Diary

A diary is a type of self-administered questionnaire often used to record frequent or contemporaneous events or experiences. In diary surveys, respondents are given the self-administered form and asked to fill in the required information when events occur (event-based diaries) or at specified times or time intervals (time-based diaries). Data from diary studies can be used to make cross-sectional comparisons across people, track an individual over time, or study processes within individuals or families. The main advantages of diary methods are that they allow events to be recorded in their natural setting and, in theory, minimize the delay between the event and the time it is recorded.

Diaries are used in a variety of domains. These include studies of expenditure, nutrition, time use, travel, media exposure, ...