<![CDATA[General Background: Research productivity is an important indicator of university performance and knowledge creation. Specific Background: Despite rising higher education expenditure, enrollment, and institutional expansion in Iraq during 2004–2025, research output growth remained relatively limited. Knowledge Gap: Previous studies have not developed a sector-specific measure of institutional deterioration in Iraqi higher education or examined its asymmetric relationship with research output. Aims: This study analyzes the roles of institutional integrity, credential quality, and public expenditure in determining university research output using a NARDL approach and a newly developed Credential Integrity Erosion Index (CIEI). Results: The findings indicate cointegration among the variables and show that institutional integrity and credential quality have stronger associations with research productivity than public expenditure. Institutional deterioration also generates larger and more persistent output losses than institutional improvement can restore. Novelty: The study introduces the CIEI and applies an asymmetric NARDL framework to Iraqi higher education. Implications: Improving institutional quality and credential verification systems is more critical than increasing expenditure alone for strengthening university research productivity. Highlights: • Institutional integrity and credential quality exhibit stronger relationships with research productivity than funding levels. • Institutional deterioration produces larger and more persistent publication losses than equivalent institutional improvements can recover. • The Credential Integrity Erosion Index offers a sector-specific framework for evaluating academic credential erosion in higher education. Keywords: Institutional Integrity, Credential Quality, Research Productivity, NARDL Model, Higher Education Economics]]>
