LabQMHub Editorial Team · ISO 15189:2022 Quality Management Series
No laboratory operates in complete isolation. Referral laboratories perform specialized testing beyond a facility’s own scope, equipment service engineers maintain critical instruments, and courier services transport specimens between sites — every one of these external relationships can affect the quality of a laboratory’s ultimate results, even though the laboratory itself never directly controls the external party’s internal processes.
ISO 15189:2022’s requirements for service agreements and external providers, under Clause 6.6, address how a laboratory extends its own quality expectations outward to the partners it depends on, without pretending it can control what it cannot directly oversee.
Why External Provider Quality Is the Laboratory’s Responsibility
When a laboratory refers a specimen to another facility for specialized testing, the referring laboratory does not transfer away its responsibility to the patient — the result still returns under the referring laboratory’s clinical relationship, and any error in the referral chain still affects that patient’s care. This is why ISO 15189:2022 requires laboratories to actively select, evaluate, and monitor external providers, rather than treating referral or outsourcing arrangements as someone else’s quality problem.
The same logic applies to equipment service providers, whose maintenance and repair work directly affects the accuracy of instruments covered in this program’s earlier equipment course, and to any other externally provided product or service that touches the laboratory’s ability to produce accurate, timely results.
Formal Service Agreements: Defining Expectations in Writing
A documented service agreement should specify the scope of services provided, expected turnaround times, quality and performance standards, communication protocols for problems or delays, and each party’s specific responsibilities — leaving as little as possible to informal understanding or assumption, which tends to break down precisely when something goes wrong and clarity matters most.
Service agreements should be reviewed periodically, not signed once and filed away indefinitely, since a provider’s performance, ownership, or capabilities can change substantially over the life of a laboratory’s relationship with them, and an outdated agreement provides false assurance rather than genuine protection.
Selecting and Evaluating Referral Laboratories
Referral laboratories should themselves hold appropriate accreditation or demonstrate equivalent quality assurance, and a laboratory sending specimens externally should verify this status rather than simply accepting a referral partner’s own assurances at face value. Ongoing performance monitoring — turnaround time tracking, result quality feedback, and complaint patterns related to referred testing — should feed into periodic supplier review.
This evaluation and monitoring connects directly to the quality indicator monitoring covered later in this program: referral laboratory performance is itself an appropriate category of indicator to track, since problems in outsourced testing are otherwise easy for the referring laboratory to lose visibility into.
When External Provider Performance Falls Short
A laboratory needs a clear process for what happens when an external provider’s performance falls below agreed standards — repeated late turnaround times, quality concerns, or communication failures should trigger a formal review with the provider, not simply quiet, ongoing tolerance because switching providers feels administratively burdensome.
In serious or repeated cases, this review process should include a defined escalation path, potentially culminating in a decision to change providers — a decision that should never be delayed so long that patient care is meaningfully compromised by a relationship the laboratory has already identified as underperforming.
Frequently Asked Questions
Does a laboratory remain responsible for results from a referral laboratory?
Yes — the referring laboratory retains responsibility to the patient and clinician, which is why ISO 15189:2022 requires active selection, verification, and ongoing monitoring of referral partners.
What should a laboratory service agreement include?
Scope of services, expected turnaround times, quality and performance standards, communication protocols for problems, and clearly defined responsibilities for each party.
How should a laboratory respond to a consistently underperforming external provider?
Through a formal review process with defined escalation, potentially including a documented decision to change providers if performance does not improve within a reasonable timeframe.
Key Takeaways
- A laboratory retains responsibility to the patient even when testing or services are performed by an external provider.
- Formal, documented service agreements should specify scope, turnaround expectations, quality standards, and communication protocols.
- Service agreements need periodic review, since provider capabilities and performance can change substantially over time.
- Referral laboratories should be verified for appropriate accreditation, not accepted on the basis of self-reported assurances alone.
- Referral and external provider performance should be monitored as an ongoing quality indicator, not assessed only at initial selection.
- A clear escalation process should exist for underperforming providers, up to and including a documented decision to change providers.
Conclusion
External providers extend a laboratory’s capabilities, but they also extend its risk exposure — and ISO 15189:2022 recognizes that a laboratory cannot outsource its accountability for patient outcomes along with the testing itself. Formal agreements and ongoing monitoring are what keep external relationships from becoming an unmanaged blind spot in an otherwise well-controlled quality system.
Treating external providers with the same quality rigor applied to internal processes closes a gap that, left unmanaged, can quietly undermine an otherwise excellent laboratory’s reputation and patient outcomes.
Explore how pre-examination processes begin the total testing process in the next course of this ISO 15189:2022 training series, opening Track 4.
Source note: this article draws on “Quality Management in Clinical Laboratory Demystified” by Dr. Taleb Chalab Cham, ISO 15189:2022, and widely recognized clinical laboratory quality references including CLSI guidelines, CAP accreditation checklists, and WHO laboratory quality guidance.
