Preparing for ISO 15189:2022 Accreditation

ISO 15189 is the internationally recognised standard for medical laboratory quality and competence. The 2022 revision, published in December 2022, represents the most significant update to the standard in a decade. For laboratories in the United Kingdom, UKAS (the United Kingdom Accreditation Service) has set a transition deadline of December 2025, by which all accredited laboratories must demonstrate conformity with the new edition. Whether your laboratory is already accredited to ISO 15189:2012 or pursuing accreditation for the first time, understanding the changes and their implications for your LIMS and wider quality management system is essential.

This article provides a practical overview of the key changes introduced in ISO 15189:2022 and what they mean for laboratory managers and quality leads in UK pathology laboratories.

What Has Changed in the 2022 Revision?

The previous edition of ISO 15189, published in 2012, served UK laboratories well for over a decade. However, laboratory practice has evolved considerably during that time, with increasing digitalisation, growing emphasis on risk management, and changes in the broader regulatory landscape. The 2022 revision addresses these developments whilst bringing the standard into structural alignment with other accreditation frameworks.

Structural Alignment with ISO/IEC 17025

One of the most immediately noticeable changes is the restructured clause numbering. ISO 15189:2022 now follows the same high-level clause structure used by ISO/IEC 17025 (the standard for testing and calibration laboratories) and other conformity assessment standards. The familiar Clause 4 (Management Requirements) and Clause 5 (Technical Requirements) from the 2012 edition have been reorganised into a series of clauses covering:

• Clause 4: General requirements (impartiality and confidentiality)
• Clause 5: Structural requirements
• Clause 6: Resource requirements (personnel, facilities, equipment)
• Clause 7: Process requirements (pre-examination, examination, post-examination, and reporting)
• Clause 8: Management system requirements

This restructuring does not fundamentally change what laboratories must do, but it does change where you will find specific requirements in the standard. Laboratories transitioning from ISO 15189:2012 will need to update their quality management system documentation to reflect the new clause references. Cross-referencing tables mapping old clauses to new ones are widely available and are a useful starting point for this exercise.

The Transition Timeline

The International Accreditation Forum (IAF) allowed a three-year transition period from the date of publication, giving accredited laboratories until December 2025 to complete the transition. UKAS has followed this timeline and has been assessing laboratories against the 2022 edition during routine surveillance and reassessment visits. If your laboratory has not yet transitioned, urgent action is required.

Risk-Based Thinking

Perhaps the most significant conceptual change in ISO 15189:2022 is the explicit introduction of risk-based thinking throughout the standard. Whilst the 2012 edition touched upon risk in certain areas, the 2022 revision makes it a foundational principle that permeates every aspect of laboratory operations.

What Risk-Based Thinking Means in Practice

Risk-based thinking does not necessarily require a formal risk management framework (though many laboratories will find one helpful). It means that when designing processes, making decisions, and implementing controls, laboratories should systematically consider what could go wrong, how likely it is, and what the consequences would be. This should inform the level of control applied to each process.

The standard expects laboratories to identify risks and opportunities across the entire examination process, from the moment a test is requested to the point at which results are communicated to the requesting clinician. This encompasses the pre-examination, examination, and post-examination phases.

Pre-Examination Risks in Histopathology

For histopathology laboratories, pre-examination risks are particularly significant and include:

• Specimen labelling errors: Mislabelled or unlabelled specimens arriving from theatres or clinics represent one of the most serious risks in pathology. Laboratories should have documented procedures for handling discrepancies and a risk-assessed approach to specimen acceptance criteria.
• Fixation failures: Inadequate fixation, incorrect fixative type, or prolonged ischaemia time can compromise tissue quality and downstream testing (for example, immunohistochemistry or molecular analysis). Risk assessment should consider the impact of fixation variables on diagnostic reliability.
• Specimen mix-up: The risk of transposing specimens between patients during accessioning, grossing, or embedding is a well-recognised hazard. Controls such as single-specimen processing, barcode verification, and two-person checks should be proportionate to the assessed risk.
• Request form deficiencies: Incomplete clinical information on request forms can affect the quality of pathological interpretation. Laboratories should assess the risk associated with missing data and have procedures for seeking additional information when it is clinically necessary.

Documenting Your Risk Approach

UKAS expects to see evidence that risk-based thinking is embedded in laboratory processes rather than treated as a standalone activity. This means risk considerations should be documented within standard operating procedures (SOPs), reflected in process design, and reviewed as part of the management review process. A risk register is a useful tool but is not sufficient on its own; assessors will look for evidence that identified risks have led to tangible actions and controls.

Impartiality and Confidentiality

ISO 15189:2022 strengthens the requirements around impartiality and confidentiality, elevating them to standalone clauses (Clause 4.1 and 4.2) rather than embedding them within broader management requirements as in the 2012 edition.

Demonstrating Impartiality

Laboratories must now identify risks to impartiality on an ongoing basis and demonstrate that they have mechanisms in place to mitigate them. In practice, this means documenting potential conflicts of interest that could influence laboratory activities or results. Examples include commercial pressures to reduce turnaround times at the expense of quality, relationships with suppliers that could bias equipment or reagent selection, and financial incentives linked to test volumes.

For NHS pathology laboratories, impartiality considerations might also include the influence of commissioning arrangements or network partnerships on service delivery. The standard requires that laboratory personnel are free from undue internal and external pressures that could affect their work.

Confidentiality and Data Protection

The confidentiality requirements in the 2022 edition are more explicit and align well with the UK General Data Protection Regulation (UK GDPR) and the Data Protection Act 2018. Laboratories must ensure that patient information is protected throughout the examination process, including during electronic transmission and storage.

Your LIMS plays a central role here. Access controls, role-based permissions, encryption of data in transit and at rest, and secure audit trails all contribute to meeting both ISO 15189:2022 confidentiality requirements and data protection legislation. Laboratories should review their LIMS access policies to ensure that the principle of least privilege is applied and that access reviews are conducted regularly.

Process Validation and Verification

The 2022 revision provides greater clarity on the distinction between validation and verification of examination procedures, and UKAS has published supplementary guidance (notably LAB 30) to support laboratories in meeting these requirements.

Validation of New Methods

When a laboratory introduces a new examination procedure that has not been previously validated for the intended use, full validation is required. This involves systematically confirming that the method is fit for its intended purpose by evaluating performance characteristics such as accuracy, precision, analytical sensitivity, analytical specificity, measuring range, and measurement uncertainty (where applicable).

For histopathology, validation considerations extend to immunohistochemistry protocols, molecular pathology assays, and any novel staining techniques. The validation documentation should be sufficiently detailed to allow a competent person to understand what was done, what results were obtained, and why the method was deemed acceptable.

Verification of Established Methods

When a laboratory adopts a previously validated method (for example, one published in a recognised textbook or provided by a manufacturer with CE-marked reagents), verification rather than full validation may be appropriate. Verification confirms that the laboratory can achieve the performance characteristics specified by the method developer within its own environment, using its own equipment and personnel.

UKAS expects verification records to include evidence that the laboratory has objectively confirmed the method performs as expected. Simply adopting a method without any local verification is not acceptable, even if it is widely used elsewhere.

Measurement Uncertainty

ISO 15189:2022 maintains the requirement to evaluate measurement uncertainty for quantitative examination procedures. Whilst this is more straightforward for clinical chemistry and haematology, histopathology laboratories should consider where quantitative elements exist in their work (for example, tumour percentage scoring, mitotic counts, or measurement of invasion depth) and whether uncertainty estimation is practicable and clinically meaningful.

Document Control and Information Management

Effective document control has always been a cornerstone of laboratory quality management, but ISO 15189:2022 places greater emphasis on information management systems and the governance of electronic records.

Electronic Document Management

Laboratories are expected to have robust systems for controlling documents, including SOPs, policies, forms, and work instructions. The standard requires that documents are reviewed at defined intervals, that obsolete versions are removed from points of use, and that changes are tracked with clear version control.

Many laboratories have moved to electronic document management systems (EDMS), which can support compliance by automating review reminders, maintaining version histories, and controlling access to current documents. Whether your document control system is paper-based or electronic, the fundamental requirements remain the same: documents must be approved before issue, accessible to those who need them, and protected against unauthorised changes.

LIMS as Part of the Document Control Framework

Your LIMS is itself a controlled system that generates records and documents. Configuration changes to LIMS workflows, report templates, coding structures, and user permissions should all be subject to change control. Laboratories should maintain records of LIMS configuration changes, including who authorised the change, when it was implemented, and what testing was performed to confirm the change was effective.

UKAS assessors frequently examine how laboratories manage LIMS changes and may ask to see evidence of change control procedures for recent system modifications. A well-maintained change log, linked to your broader document control system, is essential.

Audit Trails and Traceability

Traceability is a fundamental requirement of ISO 15189, and the 2022 edition reinforces the expectation that laboratories can demonstrate a complete chain of custody and data integrity from specimen receipt to final report.

The Role of LIMS Audit Trails

A LIMS audit trail provides an immutable record of every significant action taken within the system. This includes specimen registration, workflow step completion, result entry, report authorisation, and any amendments made after initial authorisation. For UKAS accreditation, the audit trail must be sufficiently detailed to reconstruct the history of any specimen or result if questions arise.

Key attributes of an effective audit trail include:

• User identification: Every action must be attributable to a specific, authenticated user. Shared login credentials undermine the integrity of the audit trail and are a common finding during UKAS assessments.
• Timestamps: All entries should be automatically timestamped by the system, with time synchronisation across networked devices.
• Immutability: Audit trail records should not be editable or deletable by standard users. Any system that allows modification of historical records without preserving the original entry and the reason for change is unlikely to satisfy UKAS requirements.
• Accessibility: Audit trail data should be readily retrievable for review during internal audits, incident investigations, and UKAS assessment visits.

Amendment Tracking and Authorisation

The standard requires that amendments to reported results are clearly documented, including the original result, the amended result, the reason for the amendment, and the identity of the person authorising the change. Amended reports must be clearly identifiable as such, and the original report must remain accessible.

Laboratories should review their LIMS amendment workflows to ensure they capture all required information and that amended reports are issued in a way that clearly communicates the change to the requesting clinician. UKAS will examine amendment records during assessment and expects to see a robust, auditable process.

Personnel Competence

ISO 15189:2022 expands the requirements for personnel competence, moving beyond initial training records to encompass ongoing competence monitoring and a more systematic approach to competence management.

Competence Assessment Framework

The standard requires laboratories to define competence requirements for each role, assess competence at defined intervals, and take action when competence gaps are identified. This applies to all personnel whose activities affect laboratory results, including biomedical scientists, pathologists, support staff, and anyone involved in pre-examination or post-examination processes.

A competence assessment framework should include:

• Initial competence assessment: Confirming that new staff or staff undertaking new roles can perform their duties to the required standard before working independently.
• Ongoing competence monitoring: Regular reassessment at defined intervals, typically annually, using methods such as direct observation, review of work output, participation in external quality assessment (EQA) schemes, and knowledge assessments.
• Training records: Comprehensive documentation of all training activities, including the date, content, trainer, and outcome. Records should demonstrate a clear link between identified training needs and completed training.
• Competence reviews: Periodic review of the competence assessment programme itself to ensure it remains effective and proportionate.

How LIMS Supports Competence Documentation

A well-configured LIMS can support competence management by restricting access to specific functions based on user role and training status. For example, only authorised pathologists should be able to release diagnostic reports, and only trained staff should be able to perform certain processing steps. These system-level controls provide an additional layer of assurance that work is performed by competent personnel.

Some laboratories also use their LIMS to track competence-related metrics, such as turnaround times by individual, error rates, and participation in quality assurance activities. Whilst the LIMS is not typically the primary repository for training records, it can provide valuable objective data to support competence assessments.

Preparing for UKAS Assessment

Transitioning to ISO 15189:2022 is a substantial undertaking, but a structured approach can make the process manageable. The following steps provide a practical roadmap for laboratories preparing for assessment against the new edition.

Conduct a Thorough Gap Analysis

Begin by obtaining a copy of ISO 15189:2022 and conducting a detailed gap analysis against your current quality management system. Compare each clause of the new standard with your existing documentation, processes, and practices. Identify areas where your current arrangements already satisfy the new requirements, areas where modifications are needed, and areas where entirely new processes or documentation must be developed.

Pay particular attention to the areas where the 2022 edition introduces genuinely new requirements, such as formalised risk-based thinking, strengthened impartiality provisions, and enhanced information management expectations. These are the areas most likely to require significant work.

Engage Your Team Early

Accreditation is not solely a quality department responsibility. Engage laboratory managers, section leads, biomedical scientists, and pathologists in the transition process from the outset. Staff who understand the reasons for the changes and their role in meeting the new requirements are far more likely to embed them effectively in their daily practice.

Consider running awareness sessions or workshops to introduce the key changes and gather feedback on how best to implement them within your laboratory's specific context. The people doing the work are often best placed to identify practical approaches to meeting new requirements.

Common Non-Conformities to Avoid

UKAS assessors have identified several recurring themes in non-conformities raised during transition assessments. Being aware of these common findings can help your laboratory avoid them:

• Superficial risk assessment: Risk registers that exist in name only, with no evidence that identified risks have been acted upon or reviewed. Assessors expect to see risk-based thinking embedded in processes, not confined to a standalone document.
• Incomplete method verification: Adopting methods without adequate local verification, or maintaining verification records that lack objective evidence of acceptable performance.
• Inadequate change control for LIMS: Making changes to LIMS configuration, workflows, or report templates without following a documented change control procedure.
• Shared user accounts: Multiple staff members sharing a single LIMS login, undermining the integrity of audit trails and user attribution.
• Overdue document reviews: Quality management system documents that have passed their scheduled review date without being reviewed and re-approved.
• Competence assessment gaps: Missing or incomplete competence records for specific staff members, or competence assessments that do not cover all relevant aspects of the role.
• Poorly documented impartiality considerations: Failure to identify and document risks to impartiality, particularly in laboratories that also provide consultancy or referral services.

Plan for Continuous Improvement

ISO 15189:2022, like its predecessor, is built on the principle of continuous improvement. Achieving accreditation is not the end point; maintaining and improving your quality management system is an ongoing responsibility. Use internal audits, management reviews, incident reports, and feedback from UKAS assessments to identify opportunities for improvement and ensure that your quality management system evolves alongside your laboratory's activities.

The transition to ISO 15189:2022 is an opportunity to strengthen your laboratory's quality management system, not merely a compliance exercise. Laboratories that approach the transition with this mindset will derive the greatest benefit from the process.

The key to a successful transition lies in starting early, engaging your entire team, and taking a systematic approach to identifying and addressing gaps. With the December 2025 deadline upon us, now is the time to ensure your laboratory is fully prepared.