Final answer:
An interview guide is instrumental in semi-structured interviews to collect comparable data while allowing depth in responses, ensuring relevance to research questions.
Step-by-step explanation:
It is helpful to prepare an interview guide before conducting semi-structured interviews because it ensures that the data from different interviewees will be comparable and directly relevant to your research questions. An interview guide helps maintain a balance between the structured approach of collecting comparable information and the flexibility of allowing for additional insights. This approach fosters a systematic collection of data while providing space for interviewees to explore topics more deeply than they might with a more formal interview structure, resulting in rich and nuanced data.