Which interview style is useful for exploring aspects not addressed by structured tools?

Semi-structured interviews are particularly useful for exploring aspects that might not be adequately addressed by structured tools because they blend the benefits of both structured and unstructured approaches. In a semi-structured interview, the interviewer has a set of predetermined questions and topics to cover but also has the flexibility to explore responses in greater depth. This flexibility allows the interviewer to probe further on responses, follow interesting leads, and adapt the flow of the conversation based on the interviewee's answers.

This approach facilitates a more in-depth understanding of the interviewee's perspective, capturing nuances and insights that rigid, structured formats often overlook. Unlike structured interviews that typically follow a strict question-and-answer format, or informal conversations that lack focus and direction, semi-structured interviews encourage a richer dialogue, making them particularly effective for gathering qualitative data and exploring complex issues.

Open-ended interviews and informal conversations have their merits but do not provide the same balance between structure and flexibility that semi-structured interviews offer, while survey-based assessments are generally focused on quantitative data with limited room for in-depth discussion.