Reframing layered process audits as risk-based manufacturing process audits: A quality management systems case study

Organizations certified to IATF 16949 frequently operate parallel Layered Process Audits (LPAs) and Manufacturing Process Audits (MPAs), increasing audit workload without proportionate gains in risk detection. LPAs are widely used to reinforce standard work yet often treated as checklist-driven compliance tools rather than process assurance mechanisms. This study addresses a gap in the literature: the absence of a governance-based framework enabling LPAs to fulfill core MPA intent without duplicating audit infrastructure. The study proposes and applies a risk-based audit consolidation framework grounded in PDCA, risk-based thinking, organizational reliability theory, and governance through management review, operationalized using an audit sufficiency assessment table and three deployment models, and states three propositions. Application at a single IATF 16949-certified automotive-component manufacturing facility was associated with a 61% relative reduction in the normalized repeat-finding index, together with earlier detection of process deviation and reduced audit redundancy. Managerial implications are provided as a decision-support view and implementation roadmap for selecting audit depth, prioritizing high-risk processes, and monitoring auditor effectiveness. The findings suggest quality managers should prioritize audit design rigor and risk-based governance over frequency or label, and that, where certification and customer-specific requirements permit, LPA consolidation offers a pathway to stronger QMS effectiveness and organizational learning.