---
name: diary-study
description: Use when asked to run a diary study — recruitment, guidelines, diary keeping, data collection, analysis, reporting — a longitudinal qualitative research method for capturing experiences, behaviors, and thoughts as they unfold over time, from participants' own ongoing records.
---

# Diary Study

A diary study is a research method for collecting qualitative data about
individuals' experiences, behaviors, and thoughts over a specific period
of time — participants keep a record, often a diary or journal, of their
activities, emotions, and other relevant information. Diary studies are
particularly useful for phenomena that unfold over time, or for
exploring people's thoughts and experiences within their own context,
rather than in an artificial lab or interview setting.

## General overview

- **Recruitment** — identify and recruit participants willing to keep a
  diary and provide regular entries, with participation scope depending
  on the research goals and available resources.
- **Guidelines** — provide instructions on what to record: specific
  events, activities, emotions, or other aspects relevant to the study.
- **Diary keeping** — participants record entries, often daily or
  weekly depending on the study's duration, in written, audio, or
  multimedia form.
- **Data collection** — collect the diaries and associated materials,
  potentially with additional interviews or surveys to gather more
  context or clarify diary entries.
- **Data analysis** — analyze entries and other collected data with
  qualitative analysis methods, looking for patterns, themes, and
  insights into participants' experiences, behaviors, or attitudes.
- **Reporting** — interpret and summarize results, using quotes or
  excerpts from the diaries to illustrate key points.

## Why capture experience over time, in context

Many experiences — mood, habitual behavior, a product used repeatedly
over weeks — are hard to reconstruct accurately after the fact, and
awkward or artificial to observe directly in the moment without
disrupting them. A diary study lets participants report close to the
moment of experience, in their own natural context, over a period long
enough to capture change and variation that a single interview or lab
session would miss entirely.

## Common pitfalls

- **Vague or overly broad recording guidelines** — participants left
  unsure what counts as worth recording tend to produce inconsistent,
  hard-to-compare entries; give concrete examples of what to log.
  Guidelines that are too rigid, though, can suppress unexpected but
  valuable observations — the balance matters.
- **Participant fatigue and dropout** — a diary study asks for sustained
  effort over time; too high a recording burden (long entries, too
  frequent) tends to reduce compliance and entry quality as the study
  goes on.
- **No follow-up interview or context-gathering** — raw diary entries
  can be terse or ambiguous; a debrief interview after the diary period
  often surfaces context and clarification the entries alone don't
  capture.
- **Treating diary entries as fully objective data** — entries reflect
  what participants chose to notice and record, filtered through their
  own perspective; that's a feature for understanding subjective
  experience, but a limitation if treated as an objective behavioral
  log.

## Learn more

- [[task-analysis]] for a related but more structured, task-focused research technique.
- [[icebreaker-questions]] for building rapport with participants in qualitative research more generally.