Table 1. Usability problems in the UAF planning phase with their severity and potential effect on task outcome.

ID No.	Level 1	Level 2	Level 3	Level 4	Description of usability problem	No.1	Severity	Identifying potential outcomes2
1	Planning	Users model of the system	Users ability to determine what to do first		It is not immediately clear for the user which diagnosis has to be chosen in case of urosepsis (two possible pathways). The first information input that had to be entered manually by the user is the diagnosis. This is done by selecting one of the diagnosis in a drop down menu. For the diagnosis urosepsis the user has two possible pathways, namely the user can select sepsis, with sepsis focus urogenital tract or high urinary tract infection.	3	2	None (both pathways same result)
2		Goal decomposition	Users ability to determine what to do next		User has to answer if patient has an aspiration pneumonia. Because user doesn’t know user chooses the answer ‘no’. The option ‘unknown’ does not exist in the system.	1	0	Wrong antibiotic
3		Goal decomposition	Users ability to determine what to do next		Information is missing about what has to be filled in when the existence of neutropenia is unknown.	2	2	Wrong antibiotic
4		Users knowledge of system state, modalities.			When entering a new patient identification number nothing happens.	1	2	None

¹The number of usability problems with the same classification path, in the interaction of different or the same user with the system.

²The mentioned outcomes are potential and did not have to occur.