Beyond Crude IVF KPIs: A Stepwise Framework for Denominator-Aware and Case-Mix-Adjusted Performance Interpretation

Performance monitoring is central to assisted reproductive technology (ART), yet crude in vitro fertilization (IVF) key performance indicators (KPIs) are strongly influenced by denominator selection, patient prognosis, treatment strategy, case mix and sample size. This opinion article examines the methodological limitations of conventional IVF KPIs and proposes a denominator-aware, step-specific and case-mix-adjusted framework for their interpretation. Concepts from international KPI consensus frameworks, outcome-reporting literature, clinic-comparison methods and reproductive prediction models were integrated into a conceptual quality management framework. IVF was treated as a sequence of linked biological and clinical transitions. The framework links five elements: specification of the performance question, validation of the denominator, estimation of expected outcomes from temporally appropriate patient- and cycle-level factors, comparison of observed and expected outcomes, and uncertainty-aware interpretation of step-specific process patterns. A hypothetical worked example demonstrates stage-specific crude rates, expected events and observed/expected (O/E) ratios. The process-pattern labels are conceptual descriptors rather than validated classifications, and signals require multidisciplinary review. The framework has the potential to support more context-aware and biologically coherent performance review. It should complement, not replace, conventional KPIs; whether it improves fairness, transparency or quality management remains to be established in prospective multicentre validation.