RCL Batch Screen Audit

Audit completeness, controls, and negative results for caller-defined replication-competent lentivirus screens; not regulatory lot release.

Description

Audit required replication-competence screens against performed tests, negative-result flags, and valid-control flags.

Replication-competent lentivirus, abbreviated RCL, is a concern distinct from the intended function of a lentiviral vector. Testing records need to distinguish a negative result from a result whose controls are invalid. A complete audit also asks whether every test named in the applicable screening plan was performed.^[1]

This tool represents a screening plan as required test names and an aligned list of performed test names, negative-result flags, and control-validity flags. Those names and flags are supplied records, not assay interpretation inferred by the calculator.

RCL Batch Screen Audit lists missing tests, invalid-control tests, and tests flagged as nonnegative. Its combined flag is true only when all three lists are empty. Extra performed tests are included in the validity and result checks.

When to audit screening-record completeness

Use the tool after selecting a test plan and recording results in a consistent naming convention. It can expose incomplete documentation or result/control flags requiring review, while keeping scientific and release decisions outside the record comparison.

Find required tests absent from the performed-test list.
Separate control failures from nonnegative result flags.
Audit additional performed tests as well as the required set.

How to enter test records and evaluate the audit

Enter a nonempty Required tests list of distinct test names.
Enter a nonempty Performed tests list of distinct names, using exact matching names for required tests.
Enter aligned Negative flags and Valid control flags lists; 1 means negative or valid, respectively, and 0 means otherwise.
Run the audit and review all three output lists before interpreting All required valid negative.

The implementation uses exact, case-sensitive string membership without trimming or alias matching. Missing tests are required names absent from performed names. Invalid tests are every performed name with control flag 0. Positive tests are every performed name with negative flag 0, even if its control is invalid.

allRequiredValidNegative = no missingTests AND no invalidTests AND no positiveTests

An additional performed test with a nonnegative result or invalid control makes the combined flag false, even when every required test is valid and negative.

json

{
  "input": {
    "requiredTests": [
      "PCR"
    ],
    "performedTests": [
      "PCR",
      "extra"
    ],
    "negativeFlags": [
      1,
      0
    ],
    "validControlFlags": [
      1,
      1
    ]
  },
  "output": {
    "missingTests": [],
    "invalidTests": [],
    "positiveTests": [
      "extra"
    ],
    "allRequiredValidNegative": false
  }
}

Missing tests follow required-list order; result and validity lists follow performed-list order. Duplicate names, empty required/performed lists, nonbinary flags, and mismatched list lengths produce input errors.

Limitations of a screening-record audit

The tool does not choose required assays, verify sampling or assay sensitivity, interpret raw data, or establish regulatory lot release.
The name positiveTests means negative flag 0 in this representation. It can include an invalid-control result and does not independently confirm replication-competent virus.
Exact name matching requires caller-controlled identifiers. Spelling, case, or surrounding whitespace differences are not reconciled.
No batch identity, chronology, retest policy, assay detection limit, or patient follow-up information is evaluated.

Alternative or Complementary assay-quality reviews

Resolve control validity and assay interpretation using the underlying laboratory records and applicable screening plan. A Ct-delay screen addresses a separate inhibition criterion; per-dose DNA arithmetic checks another quality attribute. Neither establishes replication-competence-screen validity or release authorization.

References

Testing of Retroviral Vector-Based Human Gene Therapy Products for Replication Competent Retrovirus During Product Manufacture and Patient Follow-up — U.S. Food and Drug Administration (2020 guidance)

Similar or alternative tools

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