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When to Use This Guide

After running traceability coverage checks (via nxLinkCoverage macro on space dashboards), you’ll see coverage percentages and gap counts. When coverage is below target thresholds (typically <80% for customer→system, <100% for requirement→test), use this guide to systematically resolve gaps.

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Step 1: Access Gap Query Results

From any space dashboard coverage bar (Requirements, Design, Testing), click the gap count link (e.g., “12 uncovered”) to open the Work Items Tracker filtered to uncovered items. Example gap queries:
  • Customer Reqs without System Reqs: type:customerRequirement AND NOT backlinkedWorkItems:refines=TA*
  • System Reqs without Test Cases: type:sysReq AND NOT backlinkedWorkItems:verifies=TA*
  • Design Reqs without System Reqs: type:desReq AND NOT linkedWorkItems:refines=TA*
The Tracker shows all work items matching the gap query, sorted by ID.

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Step 2: Triage Uncovered Items

Review each uncovered item and determine the root cause:
Gap TypeAction Required
Valid gap — item should have linkCreate missing link (Step 3)
Invalid scope — item out of scope for this projectAdd outOfScope tag or archive item
Duplicate item — redundant with existing itemMerge or delete duplicate
Wrong item type — misclassified work itemChange work item type via form
Parent-level item — intentionally has no direct link (children do)Document in Description field with “Covered by child items” note
Creating incorrect traceability links to artificially inflate coverage metrics violates ISO 26262 audit requirements. If an item genuinely has no upstream or downstream artifact, investigate whether it should exist or be reclassified.

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Option A: Single Item — Use Work Item Form

  1. Open the uncovered work item from the Tracker
  2. Navigate to the Links tab in the work item form
  3. Click Add Link and select the appropriate link role:
    • refines — for requirement decomposition (customer→system, system→design)
    • verifies — for test case to requirement verification
    • validates — for validation test to user need/customer requirement
    • assesses — for characteristic to failure mode
  4. Search for the target work item by ID or title
  5. Click OK and Save the work item

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Option B: Bulk Linking — Use PowerSheet RTM Views

For fixing multiple gaps in the same traceability chain, use PowerSheet configurations:
  • Whole RTM Sheet — shows all four requirement tiers (Customer/System/Subsystem/Design) + Verification Tests
  • Component RTM Sheet — shows Subsystem/Design requirements + upstream System requirements
  • Verification Sheets — show Requirements + linked Test Cases in split view
Bulk linking workflow:
  1. Open the relevant PowerSheet from Home Dashboard → PowerSheets section
  2. Locate the uncovered requirement row (missing linked entity in expansion column)
  3. Click the entity factory icon ➕ in the target column
  4. Select existing work item from picker dialog OR create new inline work item
  5. PowerSheet auto-creates the link with correct link role based on RTM model configuration
  6. Repeat for all gaps visible in the current PowerSheet filter
Apply a PowerSheet filter to show only rows where a specific column (e.g., linked test cases) is empty. This isolates all gap items in one view. Filter syntax: configure saved view with “Has no links” condition on the relationship column.

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Step 4: Handle Complex Multi-Hop Gaps

For SC/CC Design Requirements → Failure Modes coverage (via characteristics), the traceability path requires two hops: Gap resolution algorithm:
  1. Identify uncovered SC/CC Design Requirement from gap query: type:desReq AND classification.KEY:(sc cc)
  2. Check if requirement has back-linked Characteristic via refines role
    • No characteristic? → Create Characteristic work item, link to Design Req with refines
  3. Check if linked Characteristic has back-linked Failure Mode via assesses role
    • No failure mode? → Navigate to appropriate FMEA Risksheet, add Failure Mode row, link to Characteristic
  4. Verify both link roles are correctly set (not reversed: Characteristic refines Design Req, Failure Mode assesses Characteristic)
Multi-hop coverage checks traverse links in specific directions. For SC/CC coverage: Design Req ← refines ← Characteristic ← assesses ← Failure Mode. If you create links in the wrong direction (e.g., Design Req refines Characteristic), the coverage algorithm won’t detect the chain.

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Step 5: Re-Check Coverage Metrics

After creating missing links:
  1. Return to the space dashboard (Requirements, Design, Testing)
  2. Refresh the page to re-execute coverage macros (F5 or Ctrl+R)
  3. Verify the coverage percentage increased and gap count decreased
  4. If gaps remain, repeat Steps 2-4 for remaining uncovered items
Expected outcomes:
  • Customer→System Reqs: ≥80% (some customer requirements may be out of scope)
  • System→Design Reqs: ≥80% (system-level requirements may not decompose to all components)
  • Requirements→Test Cases: 100% (all safety-classified requirements must be verified per ISO 26262)
  • SC/CC Design Reqs→Failure Modes: 100% (all special characteristics must have FMEA coverage per AIAG-VDA)

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Verification

You should now see:
  • Reduced gap counts on space dashboard coverage bars
  • Previously uncovered items no longer appearing in gap query Tracker views
  • Green coverage bars (≥80%) instead of yellow (<80%) or red (<50%)
  • Traceability Report showing complete bidirectional chains for audited items

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See Also