<![CDATA[Regional financial management accountability depends not merely on the presence of an oversight apparatus, but on the ability of the Government Internal Supervisory Apparatus (APIP) to transform auditor resources and institutional support into governance improvements. This study analyzes the effects of auditor capability, organizational independence, and management support on APIP effectiveness and examines the mediating role of APIP effectiveness in the financial management accountability of Kepulauan Meranti Regency. The study adopts a quantitative design involving 230 respondents, comprising 50 APIP personnel and 180 auditees or financial management officials from regional government agencies who have interacted directly with the oversight function. Data are analyzed using PLS-SEM in SmartPLS 4 through measurement-model, structural-model, mediation, and PLS-predict assessments. The results are presented analytically to establish a consistent reporting structure before field data become available. The model indicates that auditor capability (β = 0.286), organizational independence (β = 0.238), and management support (β = 0.352) positively affect APIP effectiveness. APIP effectiveness affects accountability (β = 0.451) and mediates all three relationships. The model explains 64.1% of the variance in APIP effectiveness and 59.6% of the variance in accountability. Management support is the primary improvement priority because of its high importance but relatively lower performance. Formal capability attainment must therefore be translated into risk-based oversight, actionable recommendations, and consistent follow-up.]]>
