Detecting Symptom Overreporting: Equivalence of the Dutch and German Self-Report Symptom Inventory

The Self-Report Symptom Inventory (SRSI) intends to measure symptom overreporting. To assess the Dutch and German SRSI equivalence, both versions were split into two half-forms. Forty bilingual participants were randomly allocated to two groups that completed the first half in German and the second half in Dutch or vice versa. Each group completed the SRSI honestly and then under feigning instructions. For both conditions, the Dutch and German SRSI did not statistically significantly differ within and across the two groups. For most comparisons, the Bayes factor was ≥ 3, indicating moderate evidence favoring the equivalence of language versions and half-forms. Genuine and pseudosymptoms endorsement was significantly higher in the feigning than in the honest condition (both Zs = 5.44, rrb = 1.00). The SRSI standard cut score correctly identified honest responding and detected 80% of feigned responses. Our results align with Giger and Merten’s (2019) German and French SRSI equivalence study.