How to qualify an outsourced microbiology laboratory

Qualifying an external laboratory means demonstrating that it can perform the required service and keep it under control. A certificate, price or previous satisfactory test report contributes to the assessment; it is not the whole decision.

1. Define the service before selecting a supplier

Describe tests, matrices, methods, sites, volumes, workload variation and supported decisions: release, stability, monitoring or investigation. Specify who samples, accompanying information, required turnaround and urgent-result handling. Distinguish technical test duration from total time to reviewed data.

Identify applicable markets and obligations. EU GMP Chapter 7, operative since 31 January 2013 assigns control of outsourced activities and assessment of the acceptor’s legality, suitability and competence to the contract giver. Outsourcing does not automatically transfer responsibility for the product decision.

2. Verify competence and actual scope

Examine relevant matrix experience, authorised personnel, equipment, facilities, methods, controls and available capacity. WHO good practices for pharmaceutical microbiology laboratories, 2011 help structure this technical assessment. Request evidence for the site that will actually perform the work.

The official ISO/IEC 17025:2017 description, confirmed in 2023 concerns laboratory competence, impartiality and consistent operation. The public scope was consulted, not the full standard. Verify accreditation status and scope relevant to method, matrix and site. Management-system certification, test accreditation and a GMP authorisation or certificate have different purposes and scopes; none automatically replaces the others.

3. Design an audit that supports the decision

Set audit depth, format and expertise according to service criticality, history, changes and information reliability. Connect documents to observable practice: trace a sample through to its report and reconstruct a closed anomaly. Record evidence, gap, risk, required action and closure criterion.

Original audit checklist:

• Does the site meet applicable authorisation requirements and have the required competence?
• Is the method suitable for the matrix, with documented controls?
• Are samples, media, incubation and readings traceable?
• Are OOS, changes and original data accessible and controlled?
• Have workload, absences, failures and service continuity been assessed?

Separate essential requirements from weighted preferences. A regulatory prohibition, unsuitable method or lack of necessary evidence access cannot be offset by high scores for price and speed. Document approval, restrictions or non-approval and decision ownership.

4. Control the method and sample journey

EU GMP Chapter 6, 2014, §§6.15 and 6.37–6.40 addresses method appropriateness and technical transfer. Assess transfer, necessary verification or validation, and suitability for the actual matrix separately. Receiving a procedure does not demonstrate the ability to execute it.

Agree sampling, container, identification, transport and storage conditions and times, receipt criteria, delays and nonconformities. Justify limits using relevant data rather than a single maximum holding time for every sample. Maintain chain of custody and identify who authorises testing, rejection or assessment of a nonconforming sample. See the workflow for environmental sample receipt and reading.

5. Turn the quality agreement into operating responsibilities

The agreement must fit the service, applicable requirements and contract, and be reviewed by competent functions. Chapter 7, §§7.11 and 7.14–7.17, addresses subcontracting, responsibilities, records and audit rights. The following original matrix is a proposal to adapt, not an approved contract.

6. Verify the data and report, not just the result

Define report content, units, method, deviations, result status and authorised reviewers. Agree access to original data, metadata, calculations and audit trails relevant to the risk and system. A summary PDF may not be enough to reconstruct a test or investigation.

Simulated case. A laboratory presents valid accreditation, but its test listing does not clearly cover the requested matrix. The giver checks scope, any flexibility, suitability evidence and applicable GMP requirements. It neither approves by logo alone nor rejects without clarifying scope. Work starts only after a documented decision on essential requirements and gaps.

7. Maintain qualification over time

Review changes in site, methods, key personnel, capacity and relevant authorisation or accreditation status. Monitor agreed turnaround, nonconforming samples, data completeness, recurring anomalies and effective CAPA closure. Define denominators and context: a low OOS rate alone does not prove better service.

Establish who assesses signals, when to intensify oversight and what conditions restrict or suspend the assignment. Chapter 7, §7.7, provides for performance monitoring and review. Maintain a shared, verifiable procedure for responsibilities during microbiological OOS investigations. Qualification covers the approved service; it is not permanent approval of every supplier activity.