Development of an Internal Control and Internal Audit Model to Strengthen Good Governance and Prevent Corruption in Public and Private Sector Organizations in Northeastern Thailand

Abstract

This study aimed to (1) examine the current state, problems, and factors influencing the effectiveness of internal control and internal
audit systems and their relationship to good governance and corruption prevention; (2) develop and test an integrated model aligned with
international standards and suitable for the Northeastern Thailand context; and (3) formulate policy recommendations for sustainable
implementation. A Mixed Methods Research design (Explanatory Sequential Design) integrated with Research and Development (R&D) was
employed across four phases. A quantitative sample of 490 respondents was drawn using Yamane's formula from public and private sector
personnel across 20 Northeastern provinces, with proportionate stratified random sampling. Data were collected via a 5-point Likert scale
questionnaire and analyzed using descriptive statistics and Structural Equation Modeling (SEM/AMOS). Qualitative data were gathered
through 32 in-depth interviews and 5 focus group discussions (n = 74), with model validation by 11 experts and pilot implementation at 7
organizations over 8 months. Results revealed that organizations had moderate-level internal control (M = 3.24, SD = 0.78), with risk
assessment (M = 2.96) and monitoring activities (M = 2.88) as primary weaknesses. SEM analysis identified top management support as the
most influential factor (β = 0.34), followed by staff competency (β = 0.26–0.32), IT systems (β = 0.18–0.24), organizational structure (β =
0.22), and organizational culture (β = 0.20). Internal control effectiveness positively influenced good governance (β = 0.42) and negatively
influenced fraud risk (total effect β = −0.50). The IICIAM-NETH model—comprising six components and validated with an IOC index of
0.86—demonstrated significant improvements after implementation: internal control completeness increased 29.6%, internal audit quality
31.2%, governance levels 22.2%, and fraud risk decreased 34.2% (p < .001 for all). The model, integrating COSO 2013 and IIA IPPF standards
with local context, proved effective in enhancing governance and reducing corruption risk across both sectors.