Stimulus preparation checklist

Overview

A stimulus is anything you show a participant as part of your study, an image, a video, a prototype, or a piece of creative. How well you prepare it before uploading affects both the participant's experience and the quality of the data you get back. Use this checklist before you upload a stimulus to any study.

Check your file meets the requirements

Different blocks have different limits. For Media and Social Media In-Context blocks, confirm your file is within the maximum file size (20MB) and, for video, the maximum duration (60 seconds), and that it's in a supported format (MP4, M4V, JPG, JPEG, PNG). A file that's rejected or fails to upload during your study setup wastes time you could have caught earlier.

Make sure it's the final version

Double-check you're uploading the actual version you intend to test, not a draft, an old export, or a placeholder. This sounds obvious, but it's one of the easiest mistakes to make when juggling multiple versions of a creative.

Preview it as a participant would see it

Once uploaded, look at how your stimulus actually displays, in a Social Media In-Context block, check it in the platform-specific format (Feed vs. Reel, for example) rather than assuming it looks the same everywhere. For a prototype, confirm every screen is connected and every task flow is clickable before importing, see Before You Begin in the Prototype Test setup article for the full checklist.

Decide if you need multiple versions

If you're comparing creative directions, prepare all versions in advance and upload them together, rather than testing one now and adding another later. This keeps conditions consistent across the versions you're comparing, which matters if you're using Group & Randomization for a monadic or sequential design.

Set up tracking before you publish, not after

If you want Facial Coding or Eye Tracking data on this stimulus, enable it under Technologies before publishing. These settings can't retroactively apply to responses you've already collected.

Add context, not just the file itself

A stimulus alone often isn't enough. Consider whether participants need a short instruction or description alongside it, so they understand what they're looking at and what you're asking them to do with it, rather than being shown an image or video with no framing at all.