Distinguishing invitation groups in e-mail invitations with questfox

questfox allows to use different invitation groups in the e-mail invitation process.

What are invitation groups?
By using invitation groups one can better control the sample by inviting different people separately into a survey. A simple invitation group may be male vs. female. A complex invitation group may be age categories or differentiations of client descriptions.

While uploading your e-mail addresses make sure, that you have assigned a value to each case containing the invitation group’s value. The group can be a standard alphanumeric value. So you can really call the group “female”, “male” “unknown” etc. Attention: the selection of the group in the process is case sensitive. “Test” is not equal to “test”

During the invitation it is then possible to select people out of a defined group. Just type in the group name and define how many of those group members you would like to select from the list

Under Options it is possible to apply some additional features:

  • Randomization
  • Amount of reminds (default=0)
  • Number of selections from the list

In the following example 500 respondents from the group “1” are randomly selected.


Depending on the size of your sample the selection process may take a while. Please wait for your browser to have finished the selection process.

If you plan to work through your list step by step you can also do several selections at a time before inviting the selected potential respondents. Example: Select 500 from group 1 and then 300 from group 2 etc.

These powerful features will help you to create better samples. With the soon to come functionality of scheduling e-mail invitations this will make your research better with less work needed.


Grid Lines in questfox Living Reports can be switched off

A small improvement before the week-end starts: A simple setting in the charting settings of the questfox living report chart visualisation allows you to just not show any grid lines. It is not much, but it helps.

Here is before…


…changing the setting Show Grid Lines


… and after:


With this simple improvement your creativity of creating living reports is a little less limited to the technical barries. Just test it….


Image and Video pre-load for graphical stimulus control in questfox

With the new features of questfox more and more users are incorporating graphical stimuli into survey with exact time measurement. Some projects use more than 20 MB of graphical material during one survey. Even though we would always recommend to compress the data to the maximum possible still there is the issue of loading time of graphical material.

Our development team is happy to announce the integration of a background pre-loading mechanism for graphical stimuli inside of questfox.

The snippet can be integrated in any HTML question page in your questfox project. Just make sure that you allow enough time for your stimulus material to be loaded before showing it to your respondents.

This is the snippet that you might want to put into a hidden question inside of a questfox question. Please make sure, that you exchange the filenames with the right directory.


In case you want to test a video in the survey it makes sense to pre-load this video into the cache of a participant’s browser before you show it later by using the style=”display: none;”.

<p><video style="display: none;" src="https://YOUTVIDEOFILE.mp4" autoplay="autoplay" muted="" width="300" height="150"> </video></p>

Tachistoscope in questionnaires with questfox

In the old day a tachistoscope was a hardware device allowing to control the exposition of a picture for an exactly controlled amount of time. This was heavily used in psychology and marketing to figure out effects of understanding and processing time of the human brain.

questfox allows a similar function in the world of software. A tachistostoscope feature can be easily implemented into questfox by setting a time frame for the exposition of a stimulus.

After creating any kind of question page you can define an amount of time in which questfox automatically presses next. The questionnaire will move on after this defined time.

If you want to force the respondents to pass a defined minimum amount of time on the page you can additionally define the delay in seconds.

Here is the setting unter Page Settings tachistoscope_in_questfox

Make sure, that your approach is doable for your selected respondents and also think about the needed loading time for pictures before measuring the time.

This feature can also be used to set time pressure to respondents in choice tasks etc.