There are many threats to data integrity throughout the analytical process. One area that deserves special attention is instrument setup and data acquisition in a chromatography data system (CDS)—because these steps introduce new opportunities for human error and data manipulation. In this article, we offer advice on how to thwart these data integrity challenges. We start with the assumption that the CDS is properly configured for protecting electronic records, validated, and uses electronic signatures.
Be wary of automated transfers of additional values.
Chromatography assays often require the input of additional data values to generate results for comparison against specifications. These additional values directly impact the accuracy of the calculated result; therefore, they must be right. Some laboratories have developed automated tools to transfer these values from an electronic laboratory notebook (ELN) or laboratory execution system (LES) to a CDS. However, automated transfer can pose data integrity risks:
- Data values manually entered into an ELN or LES, then electronically transferred into a chromatography method, have the same human error risks as data values entered directly into the chromatography system.
- When interface files are placed in a target directory to be later collected and processed into the chromatography system, the target directory provides a convenient place for someone to insert an altered data value into the chromatography calculations.
To avoid these data integrity issues, make sure the ELN or LES performs validity checks or other risk-reduction actions at the time of data entry. And make sure there is an easily reviewable, robust audit trail for actions in the target directory, particularly around calculation and factor changes.
Fight obfuscation with clear audit trails.
One technique for data manipulation is obfuscation—piling on layers of data to make it difficult for reviewers to sort fact from fiction. A tangled mess of an audit trail, with multiple changes and timestamps, makes it tempting for reviewers to simply accept the value and move on. So make sure your CDS has clear audit trails, formatted for easy review, to streamline reviews and make it more difficult to use obfuscation. And during the quality review, look for test patterns where numerous changes are made, and dig into the data to verify the validity of changes.
Look carefully at the system suitability process.
Chromatographic methods have some series of injections that verify the suitability of the instrument before reference standard and sample injections are made. Failure of the suitability test is justification for invalidation of all subsequent standard and sample injections in the test run. Therefore, data reviewers must look carefully at the suitability process, especially when the test run is to be declared invalid along with test results—such as a situation where the system suitability sample, standard, and samples were placed in an autosampler and assayed overnight without human intervention.
When test results have been generated, look at the potential data values for potential failures as part of the system suitability review. Your chromatography procedure should answer the following questions:
- When are extra (unplanned) injections acceptable?
- If they fail to meet expectations, will they result in repeats or investigations?
- How many repeats are acceptable? When do they stop?
- How will the unplanned injections be reviewed to determine scientific validity?
Manage aborted runs as unplanned events.
While collecting data, it may be necessary to abort a run because of any number of issues that impact the test run. But there can be a dark side: aborted runs can be used as a means of stopping the chromatography system from generating out-of-specification (OOS) test results.
For this reason, it is important to manage aborted runs as unplanned events and review the system for the number of aborted runs, along with the group, person, method, instrument, and abort reason comment associated with the aborted run. Also, look for trends in aborted runs, and include aborted runs with the subsequent test record.
Be suspicious of “alternate” directories.
One issue that has found its way into some laboratories is diversion of test data into alternate directories. For example, test runs with failing injections are placed into a folder named “Test” to make them appear as non-production test results.
You can detect this type of ruse by creating a report to inventory test runs referenced in reported test results, looking for missing runs in the sequence (each run is given a unique identification by the system). A second detection report can look for the presence of folders or injections with suspicious names like “Test,” “Practice,” or other terms that merit review. To ensure data integrity, lab staff must be trained to submit every injection for data review. When data are rejected for use, a reason for that rejection must be documented to defend the data exclusion from the reported values.
Make sure management is on board.
Ultimately, data integrity depends on management support. Throughout the process of instrument setup and data collection, management must set the expectation to follow the chromatography procedure and fully report all values generated—whether used for calculations or not. Management is also responsible for ensuring that the system is capable of securing data during the testing process and is configured to capture actions in audit trails that assist the data reviewer. It is especially important for management to expect unplanned injections to be minimized and not used as a substitute for investigating a substandard instrument or method to understand failures and prevent their recurrence.
Close down data manipulation with OpenLab CDS.
Correct, complete, and accurate data acquisition is a key component of data integrity. OpenLab CDS software helps you strengthen data integrity by helping you identify errors and thwart attempts at data manipulation. Here are just a few key features and capabilities relevant to instrument setup and CDS data acquisition:
- Configurable user roles or types to avoid conflicts of interest—for example, no user should have administration privileges. Roles are used to assign privileges to a user or a user group globally or for a specific instrument, project, project group or location.
- Mandatory login for accessing instruments. Instruments are restricted to users with proper authorizations.
- Audit trail functionality covering the whole system, along with audit trails to highlight changes to and deletions of different data types: sequence, method, injection, and result sets. The audit trail captures the user ID, date and time of the change, and before and after values with a reason why the change was made. This capability enables you to rapidly trace and review all sample related data—method version, instrument, raw data location, acquisition computer, etc.
For more detailed tips and advice about preserving data integrity, check out the related content below.