Category: Practice & Regulation | Estimated reading time: 10 minutes
From Concept to Practice
Understanding that QA prevents errors and QC detects them is the first step. The next step is more concrete: what are the components of QA, and how does each work in the context of day-to-day laboratory operations?
There are six components that need to be understood — four of which are relevant for all laboratories without exception, and the other two are formally required for accredited laboratories (though the concepts remain beneficial for those not yet accredited).
1. Living SOPs — Not SOPs That Just Sit in a Cupboard
Relevant for: all laboratories
Not SOPs that just sit in a cupboard. Living SOPs = followed, understood by all analysts, revised periodically, and supported by training evidence.
This is one of the most honest statements about the reality of laboratories in Indonesia — and perhaps in many other developing countries. SOPs exist. But whether SOPs are actually followed is a different story.
Dead SOPs are documents created during accreditation preparation, stored in a folder, and never opened again until the next audit. They may no longer reflect the actual procedures at the bench — because instruments have changed, reagents are different, but the SOPs have not been updated.
Living SOPs are documents that are actively used — not because someone is watching, but because the medical laboratory technicians (ATLM) understand that the SOPs are the result of collective experience on the best way to do things. The four elements are:
- Followed — no "shortcuts" that are considered acceptable because "we are used to it" or "the result is the same anyway." Every step has a reason, and that reason is understood, not just blindly obeyed.
- Understood by all ATLM — it is not just the supervisor who knows why a procedure is designed a certain way. Every ATLM must understand the principles behind every step, so that when a situation arises that is not covered in the SOP, they can make an appropriate decision based on those principles.
- Revised periodically — good SOPs continue to evolve. Every change in instrumentation, reagent, or method must be reflected in them. Every finding from QC reject investigations that successfully identifies a procedural issue must be integrated into the updated SOP.
- Evidence of training — documentation that every ATLM has read, understood, and been trained to execute the SOP. This is not just a signature on an attendance sheet, but verified evidence of competence.
A study on pre-analytical errors in the UK by Cornes and colleagues (2016) found that inconsistency in following SOPs is one of the primary causes of pre-analytical variation that is not detected by analytical QC systems — reinforcing the argument that living SOPs are a fundamental investment in quality.
2. Calibration & Maintenance — A Foundation That Must Not Be Ignored
Relevant for: all laboratories
Written calibration schedules that are strictly followed. Daily, weekly, and monthly maintenance documented. Instrument history logs maintained.
Calibration and maintenance are often treated as separate activities — when in fact, they are part of one integrated instrument management system.
Calibration is the process of verifying and adjusting the relationship between the instrument response and the true value. Without a scheduled and followed calibration, the instrument can experience gradual drift — small shifts that accumulate until they are large enough to affect patient results in a clinically meaningful way. Proper calibration includes: the use of valid calibrators (not expired, stored correctly, lot verified); documentation of calibration results — not just "calibration done"; verification of calibration with control materials after every session; and understanding when calibration is required more frequently — after major maintenance, after a reagent lot change, or when QC shows systematic trends.
Maintenance is a series of routine activities that ensure the instrument performs optimally, categorized into three levels:
- Daily — probe cleaning, fluid checks, verification of the instrument's physical condition. This is most often skipped because it feels "unimportant" when busy — yet inconsistency over many years is a major cause of premature, expensive instrument failure.
- Weekly — fluidic system cleaning, cleaning solution replacement, filter checks. Usually requires an extra 15–30 minutes.
- Monthly/periodic — according to manufacturer recommendations: replacement of components with a limited lifespan, internal component calibration, and comprehensive checks by a technician.
Instrument history — documentation of all calibration, maintenance, repair activities, and technical issues that have occurred, along with dates, details, and the personnel involved. This is invaluable during investigations, because the cause of today’s QC issue is often something that happened last week that was not documented.
3. ATLM Training & Competency — The Most Underrated Investment
Relevant for: all laboratories
Periodic competency testing, not just during onboarding. Including: pipetting technique, sample handling, and result interpretation.
Of all QA components, ATLM training and competency are the most minimally invested in — yet they have the biggest impact when invested in seriously.
Competency is not a static condition achieved once and maintained forever. It is dynamic — it can improve with experience and training, but it can also decline over time, especially for procedures that are rarely performed or that require fine motor skills. Even experienced ATLM can develop habits that slightly deviate from correct techniques without realizing it — without visible impact on individual measurements, but with a significant impact on the CV in the long run.
Periodic competency testing is not about "suspecting" the analyst — it is a mechanism to ensure standards are maintained and to identify additional training needs before they become quality issues. Three key competency areas:
- Pipetting technique — sounds too basic to mention, but variation in pipetting technique is one of the most significant sources of random error in manual laboratories. Pipette angle, aspiration speed, tip position in the sample, dead volume — all impact the accuracy and precision measured in the CV.
- Sample handling — how to receive, identify, store, and prepare samples prior to analysis. This is a pre-analytical domain completely outside the reach of analytical QC, and its impact on result quality is immense.
- Result interpretation — the ability to recognize results that are clinically implausible, correlate results with the patient's known condition, and make appropriate decisions regarding when confirmation or escalation is needed.
4. Reagent & Control Material Management — A Frequently Underestimated System
Relevant for: all laboratories
FIFO, monitored storage temperature, new lots verified before use, control materials not expired.
These four elements cover the entire lifecycle of reagent management from receipt to use.
FIFO (First In First Out) — reagents received first must be used first, not just those that are easiest to reach. A FIFO system that is not strictly enforced is the silent cause of many expired or degraded reagent issues that go undetected.
Monitored storage temperature — having a temperature-controlled refrigerator is not enough. The temperature must be actively monitored: there should be calibrated thermometers, daily temperature recording, and clear procedures for situations where the temperature deviates from the required range. Repeated temperature fluctuations — refrigerators opened and closed frequently, or compressors that are no longer efficient — are common causes of gradual reagent degradation that are very difficult to detect without a good monitoring system.
New lots verified before use — this means not just running a repeat of the preliminary control test, but also verifying that the new reagent lot produces results consistent with the previous lot, with parallel testing on a number of patient samples before the new lot is used fully.
Control materials not expired — it sounds very obvious, but audit findings in many laboratories show that the use of control materials that have passed their expiration date, or have been opened for too long, is a much more common problem than it should be.
5. Internal Audit — Not Just for Accreditation Preparation
Relevant for: accredited laboratories (formally); good practice for all
Periodic examination of all processes — not just during accreditation preparation. Audit findings = input for improvement.
The label "accredited lab" here needs to be read carefully — it does not mean that laboratories that are not yet accredited do not need internal audits. It means accredited laboratories are required to do so formally, but the concept — periodic examination of whether all procedures are being executed as intended — is a good practice relevant to all laboratories.
An effective internal audit is a systematic and scheduled process to examine: whether SOPs are followed correctly in actual practice; whether documentation is complete and accurate; whether equipment and storage conditions meet requirements; whether the QC system runs according to procedure; and whether ATLM training and competency are documented.
Audit findings = input for improvement — this is the point most often misunderstood. The goal of an audit is not to "find errors" or "punish," but to identify opportunities for improvement before problems grow larger. Laboratories that view audit findings as a threat will tend to hide problems. Laboratories that view them as valuable information will use them to build a better system.
6. CAPA — Corrective & Preventive Action
Relevant for: accredited laboratories (formally); good practice for all
Every QC problem must have a CAPA. Corrective = fix what has already happened. Preventive = prevent recurrence.
CAPA is the most "downstream" component of QA — it works after a problem has been detected, either by QC or internal audit. But it is the most decisive factor in whether the laboratory's quality system is truly evolving over time, or just spinning in place.
Corrective Action — a response to a problem that has already occurred: repeated QC rejects, significant audit findings, clinician complaints. Effective corrective actions do not just fix the manifestation of the problem (replace reagents, recalibrate), but identify and fix the root cause. Root Cause Analysis (RCA) methodology — by asking "why" repeatedly (5 Whys) — is a very useful tool here.
Conclusion
These six components — living SOPs, calibration and maintenance, training and competency, reagent management, internal audit, and CAPA — are not six separate activities. They are one mutually reinforcing system.
A good SOP is only effective if there is training that ensures ATLM follow it. Good training is only effective if there is an audit that verifies its consistency. An effective audit is only meaningful if there is a CAPA that follows up on its findings. And a good CAPA will result in updated SOPs — closing the cycle and bringing the system to a higher level.
This is what is meant by continuous improvement — not a slogan, but a real, recurring cycle that builds upon itself.