Often, you'll want a visual reference for the participant to view while responding to questions. For example, an image, video, or table of text. Read on to learn about how to upload a stimulus, file format options, and best practices.

How can I upload a stimulus?

You can add a stimulus to any question in your Study guide setup. Locate the question you'd like to include a stimulus and select the gear wheel. In the Question settings, select stimulus and enable.

What file formats are accepted?

You can upload the following as a stimulus:

1. Image files - either PNG or JPEG

2. Video files - MP4 (under 20M)

3. Audio files (e.g., a song) - Save this as an MP4 with a blank or placeholder image

Please note that the file size is limited to 20MB and be aware that large file sizes (e.g., a long video) could take slightly longer to upload.

A few things to keep in mind...

• We do not have the option to upload Excel files, PDFs, PPTs, or Word Docs - if you have content in those formats, you should adapt and export the content to PNG/JPEG

• Be sure to check the image resolution when testing your guide to confirm the image/ video quality is high

• Visibly label content and options - for example, if you are getting feedback on 6 different products, label those products with titles like "CONCEPT A, CONCEPT B" or "IMAGE 1, IMAGE 2", etc. (see an example below)

Set Timer for Stimulus

Sometimes, you may want to limit a participant's exposure to a stimulus. For example, when capturing a first reaction to an ad concept, you can mimic the live experience by displaying the ad for only a few seconds.

Set a timer for how long participants will be able to view your stimulus. If you leave the field blank, the stimulus will remain on the screen for the duration of that question.

🚨 Note: Timed stimulus display is only available for images, and is not available for video, URL, and any mobile study types.

Example of stimulus testing set-up

For example, let's say you're a pet company considering running an ad to support a donation campaign. You want to get feedback on which dog image is more compelling from two images.

For each image, you could set up a guide section with the following questions.

• What are your initial reactions to this image? What do you like or dislike?

• What do you imagine this dog's life is like? Who do they live with? What do they enjoy doing?

• On a scale of 1 to 5 where 5 is Extremely Cute, how cute would you rate this corgi?

For each of those questions, you can upload the relevant image as a stimulus.

After getting feedback on each individual image, it's also common to want to get feedback on both images -

• For example, you could do a multiple choice question where you ask which image they prefer (A or B).

• Alternatively, if you have many different options, you could try a stack ranking question or a "select up to X" multiple choice

For this sort of comparison, people often put together a slide that labels each image, and then you can export the slide as a PNG or JPEG file for uploading.

Participant perspective

When the participant is taking the interview, they will see the stimulus to the right of the interview question for a desktop/laptop-based question.
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They can click "Expand" to zoom in and view the image more closely.

Similarly, the stimulus image is also available for participants on mobile phone - the participant will first see the interviewer question, and then click "View image" to view the stimulus.

Common FAQ about adding a Stimulus

Are stimulus images or videos protected from download?

Yes. Outset includes several built-in measures to help prevent participants from downloading stimulus content during a study.

These protections include:

• Blocking the right-click context menu on stimulus images

• Preventing images from being dragged out of the interface to download them

• Disabling video downloads for uploaded stimulus videos

These protections help reduce casual downloading of research materials during a session.

However, as with any online platform, it is still possible for participants to capture content using external workarounds (for example, taking a photo of their screen or recording with another device). Because of this, researchers should avoid showing highly sensitive or confidential materials unless appropriate precautions are taken.

What is the limit on file size for stimulus uploads?

1. Image stim uploads: 20MB max, JPEG and PNG only

2. Video stim uploads: 2GB per file max

3. Researcher video uploads (BYOD): 20 GiB total per survey, max 20 files
   
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