Audit evidence sufficiency is based on its appropriateness, adequate quantity, relevance, reliability, and neutrality, ensuring it provides a strong foundation for the auditor's conclusions. Audit evidence is generally considered sufficient when it is appropriate, there is enough of it to support well-founded conclusions, and it is relevant, reliable, and free from bias.
When gathering audit evidence, the significant factors include the appropriateness of the evidence, its relevance to the matter at hand, the reliability of the source, and the absence of bias. Appropriate audit evidence must align with the auditing objective and should support the auditor's conclusions. Quantity is important, as there must be enough evidence to underpin sound judgment. However, random sampling alone doesn't guarantee sufficiency; it's the quality and the convergence of information from different sources that bolsters the support for an audit finding. The auditor must also consider potential biases in the evidence and evaluate whether the evidence truly supports the assertions made in the financial statements.
Ultimately, sufficient audit evidence must meet specific quality criteria, including appropriateness and lack of bias, in addition to quantity to form a solid base for the auditor's judgment.