Psychometric properties of the German 21-item version of the highly sensitive child scale

Children vary in environmental sensitivity, reflecting heightened responsiveness to positive and negative environments. It is commonly measured through the temperament trait of Sensory Processing Sensitivity (SPS). Currently, no instruments exist in the German language to assess SPS in children. The present study translated the 21-item Highly Sensitive Child Scale (HSC-21) into German and evaluated its psychometric properties using caregiver reports (n = 367) and child self-reports (n = 112). Confirmatory factor analyses supported a bifactor model with a general sensitivity factor and three specific subdimensions (i.e., Ease of Excitation, Low Sensory Threshold, Aesthetic Sensitivity). The German HSC-21 demonstrated full configural, metric and scalar measurement invariance across sex and age groups and good to excellent reliability (internal consistency, test-retest reliability, interrater agreement). HSC-21 scores moderately predicted internalizing problems but not externalizing problems. Consistent with environmental sensitivity theory, Ease of Excitation and Low Sensory Threshold were linked to internalizing problems, whereas Aesthetic Sensitivity predicted better school performance, fewer peer problems, and greater prosocial behavior. The HSC-21 demonstrated meaningful correlations with temperament and personality traits, including positive associations with neuroticism, behavioral inhibition, and sensory sensitivity, and negative associations with extraversion and activity level. Thus, the German HSC-21 represents a reliable and valid measure of SPS and environmental sensitivity.