Qualitative data
Research projects aiming at measuring activity in terms of their quality, rather than quantity, use methods such as focus groups, diaries and (most usually) semi-structured interviews. Qualitative data may be in some cases confidential or difficult to contextualise, but this does not prevent it being collected, preserved and re-used.
As a result, an ever-growing amount of qualitative research data is being deposited with national data centres and institutional repositories. Most often, this is available as text transcriptions of the original interviews. However, in many cases the original audio or video from such projects is also being made available.