Artículo 4. Availability and Reliability of Data

.15 Data may or may not be readily available to develop expectations for some assertions. For example, to test the completeness assertion, expected sales for some entities might be developed from production statistics or square feet of selling space. For other entities, data relevant to the assertion of completeness of sales may not be readily available, and it may be more effective or efficient to use the details of shipping records to test that assertion. .16 Before using the results obtained from substantive analytical procedures, the auditor should either test the design and operating effectiveness of controls over financial information used in the substantive analytical procedures or perform other procedures to support the completeness and accuracy of the underlying information. The auditor obtains assurance from analytical procedures based upon the consistency of the recorded amounts with expectations developed from data derived from other sources. The reliability of the data used to develop the expectations should be appropriate for the desired level of assurance from the analytical procedure. The auditor should assess the reliability of the data by considering the source of the data and the conditions under which it was gathered, as well as other knowledge the auditor may have about the data. The following factors influence the auditor's consideration of the reliability of data for purposes of achieving audit objectives: Whether the data was obtained from independent sources outside the entity or from sources within the entity Whether sources within the entity were independent of those who are responsible for the amount being audited Whether the data was developed under a reliable system with adequate controls Whether the data was subjected to audit testing in the current or prior year Whether the expectations were developed using data from a variety of sources