XVI Our objectives are to obtain reasonable assurance as to whether the EDF accounts are free from material misstatement and the underlying transactions are legal and regular, and to provide, on the basis of our audit, the European Parliament and the Council with a statement of assurance as to the reliability of the accounts and the legality and regularity of the underlying transactions. Reasonable assurance is a high level of assurance, but it is not a guarantee that the audit has necessarily detected all instances of a material misstatement or non-compliance that may exist. These can arise from fraud or error and are considered material if, individually or in the aggregate, they could reasonably be expected to influence any economic decisions taken on the basis of these EDF accounts. XVII As part of an audit in accordance with ISAs and ISSAIs, we exercise professional judgement and maintain professional scepticism throughout the audit. We also: — Identify and assess the risks of material misstatement of the EDF accounts and of material non-compliance of the underlying transactions with the requirements of the EDF legal framework, whether due to fraud or error. We design and perform audit procedures responsive to those risks and obtain audit evidence that is sufficient and appropriate to provide a basis for our opinion. Instances of material misstatement or non-compliance resulting from fraud are more difficult to detect than those resulting from error, as fraud may involve collusion, forgery, intentional omissions, misrepresentations, or the override of internal control. Consequently, there is a greater risk of such instances not being detected. — Obtain an understanding of internal control relevant to the audit in order to design appropriate audit procedures, but not for the purpose of expressing an opinion on the effectiveness of the internal control. — Evaluate the appropriateness of the accounting policies used by management and the reasonableness of management’s accounting estimates and related disclosures. — Conclude as to the appropriateness of management’s use of the going concern basis of accounting and, based on the audit evidence obtained, as to whether material uncertainty exists owing to events or conditions that may cast significant doubt on the EDFs’ ability to continue as a going concern. If we conclude that such material uncertainty exists, we are required to draw attention in our report to the related disclosures in the EDF accounts or, if these disclosures are inadequate, to modify our opinion. Our conclusions are based on the audit evidence obtained up to the date of our report. However, future events or conditions may cause the entity to cease to continue as a going concern. — Evaluate the overall presentation, structure and content of the annual accounts, including all disclosures, and assess whether the annual accounts fairly represent the underlying transactions and events. XVIII We communicate with management regarding, among other matters, the planned scope and timing of the audit and significant audit findings, including findings of any significant deficiencies in internal control. XIX For revenue, we examine all contributions from Member States and a sample of other types of revenue transactions. XX For expenditure, we examine payment transactions once expenditure has been incurred, recorded and accepted. This examination covers all categories of payments (other than advances) at the point they are made. Advance payments are examined once the recipient of funds has provided evidence of their proper use and the institution or body has accepted that evidence by clearing the advance payment, which might not happen until a subsequent year. XXI Of the matters discussed with the Commission, we determine which were of most significance in the audit of the EDF accounts and are therefore the key audit matters for the current period. We describe these matters in our report unless law or regulation precludes public disclosure or, as happens extremely rarely, we determine that a matter should not be communicated in our report because the adverse consequences of doing so would reasonably be expected to outweigh any public interest benefits.