| Format | Best used when | Watch for |
|---|---|---|
| Scheduled or interval-based | Participants report at a regular cadence when consistent comparison points matter. | The interval may miss the important moment or encourage routine answers. |
| Event-based | Participants report when a meaningful, irregular and recognisable event occurs. | Participants may forget or interpret the trigger differently. |
| Signal-based | The researcher prompts participants when experiences vary across the day. | A signal can interrupt the experience or capture an uninformative moment. |
| Hybrid | The study needs both comparable checkpoints and in-context moments. | The combined workload can become too demanding. |
What Is a Diary Study? A Practical Guide for Researchers
Learn what a diary study is, when it is useful, how to design one, and how to turn longitudinal participant entries into trustworthy research findings.
Jun 6, 2026
SJ
Samuel Jesse
Product Director
What is a diary study?
What can a diary study help you understand?
The main diary study formats
When should you use a diary study?
How to plan and run a diary study
1. Define the decision and research questions
2. Define the participant profiles and sample logic
3. Choose the duration and capture pattern
4. Design and pilot the entries
5. Onboard participants properly
6. Manage fieldwork, not just reminders
7. Close the study and analyse the evidence
How to design diary entries participants can complete
| Research need | Example entry | Why this format fits |
|---|---|---|
| Capture an irregular failure | The next time payment fails, record what you were trying to do and what happened next. | An event-based written or voice entry captures the sequence close to the event. |
| Compare confidence over time | At the end of each workday, rate your confidence using the tool and briefly explain your rating. | A repeated rating supports comparison; the explanation preserves context. |
| Understand a physical setup | After setup, photograph the completed arrangement and describe anything you changed from the instructions. | The image documents the outcome while the explanation captures adaptation. |
| Prepare for a follow-up interview | Save one moment this week when the service did not fit your normal routine. | A lightweight entry becomes a concrete prompt for later probing. |