Technical comment on Krupić, D., Žuro, B., & Corr, P. J. (2021): Anxiety and threat magnification in subjective and physiological responses of fear of heights induced by virtual reality. Personality and Individual Differences, 169, 109720

In the study of Krupić et al. (2021), the Moodmetric® Ring was used to measure electrodermal activity (EDA), which known to be related to a person's stress level. The Moodmetric® software produces a so-called MM-value, a standardized stress score between 1 and 100. An important requirement for interpreting this MM-value, is the implementation of a 12 hour calibration period. As this study did not implement such a period (i.e. test subjects wore the ring for 45 min), the MM-values should not be interpreted as reported in this study. Although the main conclusion of the study remains valid, it is of great importance to be transparent regarding the processing of physiological measurements, and discuss factors influencing its interpretation. This will contribute to comparability between studies in the field of stress measurements and the valid usage of physiological measurement tools.