Equity at the margins of prospective payment in China: a comparative policy text analysis of special case negotiation rules

Special case negotiation is one way prospective payment systems deal with cases that fall outside routine grouping rules. Yet these arrangements are often written as technical details rather than treated as part of the governance structure itself. When a province uses one overall framework but municipalities write their own operating rules, differences across cities can translate into uneven access and inconsistent handling of disputes. We analysed policy documents on special case negotiation from 18 municipalities in Province A. Using a governance and equity lens, we developed a codebook with four modules, minimum boundaries, discretion constraints, administrative friction, and intra-provincial consistency and equity, operationalised into 20 binary indicators. Indicators were coded as 1 only when an explicit and verifiable operational rule was stated, with no inference for missing text. We computed a Policy Modeling Consistency (PMC) total score as the mean of 20 indicators and module scores as within-module averages. We then applied transparent rule-based criteria to build a municipal policy typology and derived a two-tier minimum clause package for provincial standardisation. Municipal policies showed pronounced divergence in textual specification of institutional design. The mean PMC total score was 0.42 (range 0.15 to 0.65). Minimum boundaries exhibited the widest spread (0.20 to 1.00), while discretion constraints and consistency and equity often lacked a shared minimum baseline (ranges 0.00 to 0.60 and 0.00 to 0.80, respectively). Divergence clustered around verifiable cap and threshold definitions, structured treatment of new technologies, proceduralisation of expert review (selection, recusal, arbitration, decision rules), appeal pathways and finality boundaries, and within-province cross-area responsibility rules. The typology identified four types with distinct governance orientations, including a consistency-oriented group, boundary-clear but consistency-limited designs, low-explicitness baseline texts, and transitional profiles. Within one provincial framework, special case negotiation rules vary materially in formal explicitness and procedural traceability. Our findings suggest that provincial standardisation may be most useful when it targets a small set of aligned key nodes, especially verifiable entry boundaries, core review procedures, appeal finality, and cross-area responsibility, while leaving room for bounded local adaptation.