample according to errors of analysis in the analytical phase [Table 4]
- Distribution of errors in the post analytical phase according to the TAT [Table 5].
|Table 1: Errors frequency in the pre analytical, analytical, and post analytical phases|
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|Table 3: Pre-analytical errors in the test request in relation to authorization|
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|Table 4: The distribution of the study sample according to errors of analysis in the analytical phase|
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|Table 5: The distribution of the study sample according to reasonable turnaround time|
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Error frequency in the preanalytical, analytical, and postanalytical phases
[Table 2] showed the overall percent of errors in the three analytical phases. With a total error frequency of 4194.There was a statistically significant difference (Chi-square, 1268; df, 2; P < 0.0001) in the error frequencies observed in the three investigated phases where, the highest number of errors was found in the pre-analytical phase with 3684 error (87.84% of total error), followed by post-analytical phase errors = 487 (11.61% of total error) and 23 analytical error (0.55% of total error). Also the error frequency in the pre- analytical phase was significantly higher than the error frequency in the post-analytical phase, with elimination of the analytical phase. (Chi-square, 54.67; df, 1; odds ratio, 1.554; 95% CI, 1.382- 1.747; P < 0.0001).
[Table 3] showed the pre analytical errors in the test request in relation to authorization. Tests' requests that are signed by authorized personnel showed less number of errors with high statistical significance (P = 0.000) as regards recording; patients' identification, patients' sex, patients' age, date of specimen collection, tests requested, and recording patients' preliminary diagnosis, or relevant clinical information in the tests' request form.
[Table 4] showed errors of analysis. Where analytical errors were detected during analysis of 13 specimens (2.53%) from the total 514 studied samples.
[Table 5] showed the distribution of the study sample according to specimen being analyzed in reasonable turnaround time (TAT). From time of receiving of specimen at the lab to time of results delivery; all of the specimens were analyzed in reasonable TAT (4-8 hours).
| Discussion|| |
Pre-analytical mistakes are a major source of error in the total testing process (TTP); they had been considered as one of the most important quality indicators. Pre-analytical mistakes may include physician's order missed, patient identification error, specimen collected in insufficient quantity, inappropriate container used, inappropriate quality of specimen, specimen lost in transi. ,
The present study showed that the error frequency was 87.4% in the preanalytical phase, 0.55 and 11.61% for the analytical and postanalytical phases, respectively, with high statistical significance difference (P = 0.000). The pre-analytical phase was found the most defective throughout the total testing process, 3684 error (43.7%) in 8426 activity done for 514 urine specimen, representing 87.84% percent of the TTP errors [Table 1] and [Table 2].
Similar results were reported showing that the distribution of preanalytical errors, in a study carried out in Thailand, was 84.52%.  Other investigators showed that 71% of a healthcare organization's incidents were classified as pre-analytical problems.  It was also shown that pre-analytic errors accounted for 86% of the whole laboratory mistakes in the study done by Crim J et al. 
Similarly to a study was done in the United States to assess the quality of laboratory testing proved that 45% of lab errors occur in the pre-analytic processes, 10% for analytic errors, and 45% for post-analytic errors. 
Laboratory errors may lead at best to, a sample recollection to repeat the analysis, inconvenie to the patient, delaying treatment and increasing the cost. At worst, a doctor may act on incorrect results and the patient may be treated inappropriately. As a consequence of this distribution of errors, laboratories are urged to focus their attention on pre-analytic and post-analytic processes to improve patient safety. 
Our survey detected several defects in the pre-analytical phase such as the request form used, sample collection, criteria for acceptance and rejection of primary samples and monitoring the transportation of samples to the laboratory.
Laboratory request forms provide information about the laboratory test being requested for. They contain demographic data such as name (s), date of birth, subject's address, age, and sex. Other details include the ward, laboratory number, doctor's name, signature of the doctor, telephone or fax number of the doctor, clinical details, fasting status of the subject and the date of request. Omission of information on the forms may lead to laboratory errors.  Similarly results of a research carried out in South Africa, it was observed that laboratories were experiencing significant problems with incompletely filled request forms and the standard of completion of request forms was poor and represented a threat to patient safety and quality of laboratory services. 
The major pre-analytical errors of concern noticed in a study done in Nigeria were that the treating physician's names were missing in 13.1% of the forms and their signatures were missing in nearly 13.4% of the lab forms. Clinical information was illegible in 89.25% of the forms. The diagnosis was not mentioned in 61.2% of the lab request forms and the information pertaining to the type of specimen was missing in 61.6% forms. 
Another study was conducted to evaluate the level of completion of laboratory request forms at the hematology department of a Ghanaian tertiary hospital. It demonstrates that, the standard of completion of request forms was poor. Essential information required on the forms was often missing. This can lead to limited advice given by laboratory physicians and may increase the potential for errors. Conversely, provision of all the information needed on the forms will aid laboratory diagnosis and enhance patient care and save time and resources. There should be closer interaction between clinicians and laboratory personnel to improve quality of services. 
A similar study reported that the information regarding medication (s) used by the patient (89.6%) and doctor's contact number (61.2%) were the most incomplete parameters. No diagnosis was provided on 19.1% of forms, and incomplete ward information was found on 4.9% of forms. As laboratory data influences 70% of medical diagnoses, incorrect or incomplete data provided to the laboratory could significantly impact the success and cost of overall treatment. 
Another retrospective study conducted at the department of chemical pathology in a teaching hospital in Nigeria; Showed that the only well documented parameter was the patient's name. Time and date of specimen collection was recorded in 10.3% and 36.5% of forms respectively. Those who had their date of birth recorded were 86.4%. The working diagnosis was recorded in 93.2%. There was no information on medication on the entire patients. Fully written diagnoses occur only in 92.2% of forms. As laboratory data plays a significant role in medical diagnosis, incorrect or incomplete data provided to the laboratory could significantly have impact on the comments and successful outcome of treatment that patient receives. 
As regards request forms being authorized by a physicians' name or a signature, the present study showed that almost one third (185) of the request forms of the studied sample, lacked any indication for the treating or test ordering physician, accounting for 4.41% percent of the TTP errors [Table 3]. Also a comparative study was done between the pre-analytical errors in the authorized request form and the unauthorized forms, which revealed that there was a high statistical significance difference (P = 0.000) between the two forms, with errors being much lower in the authorized request forms, in recording of the following items; patients' identification, sex, age, date of specimen collection, tests requested, and patients' clinical information.
As a last resort patient's samples accompanied by incompletely filled request forms should be rejected since it may lead to inappropriate diagnosis.
Preanalytical phase also showed defects other than the request form, as not obtaining the right specimen for the test, 60 specimen (1.43%), not using the proper container for the indicated specimen, 225 container (5.36%), missing the patients' identification on the container, 191 container (4.55%), inappropriate specimen amount collected, 60 specimen (1.43%), losing 17 test request (0.41%).
It is recommended that urine specimen should be analyzed within 1-2 hours after collection,  while our study showed that 47 specimens (1.12% percent of the TTP errors) of the studied sample were not analyzed in appropriate time, i.e. analyzed after 2 hours of collection. Centrifugation of urine specimens is recommended for approximately 5 min at 400 RCF;  In the present study improper specimen centrifugation (5000 RPM for 2 min) was done to almost 1/3 of the specimens (379), accounting for 9.04% percent of the TTP errors.
Our results were in agreement with a number of studies who reported that; pre-analytical mistakes (missed or incorrectly interpreted laboratory orders, improper patient preparation, incorrect patient identification, wrong specimen container, and mislabeled or mishandled specimens) accounted for good portions of TTP errors accounting for 46% of the total laboratory errors, in a tertiary care hospital. 
Lippii G reported that lack of standardized protocol for sample collection, including patient preparation, specimen acquisition, handling and storage, account for up to 93% of the errors currently encountered within the entire diagnostic process. 
Pre-analytical phase is largely performed outside the clinical laboratories; it is not under the control of laboratory management, physicians and nurses may have a role in the pre-analytical mistakes. , This indicates that the active monitoring and feedback control of all potential defects generated by non laboratory personnel are essential to enable the inclusion of steps outside the laboratory within the laboratory quality assurance plan. 
Monitoring of sample transport to the laboratory is still defective. Specimen tracking system is now in process to ensure that all specimens are actually received. Laboratory management should implement an adequate process for correcting problems identified in specimen transportation, and improving performance of clients that frequently submit specimens improperly. 
The analytical error rate has improved significantly over time due to the wide use of automation and by the correct adoption of rules for defining the allowable errors in internal quality-control practice. 
The analytical phase of the testing process is the most easily controllable and standardized phase throughout the whole testing process. Any quality assurance plan starts with the selection and evaluation of a suitable method. The next step is the development of quality control procedures to maintain precision, then confirming accuracy by participation in a proficiency testing program.
We had chosen the most important components of the analytical phase to be evaluated, which include losing a specimen, mixing up, equipment failure, and errors of analysis (examination).
In our study the analytical phase showed the least number of errors, 23 errors done in 1970 activity for 514 specimens studied, with over all error frequency 0.55% [Table 1] and [Table 2].
Similar study conducted in 14 pathology laboratories in five Australian States, to measure transcription and analytical errors made by Australian chemical pathology laboratories revealed that pathology laboratories had a transcription error rate of up to 39% and an error rate of up to 26% for analytical results. 
Benchmark was established for measuring errors in the laboratory to provide guidance for quality improvement. Among 746 tests reviewed, there were 393 questionable results, 160 confirmed laboratory errors, 46 of which caused inappropriate patient care. Of those 46 errors 24 were analytical errors, i.e. analytical errors were the major cause (52%) of inappropriate patient care. 
In our study the highest error frequency in the analytical phase was for error of analysis 0.31% (13 specimens), followed by 6 specimens lost (0.14%) and 4 specimens mixed up (0.10%) out of 514 specimens study sample. While no equipment failure was detected during the study period.
Medical laboratories today do focus on errors and have many tools and techniques for evaluating, measuring, monitoring, detecting, correcting, and improving quality and concluded that it is more important to focus on pre-analytic and post-analytic errors, rather than analytical errors.  Yet all sources of errors are important and analytical quality is still an issue in medical laboratories today. 
Postanalytical phase is ranked the second in the error frequency in our study and the similar studies, 487 errors in 1461 activity done for 514 specimens, with 11.61% overall percent of errors [Table 1] and [Table 2].
There was no results loss, but also there was no results verification, or age and sex reference ranges in the results report.
A written procedure for results reporting, verification, establishment of the reportable range for each analytic procedure before implementation together with the presence of defined process for correcting reported results, are still lacking. They need collaboration of efforts of laboratory manager and technical staff. In instances information such as age and gender are important in identifying and sorting out both the subject and samples. Also reference ranges for some analytes vary with age and gender. 
Laboratory test TAT (Turn-around Time) is one of the most important performance measures and a reliable indicator of laboratory effectiveness for many clinical laboratory users. ,, The present study revealed that all the valid sample study specimens (487) were analyzed in appropriate time, the mean time of analysis was 3.24 + 0.55 hours, and the minimum time of analysis was 2.05 hours, while the maximum time was 4.45 hours, which matches the CLSI urinalysis guidelines,  which states that TAT for routine samples should be within 4-8 hours. Similar study was undertaken in a hospital in Delhi to evaluate the turnaround times for inpatient, outpatient and emergency samples. TAT was calculated from sample reception to report dispatch. The average TAT for the clinical biochemistry samples was 5.5 h for routine inpatient samples while the TAT for the outpatient samples was 24 h. 
Clinical Pathology Department of Alexandria Main University Hospital is seeking for quality improvement throughout the whole testing process, ISO accreditation was earned on 5/2013. Therefore it is important for the department to evaluate the performance of each unit and document in details every procedure performed in the laboratory before being assessed by an external audit. A study of the development of a strategy to enhance quality throughout the total testing process started with systematic analysis of specimen workflow, continued with education and thorough monitoring via error tracking systems, and ended with the elimination or redesign of deficient procedures.
A limitation of this study was our inability to assess the effect, if any, that this poor rate of completion had on patient's management. This is a possible area for future research.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]