When Interpretations Fail the Test: A Diagnostic Protocol for Claims about the Quantum Measurement Problem

Abstract Persistent disagreement among interpretations of quantum mechanics is widely acknowledged, yet there is no standard method for assessing which interpretive claims satisfy the structural preconditions of physical description and which remain incomplete. We introduce a claim-level diagnostic protocol comprising six applicability conditions (A1–A6) that classifies interpretive statements without adjudicating their truth. The protocol outputs standardised verdicts—PASS, OPEN, or Limit of Applicability (LoA)—together with specific reformulation directives for each deficit. We apply the protocol systematically to six major interpretations: Copenhagen, Many Worlds, QBism, Objective Collapse, Bohmian Mechanics, and Relational Quantum Mechanics. Three principal results emerge. First, no interpretation achieves an unrestricted PASS across all six conditions—the measurement problem is genuinely open, not merely contested. Second, deficit patterns organise into systematic trade-offs between formal consistency, posit commitments, and empirical accessibility. Third, and most consequentially, the protocol reaches the limit of its own presuppositions when applied to QBism, yielding a TYPE-SHIFT verdict that raises the question whether certain interpretive positions constitute physical claims or rationality-theoretic frameworks employing physical formalism.