Situation
A controlled workbook calculates a finished-product result used by Quality during batch disposition. It has no macros. A new product range and a revised rounding rule are introduced.
Intended Use
Authorized analysts enter approved source values and the workbook calculates a result for qualified Quality review. The workbook does not import raw instrument data or approve the batch.
Failure Scenarios
- A copied formula references the previous row.
- Rounding occurs before the final calculation.
- An analyst uses an uncontrolled local copy.
- A protected formula cell is overwritten through an unlocked range.
Existing Controls and Evidence
The approved template is stored in a controlled location, formula cells are protected, a second analyst verifies the result, and prior known-answer tests are available. Those records do not cover the new product range or revised rounding rule.
Evidence Gaps and Testing Approach
Review every affected formula and reference. Execute independent calculations, exact known-answer cases, values immediately below, at, and above each limit, invalid and blank inputs, unit challenges, protection checks, version identification, save-and-reopen behavior, and controlled-copy retrieval. Record expected and actual values without masking precision.
Validation Conclusion
In this fictional case, a boundary test exposes premature rounding. The workbook is not released until the rule is corrected, independently verified, regression tested, and approved. Absence of macros is not used as the validation decision.
Reassessment Criteria
Reassess formula, lookup, range, rounding, unit, protection, platform, source-data, intended-use, or approved-location changes.