When applying physiological measurements as a data collection method, some things need to be planned early on.
Which measurements to apply and what other methods are used (e.g. interviews)
We recommend the Moodmetric smart ring with electrodermal activity measurement to all long term studies that map arousal/stress levels even of large groups of people. Depending on the scope of the study, it is possible to simultaneously collect for example heart rate variability data with other devices and measures. Cortisol levels can be tracked as spot measurements. In short term studies there is a much wider range of physiological signals that can be observed: ECG (electrocardiography), EEG (electroencephalography), facial recognition (video to track emotions) and fEMG (facial electromyography) to mention a few.
Questionnaires, interviews and simple mood questions (happy, neutral, unhappy) are subjective data collection methods. They can be used side by side with physiological data collection methods.
Whichever methods are applied, they should be considered carefully to best match the objectives of the study. It is advisable to ponder following aspects of each method
- How relevant is each method to the study
- Is it subjective or objective
- Is it real-time or is the data visible only after the measurements are completed
- Is data continuous or spot measurement and what is the sample rate / data collection frequency
- What is the accuracy of the chosen method
- What is the cost of the chosen method
Applying several methods at the time requires deep understanding of each of them and how the different data sets complement each other.
How to plan physical device ordering, logistics and use
Physical devices are not questionnaires or software that can be easily distributed among research study participants. They might have long lead times (check each supplier well beforehand), they might need charging and possibly special storage conditions.
When using equipment in a field study, instructing the participants about the correct use is very important. Manuals and guides provide a lot of information on each device, but in addition there might be special tips needed when measuring e.g. a group of 100 persons at the time.
Make plans well ahead of time to be certain that on the first measurement day everything is ready. Always test your research set up with a prestudy.