Audit Quality and the Reliability of Sustainable Development Goals-Related Disclosures in Nigeria

The integrity of corporate sustainability reporting has emerged as a pivotal concern for investors, regulators, and multilateral institutions seeking to align capital allocation with the United Nations' 2030 Agenda for Sustainable Development. This study examines the effect of audit quality on the reliability of Sustainable Development Goals (SDG)-related disclosures among listed Nigerian firms. Employing an ex-post facto research design, the study draws on a balanced panel dataset of 148 listed firms on the Nigerian Exchange Group (NGX) over the period 2010 to 2024, yielding 2,220 firm-year observations. SDG disclosure reliability is operationalised using a content analysis-based index, while audit quality is proxied by Big 4 auditor engagement supplemented by log-transformed audit fees. The study controls for firm size, profitability, leverage, growth opportunities, firm age, and liquidity. Panel regression techniques, including pooled ordinary least squares, fixed effects model, random effects model, system generalised method of moments, and feasible generalised least squares, are employed, with robustness verified through a comprehensive suite of post-estimation diagnostics. Results reveal that audit quality exerts a significant positive effect on SDG disclosure reliability, underscoring the indispensable role of independent, high-quality audit assurance in curbing greenwashing and SDG-washing. The findings carry profound implications for standard-setters, corporate boards, and sustainability investors operating within Africa's largest economy.