Image of a participant and checkmarks representing experimental control for psychology experiments

Experimental Control

The rise of remote research makes a lot of psychologists wonder about the soundness and extent of experimental control that having a study online has to offer. In a lab setting, researchers try to control as many potential confounds as possible to avoid accidentally introducing additional variability that could impact the observed results.

Background

To ensure experimental control, a specific protocol is put in place before an experiment begins. The protocol is designed in order to minimize unwanted effects as much as possible. This might include defining how far a participant is seated away from a screen, demographic requirements, or device specifications.

Researchers conducting in-person experiments have control over many factors as they are able to take matters in their own hands and this is one of the main reasons why experiments are often performed in laboratories. However, remote studies require a strong system in place in order to assure experimental control because the researcher is not immediately present to directly oversee the participant.

Our process: The pipeline bringing experimental control online

To ensure experimental control for online studies, we employ a number of advanced techniques and methods to ensure that high-quality data is captured from participants completing the experiment remotely. These methods are classified into three broad categories:

  1. Controlling the device and hardware: Taking into account factors relating to the hardware, such as device specifications or screen size.
  2. Controlling the participant and environment: Controlling the who, the characteristics of the participants you want completing your study, as well as their remote environment, such as lighting.
  3. Controlling engagement: Monitoring engagement such as attention during the experiment, bot checks, and more.

Experimental control is accomplished by measuring and accounting for these three broad categories.

Device & Hardware: Experimental Control

In a lab setting, you already know your computer or tablet specifications, what devices you are using, and their CPU and GPU speed. However, when performing your study online, these will vary across the participants.

With Labvanced you can specify and restrict: what kind of devices and browsers you want to allow in your study, the desired monitor refresh rate, as well as minimum and maximum screen size, as well as screen orientation in the case of studies conducted on mobile devices.

Furthermore, any issues with delays and CPU speed are reported due to the strict methods we have in place in order to ensure precision timing.open in new window

Lapton open with an internet browser where experimental control is accomplished by reporting browser, device, screen size and more

Participant & Environment: Experimental Control

Additional variables that can influence results pertain to the participant’s characteristics and demographics, as well as their immediate environment.

For a study to be as planned, the participant’s personal demographics are very important, such as their: age, gender, language proficiency, education, job, health status and more. In Labvanced, these parameters can be selected so that the participant is required to provide these upfront before being admitted to proceed further with the experiment. Labvanced also goes a step further by controlling for the participants’ environment. To measure distance from the screen, we calculate the angle from the participant’s blindspot in the eye.

Participant taking part in an psychology study where experimental control is accomplished with attention checks

Engagement: Experimental Control

To ensure appropriate engagement, there are several strategies that can be put in place.

When an experiment begins, it is presented in full-size, ensuring that it is the only thing that the participant sees. If they remove the experiment from fullscreen, the experiment is automatically paused.

In the case of eye tracking,open in new window Labvanced employs a virtual chin rest, so any time that a participant moves too much out of the frame, the experiment stops and the participant is instructed to return to their initial position.

Importantly, bot checks can be addedopen in new window to any study to ensure human participation during an experiment.

Book a demo today to discuss experimental control for psychology online studies.open in new window