Journal:Management of post-analytical processes in the clinical laboratory according to ISO 15189:2012: Considerations about the management of clinical samples, ensuring quality of post-analytical processes and laboratory information management

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Full article title Management of post-analytical processes in the clinical laboratory according to ISO 15189:2012: Considerations about the management of clinical samples, ensuring quality of post-analytical processes and laboratory information management
Journal Advances in Laboratory Medicine
Author(s) Yeste, Mᵃ L.L.; Mas, Antonia R.P.; Muñoz, Leonor G.; Álvarez, Silvia I.; García, Fernando M.; Font, Aurora B.; Gómez, Natalia F.P.; Gancedo, Lorena S.; Álvarez, Ana G.; Andreu, Francisco A.B.; Rodríguez, Mᵃ P.C.; Domínguez, Luisa Á.
Author affiliation(s) CATLAB, Hospital Universitari Son Espases, Hospital de la Santa Creu y Sant Pau, Hospital Universitario Miguel Servet, Germans Trias i Pujols Universitary Hospital, Hospital Universitari de Bellvitge, Hospital Universitario de la Princesa, Institute of Oncologic and Molecular Oncology, Hospital Clínico San Carlos, Hospital Universitario Puerta de Hierro, Laboratory Accreditation Board of the Spanish Society of Laboratory Medicine
Primary contact Email: llopez at catlab dot cat
Year published 2021
Volume and issue 2(3)
Page(s) 373-380
DOI 10.1515/almed-2021-0044 (English); 10.1515/almed-2020-0088 (Spanish)
ISSN 2628-491X
Distribution license Creative Commons Attribution 4.0 International
Website https://www.degruyter.com/document/doi/10.1515/almed-2021-0044/html
Download https://www.degruyter.com/document/doi/10.1515/almed-2021-0044/pdf (PDF)

Abstract

ISO 15189:2012 Medical laboratories — Requirements for quality and competence establishes the requirements for clinical specimen management, ensuring the quality of processes and laboratory information management. ENAC (Entidad Nacional de Acreditación), the sole accreditation authority in Spain, established the requirements for the authorized use of the ISO 15189 accreditation label in reports issued by accredited laboratories. These recommendations are applicable to the lab's post-analytical processes and the professionals involved. The standard requires laboratories to define and document the duration and conditions of specimen retention. Laboratories are also required to design an internal quality control scheme to verify whether post-analytical activities attain the expected standards. Information management requirements are also established, and laboratories are required to design a contingency plan to ensure the communication of laboratory results. Instructions are finally provided about the correct use of the accreditation label in laboratory reports. A range of nations and scientific societies support clinical laboratories being required to obtain accreditation. With ISO 15189 being the most specific standard for demonstrating technical performance, a clear understanding of its requirements is essential for proper implementation.

Keywords: accreditation, clinical laboratory, ISO 15189 standard, laboratory information system, post-analytical

Introduction

Clinical laboratories increasingly devote more efforts to improving their methodological and communication skills to help physicians in the interpretation of test results and improve patient outcomes. This type of quality control is found in UNE EN ISO 15189:2013 Medical laboratories — Requirements for quality and competence (ISO 15189:2012, Corrected version 2014-08-15; hereinafter, the ISO 15189 standard), which addresses the revision, reporting, and release of clinical test results[1], as well as other requirements for post-analytical processes. These requirements also address specimen storage, retention, and disposal; the inclusion of post-analytical processes in laboratory quality assurance and continuous improvement; laboratory information management; and the need for a contingency plan that ensures the communication of test results in any scenario.[2][3] ISO 15189 is based on laboratory best practices and employs the information obtained from the lab's quality management system to generate corrective and improvement actions.

ISO 15189 also establishes a set of requirements for laboratories to implement effective methods for the detection and classification of post-analytical errors and the incorporation of information systems and standard operating procedures (SOPs) aimed at reducing errors.[4] Special emphasis is placed on the communication of results, laboratory information management, and risk management. The standard also requires that a contingency plan is designed.

Additionally, and considering that the use of the ENAC (Entidad Nacional de Acreditación) label in laboratory reports is the way Spanish laboratories demonstrate that they comply with accreditation requirements, it is important all accredited laboratories pay attention to the ENAC document CEA-ENAC-01 Requirements for the use of the ENAC label and reference of certification, which establishes the requirements for ENAC and ISO 15189 accreditation label use.[5] However, these ENAC recommendations do not extend the standard and should be considered complementary information that facilitates its interpretation and implementation. The scope of application is the staff involved in post-analytical processes in the clinical laboratory.

Specimen storage, retention, and disposal

ISO 15189 requires that the laboratory define and document the duration of specimen retention, as well as specimen storage and discard conditions. The standard operating procedure should specify the duration of specimen retention and storage conditions, which will be defined according to the nature and stability of each analyte[6] and the applicable legal requirements (see Figure 1). The duration of specimen storage may be extended by legal requirements associated with some types of studies (e.g., histological analyses, gene testing, pediatric studies).


Fig1 Yeste AdvLabMed2021 2-3.jpg

Figure 1. Sample storage, retention and disposal flowchart

Access to archive specimens must be restricted. Easy specimen traceability and location for retrieval must be ensured (for additional testing, result verification, and/or legal requirement, among others). Therefore, it is recommended that the date and person responsible for specimen retrieval be recorded, which is essential in case it is required by law.

The procedure for disposal of clinical specimens and consumables must be documented by the laboratory. It is laboratory’s responsibility to comply with the laws and regulations in relation to the prevention of occupation hazards, even though waste disposal is performed by an authorized external supplier.

Quality assurance and continuous improvement

As with pre-analytical and analytical procedures, post-analytical procedures must be evaluated and audited to ensure compliance with standards. Auditing is also intended to verify whether the process satisfies user’s needs and requirements. Thus, efforts are necessary to improve the effectiveness of the post-analytical process.

Evaluation of the post-analytical process must include the activities carried out both in the laboratory (post-analytical phase) and out of the laboratory (post-post-analytical phase). A range of studies have demonstrated that most errors occur in the post-post-analytical phase due to the variety of services and number of external professionals involved.[7]

The incidence of errors in the post-analytical process varies significantly, from 18%[8] to 47%[9] of total errors. The most frequent errors include misinterpretation of test results by the laboratory, delayed delivery of reports, loss of reports, and failure to report specimen-related events to the requesting physician. Post-analytical errors may lead to incorrect clinical decisions based on a misinterpretation of test results. Poor decision-making may affect the clinical course, prognosis, and outcome of the patient. These are traditionally called post-post-analytical phase/process errors.[8][9][10] These processes can be improved by enhancing interaction between the professionals involved, where communication and training play a crucial role.[11] Another potential source of errors that is expected to increase in the future is the inability to check test results in the electronic health record (EHR) of the patient due to technical issues.

The laboratory is required to design a quality control plan to verify whether post-analytical activities meet the established standards. This control is primarily based on strategies aimed at detecting errors and establishing quality indicators (see Figure 2).


Fig2 Yeste AdvLabMed2021 2-3.jpg

Figure 2. Characteristics of the post-analytical quality control plan

Quality indicators of post-analytical processes allow for the objective evaluation of the service delivered to ensure the quality of this process based on compliance with quality standards. For a proper evaluation of results, it is essential that communication between laboratory staff and ordering physicians is regular, fluid, and based on a standard protocol. Indicators of the post-analytical process include reference intervals, cut-off points, action points, graphic representation, self-validation, interpretative comments, reflex tests (i.e., tests automatically performed on the basis of an algorithm), or reflective tests (i.e., tests added by a professional considering the clinical context)[12][13], the clinical information required for the correct interpretation of results, reporting of critical values, and effective release of laboratory test results through the laboratory information system (LIS).[14] According to numerous users, the most important indicator of laboratory performance is the time period between a test request and delivery of results (turnaround time), which is especially relevant for patients seen in or admitted to emergency care.

A model of quality indicators was presented at the Consensus Conference held in Padua in 2013, which assigns a priority score to each indicator to help laboratories implement effective interventions to improve performance. A criterion was proposed for the establishment of quality standards to assess laboratory performance.[14] In the 2016 Padua Conference, a review was performed of the results obtained since 2014 to identify the indicators and quality standards that should be established to comply with ISO 15189:2012 requirements through continuous monitoring of critical activities to minimize risks. The established indicators evaluate all post-analytical stages, from result validation to the effective, timely result release. Indicators are expressed as a percentage of errors in each laboratory activity. The way each activity is expressed is essential (number of requests, patients, samples, among others), since it will allow inter-laboratory comparison (benchmarking) or comparison against recommendations of scientific societies and entities. The indicators included in the Padua consensus statement are detailed in Table 1.

Table 1. Indicators included in the Padua Consensus Statement on the post-analytical process, based upon indicators from the International Federation of Clinical Chemistry and Laboratory Medicine Working Group[15]
Activity Description Calculation formula
Turnaround time Number of reports issued not complying with the agreed timeframe with respect to the total number of reports Number of out-of-time reports/total number of reports in a year × 100 (%)
Turnaround time Turnaround time for different analytes (potassium, INR, WBC, troponin I or T) from request receipt to result report Day and time of issue – day and time of entry (day, time (h/min)); Note: “… for non-emergency analysis of serum potassium concentrations.”
Corrected laboratory reports Percentage of reports corrected by the laboratory after delivery with respect to the total number of reports Number of corrected reports in a year/total number of reports in a year × 100 (%)
Critical result notification Critical results reported out of time with respect to the total number of reported results Number of critical results reported out of time in a year/Total number of critical results in a year × 100 (%); Note: “… for all tests with indication of emergency report” and “… for non-emergency analysis of serum potassium concentrations, etc.”
Critical result notification Mean time to critical result notification Mean (time of result notification – time of result release to the ordering physician (min)); Note: “… for all tests with indication of emergency report” and “… for non-emergency analysis of serum potassium concentrations, etc.”

To overcome these problems and build up a picture of total laboratory errors, the Working Group on “Laboratory Errors and Patient Safety” (WG-LEPS) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) implemented in 2008 a project to design a model of quality indicators (MQI), a harmonized method for data collection administered as an External Quality Assurance Program (EQAP) where confidentiality is guaranteed.[15][16]

In edition to this EQAP, the laboratory should also consider taking part in a benchmarking program. Despite the lack of consensus on quality standards, the relevance of joining an EQAP relies on the information these programs provide about compliance with the standards established by each laboratory and allow inter-laboratory comparison. Despite the high number of errors that occur throughout the post-analytical process and the fact that it is a requirement of ISO 15189 (see section 5.6.3 of the standard), EQAPs are not yet fully developed. In recent years, some entities are implementing EQAPs in parallel to benchmarking programs for pre-analytical processes. These programs include the benchmarking program designed by the WG-LEPS of the IFCC, active since 2008, which evaluates the model of indicators designed by the WG-LEPS itself. Although it is infrequent, some benchmarking and RCPA QAP and UK NEQAS programs address the topic of interpretative comments in the field of clinical biochemistry.[7]

Laboratory information management

State-of-the art technologies and the increased amount of data managed at the clinical laboratory have led to the establishment of demanding requirements for a LIS or laboratory information management system (LIMS).[17] to that point, ISO 15189:2012 requires that all laboratories have an information management system that ensures the accessibility, integrity, security, and confidentiality of patient data. It is essential that both computer-based and paper-based information systems are considered, as well as all scenarios where information is received, generated, or reported. Figure 3 summarizes the main ISO 15189:2012 requirements for laboratory information management.


Fig3 Yeste AdvLabMed2021 2-3.jpg

Figure 3. Main laboratory information management requirements

The laboratory must guarantee patient data protection by adopting all measures necessary to prevent any unauthorized access to data (e.g., access to physical facilities and location of computers, using automatic screen lock, embracing cybersecurity). With regard to laboratory reports, all methods of delivery must be considered (e.g., electronic systems, paper, electronic mail, or smartphone) to establish the appropriate security measures (e.g., dissociated information, encryption, etc.).

Additionally:

  • The laboratory should identify the persons who are authorized to access and use laboratory information and establish security levels based on a user’s profile.
  • Security measures must be adopted to protect information and prevent any alteration or destruction of information by unauthorized personnel. Monitoring of electronic systems allows for the detection of potential breaches of security.
  • Measures must be adopted to mitigate the risk of unintended information degradation or loss, whether available on paper or electronically.

The information system must have been validated by the supplier. However, the laboratory has its own responsibilities. For example, it must verify and monitor the correct transfer of unaltered information between the laboratory and other internal (e.g., laboratory analyzers) and external (e.g., hospital information system or HIS) information systems. In some situations, verification is also required, such as after software updating or after a piece of equipment has long been unused. This validation/verification should be documented in a report.

Availability and access to all the information generated must also be ensured. The location of stored information must be clearly identified, and access must be restricted to authorized personnel, who will be able to recover information at any time it is necessary.

Information must be stored in a secure system with sufficient future storage space (e.g., for analyzer information backup). Time of document retention must be defined and documented by the laboratory in compliance with legal requirements. The procedure for document identification and disposal must also be established in accordance with the established retention time, while at the same time guaranteeing confidentiality. This procedure can be either performed by the laboratory or by an authorized supplier based upon a previous agreement.

Contingency result communication plan

Section 5.10.3 of the ISO 15189 standard on information system management establishes that the laboratory must design and document contingency plans to guarantee the provision of its services in case of technical fault or interruption. If there is a HIS or LIS failure, the ordering physician will activate the contingency plan and inform the heads of the involved hospital services.

The contingency plan must consider different scenarios and clearly define the actions to be taken and the professional responsible for each action.[18] Situations that may arise include a failure of the HIS and/or LIS, or the interruption of communication between the HIS and LIS. These situations may be solved by using paper test requests, manually entering data into the LIS, scheduling tests in the different analyzers, printing results from the different analyzers and their interpretative comments, and sending a copy of the test request with the results attached to the requesting service, or by remote printing of reports in printers for that intended use. Once the event has been solved, the results obtained from the different analyzers must be entered into the LIS and the laboratory must verify that all requests are complete.

Other potential scenarios include unauthorized access to the HIS or LIS (i.e., hackers); a failure of the hospital telephone line, which will involve the use of emergency phones in the laboratory and emergency care services connected to the power grid; or a failure in the pneumatic delivery tube, which will involve sending samples through porters.

Other situations in which laboratory services may be interrupted include the breakdown of an analyzer system, auxiliary equipment, refrigerator, or freezer; interruption of the electricity or water supply; or other exceptional situations (e.g., fire, earthquake, or other natural disaster). In these situations, the laboratory must guarantee the continuity of its services by adding annexes to the general plan or designing different contingency plans for some specific areas. These plans must clearly establish priorities and work coordination tasks, while also evaluating the human resources needed. These plans should also specify the procedure for manual sample entry, storage for later processing, testing in duplicate analyzers or systems, or shipping samples to other facilities under proper conditions, where applicable.

The characteristics of the contingency plan are detailed in Figure 4.


Fig4 Yeste AdvLabMed2021 2-3.jpg

Figure 4. Main laboratory information management requirements

Use of the ENAC label in result reports

Accreditation bodies like Spain's ENAC establish the conditions for accredited laboratories to give proof of their accreditation by the use of the their label. In the case of ENAC, reports of results obtained in an accredited activity can be marked with the ENAC label as proof of being an accredited activity. As described in CEA-ENAC-01 Requirements for the use of the ENAC label and reference of certification[5] document, the ENAC label is the combination of the ENAC trademark (or the accreditation reference), the accredited activity, and the accreditation number.

The label is always associated with the name or trademark of the accredited organization and should appear at least on the first page of the report. If accredited activities are performed in different facilities of the organization, the facility where the activity was performed should be specified.

When the result report includes an accredited activity, the ENAC label can be used or a statement can be included in the report such as “ENAC-accredited laboratory with reference number…,” as established in Section 11.2 of CEA-ENAC-01. The statement must be written with the same font size and style as the ones used in the body of the report and be readable.

To avoid confusion and make accredited results easily identifiable when not all activities are accredited, the labs should mark with a symbol (e.g., an asterisk or similar) the analytes that are not accredited and include a legend in a visible place near the label indicating that the marked analytes are not accredited. Alternatively, they could place a symbol or a legend next to the accredited analytes indicating their accreditation status. In case a symbol is used, a legend should be added to the report.

In some circumstances, a report may not bear the ENAC label although it contains results for accredited analytes. In this case, prior to the delivery of results, customers will be informed of such circumstance and its associated consequences and give consent. These cases are exceptional, as when there is prior explicit request and approval of the ordering physician (in this case, the accredited organization will inform the customer that a report not bearing the ENAC label is not considered accredited to all effects); when, for technical reasons, the accredited organization cannot temporarily comply with one or several accreditation requirements (in these cases, an explanatory note will be included in the report); or when placing the label in the result report is not possible (e.g., when the customer displays results on a web portal).

When an accredited laboratory reports results of activities performed in an external laboratory, these activities will be clearly identified and labeled as ENAC-accredited or non-accredited activities. (For further information about the use of the ENAC label, see the CEA-ENAC-01 document.[5])

Table 2 summarizes the main indications for the use of the label in result reports.

Table 2. Main indications for the use of the ENAC label in result reports
1. If the report includes an accredited activity, include the label or explanatory note detailing the accreditation number.
2. When only some of the analytes reported are accredited, identify either non-accredited analytes or accredited analytes. Include an explanatory note next to the analyte or on a footnote providing the accreditation number. Note that the label cannot be used if none of the reported activities are accredited.
3. Unlabeled reports may be issued on the customer's express request, when the laboratory is temporarily unable to comply with accreditation requirements (include an explanatory note in the report), or when use is not practically feasible (e.g., when displaying on a web portal).
4. If accredited activities are performed by an accredited external laboratory, clearly identify the activities performed by that external laboratory. If non-accredited activities are performed by an accredited external laboratory, an explanatory note may be included indicating the accreditation number of the external laboratory, but the label cannot be used.
5. The label has flexible scope of use: accredited tests can be shown in a list of accredited tests, classified by categories.

Acknowledgements

Author contributions

All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

Funding

None declared.

Conflict of interest

Authors state no conflict of interest.

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Notes

This presentation is faithful to the original, with only a few minor changes to presentation, spelling, and grammar. In some cases important information was missing from the references, and that information was added.