STD: WC Rule (Cross Talk) - DEPRECATED

DEPRECATED

This rule has been deprecated as of 2026-02-02.

The WC (Cross-Talk) rule was never implemented in the application codebase (no WCRule.php exists). This test specification is retained for historical reference only. No test coverage is required.

Version: v1.0.0 Status: Draft DEPRECATED SRS Source: docusaurus/docs/rules/rule-wc.md Rule Name: WC (Cross Talk) Domain: RULES-WC

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Overview

This document specifies tests for the WC (Cross Talk) rule using decision tables and test vectors. The rule detects cross-talk conditions in PCR wells where multiple non-IC targets test positive, marking affected samples for re-extraction.

Rule Characteristics:

• Pure business logic (no UI)
• Assay-specific (HSV, HTLV only)
• Sample-type filtering (patient samples only)
• Extraction status filtering (first extraction only)
• Target type filtering (non-IC targets only)

Test Method: TM-API (per Test Plan §3.3 - Rules use automated API tests)

Verification Approach: Rule verification is performed using data-driven test vectors. Each row in a decision table represents a complete verification scenario with defined inputs and expected outputs. This format enables exhaustive condition coverage while remaining concise and auditable.

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Coverage Summary

REQ ID	Title	Conditions	Test Vectors	Coverage	Gaps
REQ-RULES-WC-001	Cross-Talk Detection	7	18	100%	None

Totals: 1 REQ, 7 Conditions, 18 Test Vectors, 100% Coverage

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REQ-RULES-WC-001: Cross-Talk Detection

Input Variables

Variable	Type	Valid Values	Description
assay_type	string	HSV, HTLV, Other	Assay type from kit configuration
sample_type	string	Patient, Control	Sample classification (patient vs control)
extraction_status	string	First, Re-extraction	Whether this is first extraction or re-extraction
positive_non_ic_count	int	0, 1, 2+	Count of positive non-IC targets in well
ic_positive	bool	true, false	Whether IC (Internal Control) target is positive
sample_type_determinable	bool	true, false	Whether sample type can be determined
extraction_status_determinable	bool	true, false	Whether extraction status can be determined

Output Variables

Variable	Type	Description
lims_result	string?	LIMS export result code (RXT when triggered, null otherwise)
warning_generated	bool	Whether a well warning was generated
warning_message	string?	Warning message content when generated
rule_applied	bool	Whether the rule was evaluated (vs skipped)

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Decision Table: Assay Type Filtering

Tests that the rule only applies to HSV and HTLV assays.

TV	assay_type	sample_type	extraction_status	positive_non_ic_count	rule_applied	lims_result	Covers
TV-001-001	HSV	Patient	First	2	true	RXT	AC: HSV assay triggers rule
TV-001-002	HTLV	Patient	First	2	true	RXT	AC: HTLV assay triggers rule
TV-001-003	Other	Patient	First	2	false	null	AC: Non-HSV/HTLV assays excluded

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Decision Table: Sample Type Filtering

Tests that the rule only applies to patient samples.

TV	assay_type	sample_type	extraction_status	positive_non_ic_count	rule_applied	lims_result	Covers
TV-001-004	HSV	Patient	First	2	true	RXT	AC: Patient samples processed
TV-001-005	HSV	Control	First	2	false	null	AC: Control samples excluded

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Decision Table: Extraction Status Filtering

Tests that the rule only applies to first-time extraction.

TV	assay_type	sample_type	extraction_status	positive_non_ic_count	rule_applied	lims_result	Covers
TV-001-006	HSV	Patient	First	2	true	RXT	AC: First extraction processed
TV-001-007	HSV	Patient	Re-extraction	2	false	null	AC: Re-extractions excluded

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Decision Table: Positive Target Count Threshold

Tests the threshold condition (more than 1 positive non-IC target required).

TV	assay_type	sample_type	extraction_status	positive_non_ic_count	rule_applied	lims_result	warning_generated	Covers
TV-001-008	HSV	Patient	First	0	true	null	false	AC: Zero positives - no trigger
TV-001-009	HSV	Patient	First	1	true	null	false	AC: One positive - no trigger
TV-001-010	HSV	Patient	First	2	true	RXT	true	AC: Two positives - trigger
TV-001-011	HSV	Patient	First	3	true	RXT	true	AC: Three+ positives - trigger

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Decision Table: IC Target Exclusion

Tests that IC (Internal Control) targets are excluded from the positive count.

TV	positive_non_ic_count	ic_positive	effective_count	lims_result	Covers
TV-001-012	1	false	1	null	AC: Single non-IC, IC negative - no trigger
TV-001-013	1	true	1	null	AC: Single non-IC, IC positive - IC excluded from count
TV-001-014	2	false	2	RXT	AC: Two non-IC, IC negative - trigger
TV-001-015	2	true	2	RXT	AC: Two non-IC, IC positive - IC excluded, still triggers

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Decision Table: Warning Message Generation

Tests the warning message format when cross-talk is detected.

TV	target_a	target_b	expected_warning	Covers
TV-001-016	HSV-1	HSV-2	"HSV-1 and HSV-2 are both positive. Re-extract sample"	AC: Warning format with target names

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Decision Table: Error Handling (Skip Conditions)

Tests error handling when required data is undeterminable.

TV	sample_type_determinable	extraction_status_determinable	assay_type	rule_applied	action	Covers
TV-001-017	false	true	HSV	false	Skip + Log	AC: Sample type undeterminable - skip
TV-001-018	true	false	HSV	false	Skip + Log	AC: Extraction status undeterminable - skip

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Test File Locations

Requirement	Test File	Automation Status
REQ-RULES-WC-001	tests/Unit/Rules/WCRuleTest.php	Automated

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Traceability to Existing Tests

Requirement	Jira Tests	Status
REQ-RULES-WC-001	—	Gap

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Gap Analysis

Identified Gaps

Gap	Requirement	Description	Priority	Owner
GAP-001	REQ-RULES-WC-001	No Behat tests cover WC (cross-talk) rule; all 18 TVs are gaps	High	TBD

Note: WC rule is specific to HSV/HTLV assays detecting multi-positive non-IC targets. Existing tests (BT-5576, BT-5842, BT-5183, BT-5837, BT-5300) test other rules, not WC.

Coverage Verification

All acceptance criteria from REQ-RULES-WC-001 are traced to test vectors:

Acceptance Criteria	Test Vectors
Multiple non-IC positive → RXT	TV-001-010, TV-001-011
HSV/HTLV assays only	TV-001-001, TV-001-002, TV-001-003
First extraction only	TV-001-006, TV-001-007
Patient samples only	TV-001-004, TV-001-005
IC targets excluded	TV-001-012 through TV-001-015
Zero positives no trigger	TV-001-008
One positive no trigger	TV-001-009
Warning message format	TV-001-016
Sample type undeterminable handling	TV-001-017
Extraction status undeterminable handling	TV-001-018