Is there any way (or best practise) to measure the perceived workload caused by a software on a certain user?

Question

Perceived Workload has a subjective character trait, but I would like to find a way how one can measure for example the perceived workload from any individual. Here I mean the workload, which is caused by a single software on the person, who has to work with it.

The software I am talking about provides work items as some part of a workflow from a project team. And here I would like to find out, what is circa the optimal amount of work items (for example daily) for one single stakeholder in order to avoid fatigue or cognitive overload. (The work items themselves always take circa same efforts and time)

Are there any best practices for my matter or any (scientifically) proven ways to do this?

Answer 1

You could observe how many tasks the user can complete and how long it takes them. A way of conducting this is to create hypotheses based on assumptions. Here's an example:

Assumption: Users can only handle up to 100 Tasks per day before becoming fatigued.

Hypothesis: We believe a User will be able to handle 100 tasks a day, before getting fatigued

You could also find out the drop off rate. How long is a user doing these tasks until they stop or leave.

You need to collect data by observing your test subjects. With that data you'll be able to analyze. Based on your findings you can come up with conclusions.

Answer 2

There are four main methods for measuring (cognitive) workload to the current state of art:

• Self-report scale-based measures: User ranks himself the experienced level of workload on single or multiple rating scales, such as the NASA TLX
• Performance measures: How long did it take to finish given tasks? What is the quality of the results?
• Physiological approach: Studies in this context mainly use galvanic skin response or the heart rate as indicator for workload.
• Behavioral measures: Make use of any interactive patterns. One can find studies about mouse-events, linguistic patterns and so on.

There are also multimodul cognitive load measurement approaches, combining different stated methods. See: Fang Chen et al. 2012 - Robust Multimodal Cognitive Load Measurement