An auditor asks for the history of a sample.
Can your lab show where it came from, who handled it, where it was stored, what happened to it, and when each step occurred?
If answering that question means searching through spreadsheets, paper logs, emails, and separate systems, the problem is bigger than the audit. The lab may have the records, but not a reliable way to connect them.
That is where sample traceability becomes critical.
A traceable sample record allows a lab to reconstruct a sample’s journey from receipt through processing, storage, testing, transfer, and final disposition. When that history is consistently captured and easy to retrieve, audit preparation becomes less about scrambling for evidence and more about demonstrating a process that is already under control.
What Does Sample Traceability Mean in a Laboratory?
Sample traceability is the ability to follow a sample through its lifecycle and establish what happened to it at each important stage.
Depending on the laboratory and type of work, this can include:
- When and where the sample was received
- Its unique identification
- Who handled or processed it
- Where it was stored
- When it was moved or transferred
- What testing or processing was performed
- Related results and records
- Changes made to its information
- Its current status or final disposition
This is closely related to chain of custody and audit trails, but the terms are not interchangeable.
Chain of custody focuses on the documented control and transfer of a sample between people or locations. An audit trail records the history of actions or changes made to electronic records. Sample traceability brings the broader lifecycle together so that the history of the sample can be reconstructed.
The goal is simple: if someone asks about a sample, the lab should be able to tell its story from its records.
Why Traceable Sample Tracking Matters During a Lab Audit
Audits often come down to evidence.
Policies and procedures explain what a laboratory is supposed to do. Records demonstrate what actually happened.
For sample management, an auditor may move beyond the procedure and examine an individual sample record. They may want to establish when it arrived, who handled it, where it was stored, and what happened afterward.
A consistent sample tracking process makes that evidence easier to demonstrate. It also reduces reliance on memory and manual reconstruction when information is spread across different sources.
For electronic records, changes should also remain transparent rather than obscuring the information that was originally recorded. FDA guidance on electronic systems, records, and audit trails describes audit trails as a way to reconstruct the history of electronic records, including relevant information about who made changes and when.
What Auditors Need to Trace Through a Sample’s Lifecycle
A useful way to assess audit readiness is to start with the sample itself.
Starting with a sample ID, could someone reconstruct its history without searching through several disconnected records?
The evidence should cover the important points in the sample’s lifecycle.
Sample Identification and Receipt
The record should establish what the sample is, where it came from, when it was received, and how it was uniquely identified.
Handling and Processing
Relevant preparation, processing, or handling activities should be associated with the sample and the person responsible.
Storage and Movement
The record should provide visibility into where the sample has been stored and, where relevant, when it moved between storage, processing, testing, or other locations.
Testing and Related Records
Testing, processing, and results should remain connected to the sample so that the information can be reviewed as part of the same history.
Changes to Records
Important changes to sample information should remain traceable rather than simply replacing the previous information.
Final Disposition
The record should show what ultimately happened to the sample, whether it was retained, transferred, released, or disposed of according to the laboratory’s procedures.
The exact information required will vary by laboratory, sample type, workflow, and applicable requirements. The principle remains the same: the sample record should tell a coherent story from beginning to end.
6 Sample Tracking Practices That Improve Audit Readiness
Once the required evidence is clear, the next step is making sure the tracking process captures it consistently.
1. Standardize Sample Identification
Use a consistent unique identifier for every sample and the records associated with it.
This gives staff a reliable starting point for finding information and reduces the risk of duplicate or ambiguous records.
2. Capture Movements at the Time They Occur
Record important sample movements as part of the workflow rather than reconstructing them later.
A history such as:
Storage → Processing → Testing → Storage
provides much more context than a record showing only the current location.
3. Attribute Important Activities
Where relevant, record who performed an activity and when it occurred.
This creates accountability and gives the laboratory a stronger record of how the sample was handled.
4. Keep Corrections Traceable
Sample information may need to be corrected or updated. Those changes should not make the previous history impossible to understand.
Maintaining relevant change history helps preserve the integrity of the record over time.
5. Link Related Laboratory Information
Keep sample records connected with the testing, processing, inventory, and result information that belongs to them.
This reduces the amount of manual searching required when someone needs to investigate a sample.
6. Make the History Easy to Retrieve
Traceability loses much of its value if staff cannot find the information when they need it.
A useful process should allow the team to start with a sample ID and quickly locate the relevant history.
Common Sample Tracking Gaps That Create Audit Problems
The easiest way to spot a traceability problem is to look at where the sample record breaks down.
Common warning signs include:
- Sample information spread across spreadsheets and paper logs
- Current locations recorded without a reliable movement history
- Transfers documented inconsistently
- Conflicting information across different systems
- Shared accounts that make user attribution difficult
- Corrections that overwrite previous information
- Sample records disconnected from testing or processing data
- Records that technically exist but take too long to retrieve
These gaps can be easy to overlook during routine work because staff may already know where information is stored or remember what happened to a particular sample.
That changes when an auditor asks for a sample the team did not expect.
For audit readiness, the objective is not simply to keep records. It is to keep records that can be connected, traced, and retrieved.
How to Test Whether Your Lab’s Sample Tracking Is Audit-Ready
You do not have to wait for an audit to find out whether your tracking process works.
Pick a sample at random and ask someone to reconstruct its history without relying on the person who originally handled it.
Ask:
- What is the sample and where did it come from?
- When was it received?
- Who handled it?
- Where has it been stored?
- Has it been transferred or moved?
- What processing or testing has been performed?
- Are related results and records available?
- Have important changes been made to its record?
- Where is it now?
- Can the complete history be retrieved without searching through multiple disconnected sources?
Pay attention not only to whether the answers exist, but to how quickly they can be found.
If your team can answer the questions using connected records, that is a strong foundation for audit readiness.
If the exercise requires multiple files, several employees, or manual reconstruction, you have identified a process weakness before an actual audit does.
Running this test periodically can also help identify problems as workflows change or sample volumes increase.
Choosing a Sample Tracking System for Better Traceability
For laboratories managing large numbers of samples or complex workflows, maintaining connected records manually can become difficult.
This is where LIMS sample tracking can provide a more structured approach by bringing sample information, movements, activities, and related laboratory data into a connected workflow.
A LIMS can help centralize sample information and make key parts of the sample lifecycle easier to manage. A system such as QISS LAB combines sample management with other laboratory data and workflows.
When evaluating sample management software, look beyond whether it can simply store sample information. Consider whether it supports the way your laboratory actually tracks samples.
Useful capabilities to evaluate include:
- Unique sample identification
- Sample lifecycle tracking
- Storage and location management
- Sample movement and transfer history
- User-level activity records
- Audit trails for relevant changes
- Connections between samples and related laboratory data
- Searchable records and reporting
The objective is not simply to replace a spreadsheet with another database.
It is to create a reliable, accessible history of what happened to each sample. When sample information and related activities can be connected in one system, the laboratory spends less time reconstructing records and more time using them.
Sample Tracking Audit-Readiness Checklist
Use this checklist to quickly assess your laboratory’s current sample tracking process:
☐ Every sample has a unique identifier.
☐ Sample origin and receipt information are recorded.
☐ Sample handling activities are traceable.
☐ Storage locations and movements are documented.
☐ Transfers are recorded.
☐ Relevant activities can be attributed to users.
☐ Important record changes can be traced.
☐ Related sample data and results are accessible.
☐ Sample histories can be retrieved quickly.
☐ Staff are following the documented tracking process.
Audit readiness should not begin when an auditor arrives.
When sample tracking is built into everyday laboratory workflows, the evidence needed for an audit is created as the work happens. Instead of spending hours reconstructing a sample’s history, your team can retrieve the relevant records and show what happened, when it happened, and who was involved.
The result is not just a smoother audit. It is a more organized, accountable, and reliable approach to managing samples every day.
Ready to make sample management easier to track and audit? Request a free QISS LAB demo
