STD: BPEC Rule (Bad Positive Expected Control)

Version: v1.0.0 Status: Draft SRS Source: docusaurus/docs/srs/rules/rule-bpec.md Rule Name: BPEC Domain: RULES-BPEC

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Overview

This document specifies tests for the BPEC (Bad Positive Expected Control) rule using decision tables and test vectors. The rule validates positive control wells by detecting unexpected negative classification results and failing such wells with appropriate error codes.

Rule Characteristics:

• Pure business logic (no UI)
• Extends PEC (Positive Expected Control) rule
• Binary classification validation (positive/negative)
• Assay-agnostic logic with multi-assay compatibility
• QC report exclusion behavior

Test Method: TM-API (per Test Plan Section 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-BPEC-001	Validate Positive Control Classification	18	22	100%	None

Totals: 1 REQ, 18 Conditions, 22 Test Vectors, 100% Coverage

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REQ-RULES-BPEC-001: Validate Positive Control Classification

Input Variables

Variable	Type	Valid Values	Description
well.type	string	positive_control, sample, NEC, ...	Well type classification
well.classification	string	positive, negative	Classification result from engine
assay.type	string	Viracor, COVID, HCOVID, PCOVID, QCOVID	Assay type identifier
assay.targets	array	[NCOV1, NCOV3], [NCOV3]	Target genes for COVID assays
error.level	string	well, target	Granularity of failure

Output Variables

Variable	Type	Description
validation.result	string	pass, fail
well.error_code	string?	FAILED_POS_WELL, FAILED_POS_TARGET, or null
well.analysis_blocked	bool	Whether further analysis is prevented
report.westgard_visible	bool	Whether result appears in Westgard/LJ report

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Decision Table: Core Classification Validation

TV	well.type	well.classification	validation.result	error_assigned	Covers
TV-001-001	positive_control	negative	fail	true	AC: Negative classification fails well
TV-001-002	positive_control	positive	pass	false	AC: Positive classification passes BPEC
TV-001-003	sample	negative	N/A	false	AC: Rule only applies to positive controls
TV-001-004	NEC	negative	N/A	false	AC: Rule only applies to positive controls

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Decision Table: Error Code Assignment

TV	error.level	well.classification	well.error_code	Covers
TV-001-005	well	negative	FAILED_POS_WELL	AC: Well-level failure code
TV-001-006	target	negative	FAILED_POS_TARGET	AC: Target-level failure code
TV-001-007	well	positive	null	AC: No error on pass
TV-001-008	target	positive	null	AC: No error on pass

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Decision Table: Analysis Blocking

TV	validation.result	well.analysis_blocked	Covers
TV-001-009	fail	true	AC: Failure prevents further analysis
TV-001-010	pass	false	AC: Pass allows rule chain to continue

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Decision Table: Viracor Assay Compatibility

TV	assay.type	well.classification	validation.result	Covers
TV-001-011	Viracor	negative	fail	AC: Viracor negative fails
TV-001-012	Viracor	positive	pass	AC: Viracor positive passes

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Decision Table: COVID Assay Compatibility (NCOV1 + NCOV3)

TV	assay.type	assay.targets	well.classification	validation.result	Covers
TV-001-013	COVID	[NCOV1, NCOV3]	negative	fail	AC: COVID dual-target negative fails
TV-001-014	COVID	[NCOV1, NCOV3]	positive	pass	AC: COVID dual-target positive passes
TV-001-015	HCOVID	[NCOV1, NCOV3]	negative	fail	AC: HCOVID dual-target negative fails
TV-001-016	PCOVID	[NCOV1, NCOV3]	negative	fail	AC: PCOVID dual-target negative fails
TV-001-017	QCOVID	[NCOV1, NCOV3]	negative	fail	AC: QCOVID dual-target negative fails

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Decision Table: COVID Assay Compatibility (NCOV3 Only)

TV	assay.type	assay.targets	well.classification	validation.result	Covers
TV-001-018	COVID	[NCOV3]	negative	fail	AC: COVID NCOV3-only negative fails
TV-001-019	HCOVID	[NCOV3]	negative	fail	AC: HCOVID NCOV3-only negative fails
TV-001-020	PCOVID	[NCOV3]	negative	fail	AC: PCOVID NCOV3-only negative fails
TV-001-021	QCOVID	[NCOV3]	negative	fail	AC: QCOVID NCOV3-only negative fails

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Decision Table: Westgard/LJ Report Exclusion

TV	validation.result	report.westgard_visible	standard_results_visible	Covers
TV-001-022	fail	false	true	AC: BPEC failures excluded from Westgard/LJ but visible in standard results

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Test File Locations

Requirement	Test File	Method	Automation Status
REQ-RULES-BPEC-001	tests/Unit/Rules/BpecRuleTest.php	TM-API	Automated

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Traceability to Existing Tests

Requirement	Jira Tests	Status
REQ-RULES-BPEC-001	BT-1360, BT-1575, BT-1576, BT-1577, BT-1578, BT-1579, BT-1580, BT-1581, BT-1582	Existing

Jira Test Mapping

Jira Ticket	Test Vectors Covered	Description
BT-1360	TV-001-011, TV-001-012	Viracor assay compatibility
BT-1575	TV-001-013, TV-001-014	COVID dual-target (NCOV1+NCOV3)
BT-1576	TV-001-015	HCOVID dual-target (NCOV1+NCOV3)
BT-1577	TV-001-016	PCOVID dual-target (NCOV1+NCOV3)
BT-1578	TV-001-017	QCOVID dual-target (NCOV1+NCOV3)
BT-1579	TV-001-018	COVID NCOV3-only
BT-1580	TV-001-019	HCOVID NCOV3-only
BT-1581	TV-001-020	PCOVID NCOV3-only
BT-1582	TV-001-021	QCOVID NCOV3-only

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Gap Analysis

Identified Gaps

Gap	Requirement	Description	Priority	Owner
None	-	All acceptance criteria covered by test vectors	-	-

Coverage Notes

• Core classification logic (TV-001-001 through TV-001-004) exercises the fundamental pass/fail decision
• Error code assignment (TV-001-005 through TV-001-008) verifies both well-level and target-level error handling
• Assay compatibility tests (TV-001-011 through TV-001-021) ensure rule works across all supported assay configurations
• Report exclusion (TV-001-022) verifies the QC reporting constraint