Multi-level validation of the ISOmetrics questionnaire based on qualitative and quantitative data obtained from a conventional usability test

Qualitative and quantitative data, collected during a usability evaluation Of two innovative prototypes of a small display touch screen device, have been used to perform a multi-level assessment of the questionnaires used within the trial. The use of different validation methods is depicted and discussed concerning their advantages and disadvantages. The conclusions from the validation study are depicted, revealing that the usage of the ISOmetrics for testing uncommon prototypes may result in insufficient validity of the instrument.