本文探討確信服務相關因素與企業社會責任報告書（CSR 報告書）可信度的關聯，採用兩個實驗並以EMBA 學生為受試者進行研究。研究一結果顯示，確信服務提供者對可信度並無顯著影響。經合理確信的CSR 報告書，其可信度顯著大於經有限確信的報告書。當確信服務提供者為會計師時，經合理確信的CSR 報告書，其可信度顯著大於經有限確信的報告書。研究二結果顯示產業專家對CSR 報告書的可信度有顯著影響。當會計師非為產業專家時，經合理確信的CSR 報告書，其可信度顯著大於經有限確信的報告書。但當會計師為產業專家時，確信水準對可信度無顯著影響。
This paper comprises two experimental studies on the assurance of corporate social responsibility (CSR) reports. The first study examines the effects of assurance providers and assurance levels, and their interaction, on the credibility of CSR reports as perceived by investors. The results indicate that the effect of different assurance providers on CSR report credibility is not significant. However, consistent with expectations, perceived credibility is greater when the assurance level is reasonable than when it is limited. When the assurance providers are auditors, the perceived credibility is higher when the assurance level is reasonable than when it is limited. The second study focuses on the case where the assurance providers are auditors, and examines the effects on perceived credibility of whether the auditors are industry specialists in financial statement assurance, the assurance level, and their interaction. The results indicate that industry specialization has a significant and positive effect. When the auditor is not an industry specialist, the perceived credibility is higher under the condition of reasonable assurance than that of limited assurance.