The audit report should be substantiated, in order to give a meaningful account of the activities undertaken and the conclusions reached. It should help inform, and where appropriate suggest improvements to the measures taken by the providers of the very large online platform and of the very large online search engine to comply with their obligations under this Regulation. The audit report should be transmitted to the Digital Services Coordinator of establishment, the Commission and the Board following the receipt of the audit report. Providers should also transmit upon completion without undue delay each of the reports on the risk assessment and the mitigation measures, as well as the audit implementation report of the provider of the very large online platform or of the very large online search engine showing how they have addressed the audit’s recommendations. The audit report should include an audit opinion based on the conclusions drawn from the audit evidence obtained. A ‘positive opinion’ should be given where all evidence shows that the provider of the very large online platform or of the very large online search engine complies with the obligations laid down by this Regulation or, where applicable, any commitments it has undertaken pursuant to a code of conduct or crisis protocol, in particular by identifying, evaluating and mitigating the systemic risks posed by its system and services. A ‘positive opinion’ should be accompanied by comments where the auditor wishes to include remarks that do not have a substantial effect on the outcome of the audit. A ‘negative opinion’ should be given where the auditor considers that the provider of the very large online platform or of the very large online search engine does not comply with this Regulation or the commitments undertaken. Where the audit opinion could not reach a conclusion for specific elements that fall within the scope of the audit, an explanation of reasons for the failure to reach such a conclusion should be included in the audit opinion. Where applicable, the report should include a description of specific elements that could not be audited, and an explanation of why these could not be audited.