Hash totals are a control technique used to ensure data integrity during batch processing. A hash total is a calculated value based on the data in a batch. This value is compared to a pre-calculated hash total to confirm that all data has been processed correctly and without alteration. References ISACA CISA Review Manual (27th Edition): Hash totals are discussed within the context of batch processing controls. Other Auditing Resources: Hash totals are a fundamental control technique discussed in various audit and information security publications.