The English-language version of the Self-Report Symptom Inventory: a pilot analogue study with feigned head injury sequelae.

Questionnaire-based symptom validity tests (SVTs) are an indispensable diagnostic tool for evaluating the credibility of patients' claimed symptomatology, both in forensic and in clinical assessment contexts. In 2019, the comprehensive professional manual of a new SVT, the Self-Report Symptom Inventory (SRSI), was published in German. Its English-language version was first tested in the UK. This experimental analogue study investigated 20 adults simulating minor head injury symptoms and 21 honestly responding participants. The effect sizes of differences between the two groups were large, with the simulating group endorsing a higher number of pseudosymptoms, both on the SRSI and the Structured Inventory of Malingered Symptomatology, and scoring lower on the Reliable Digit Span than the control group. The results are similar to those obtained in previous research of different SRSI language versions, supporting the effort to validate the English-language SRSI version.