Formation of a Methodological Basis for Performance Auditing Based on the International Practices

Amid the complexity of business processes, audit has transformed from a tool for retrospective financial control into a mechanism for assessing operational efficiency and supporting the strategic development of enterprises. At the same time, performance audit in the private sector remains insufficiently standardized due to the lack of a unified regulatory and methodological framework, which limits the reproducibility of audit results and largely determines their dependence on the auditor’s professional judgment. The article aims to analyze successful international cases of applying performance audits in the private sector and to identify key elements for developing a universal audit methodological framework to create added value in private-sector enterprises. The theoretical basis of the study is the concepts of operational audit and performance audit, and the principles of the “3E” model (economy, productivity, effectiveness), which were used as an analytical framework for evaluating practical cases. The empirical basis of the study covers international practical cases of operational and performance audits published in open professional sources. The research methodology consists of methods of analysis and synthesis, logical generalization, comparison, classification, and abstract-logical modeling. The researchers systematized practical cases in three main areas: optimization of logistics processes, improvement of production activities, and evaluation of internal control systems. The results of the study show that financial losses are mostly a consequence of hidden operational shortcomings, in particular, inefficient organization of business processes, insufficient effectiveness of control procedures, delays in information flows, and a low level of human capital development. The article proposes a universal methodological matrix for efficiency audits, built on four interrelated areas: control, processes, response speed, and personnel. The use of the proposed approach ensures the systematization of the search for the causes of operational inefficiency, increases the reproducibility of audit procedures, and helps managers identify internal reserves to increase the efficiency and sustainability of enterprises. In addition, the study showed that traditional financial accounting and financial reporting data are an insufficient information base for performance auditing due to their retrospective and aggregated nature, which necessitates the use of operational and non-financial indicators.