- for smartphone assisted coaching: Data entry by users (both the patient and the dietitian) are always validated used predefined patterns and range checks. If for any reason something goes wrong the user is informed about the unsuccessful data entry and might be (depending on the severity of the error) forced to login to the respective system again to assert that no inconsistent state is displayed to the user. Data is kept consistent by validity checks defined by dietitians and is stored in a highly structured and consistency-constrained database hosted by a medical infrastructure provider.