The method consists of three phases: organizing, conducting and evaluating interviews.
Organization: prepare the question, determine the subjects, select the devices.
Execution: Pay attention to the correct questioning technique when interviewing. Ask open questions (it's not about products and details, it's about behaviors). Do not ask leading questions. The interview is a conversation and not an interrogation. If you take notes, you can ask questions that arise later and must not interrupt the subject.
Evaluation: The evaluation (transcription) of audio recordings can be outsourced. The transcripts are combed for activities. Transfer activities to an outline editor (such as OmniOutliner), group and remove duplicates. Then the mental model diagram is created (for example with OmniGraffle). Higher-level activities are separated into individual sections by vertical lines (the so-called mental spaces). These towers group several small activities. At the end the diagram will be printed out to be discussed in the group.
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