The SDDOLZ application’s primary task is to schedule when to send out test letters in order to monitor delivery quality. The application lists the people who receive the test letters. The application can then calculate statistics for delivery times by region using these test letters.
Česká pošta is one of the largest employers in the Czech Republic. The application for monitoring the delivery time on letters (SDD OLZ) is in operation at all respondents listed in the application. These respondents always fill out the records in the SDD OLZ application after delivery.