Sensory processing sensitivity (SPS) is a common human neurobiological trait that is related to many areas of human life. This trait has recently received increased public interest. However, solid scientific research on SPS is lagging behind. Progress in this area is also hindered by a lack of comprehensive research tools suitable for a rapid assessment of SPS. Thus, the aim of this study was to offer a newly developed tool, the Sensory Processing Sensitivity Questionnaire (SPSQ), and to assess its psychometric properties and associations with emotional and relational variables measured during the first wave of the COVID-19 pandemic. We found the tool to have good psychometric characteristics: high temporal stability (r = 0.95) and excellent internal consistency (Cronbach's α = 0.92; McDonald's ω = 0.92). The fit of the SPSQ bi-factor model was satisfactory: χ2 (88.0) = 506.141; p < 0.001; CFI = 0.993; TLI = 0.990; RMSEA = 0.070; SRMR = 0.039. Testing of configural, metric, scalar and strict invariance suggested that the SPSQ assesses SPS equivalently between males and females. The scale's validity was supported via a strong association with an existing SPS measure. Further, we observed higher total SPSQ scores among women, students and religious respondents, and we found that more sensitive respondents reported higher feelings of anxiety and more deterioration in relationships during the COVID-19 pandemic. Thus, this study also identifies people with this trait as being potentially more vulnerable during periods of an increased presence of global stressors.
Keywords: COVID-19; high sensitivity; measurement; psychometric evaluation; sensory processing sensitivity.