Psychosis as a confounder of symptom credibility testing in a transcultural sample

To check the credibility of impairments reported by refugees, so-called performance validity tests may be administered. We explored whether a psychotic condition may compromise performance on such test in patients admitted to a referral center for refugee mental health in the Netherlands (n = 231). We selected patients with no clear incentive to exaggerate their complaints (n = 80); psychotic patients in this subsample (n = 44) made significantly more errors on a simple forced-choice emotion recognition task than non-psychotic patients (n = 36), means being 9.0 (SD = 6.8) and 5.9 (SD = 5.1), respectively. Next, we selected patients with an incentive to deny complaints (n = 24); 79% of these patients had a psychotic disorder. Their failure rate on the emotion recognition test (21%) was the same as the failure rate of a control group of Dutch chronic psychotic patients (n = 47), but significantly above that (2%) of a control group of healthy controls (n = 51). We regard this as preliminary evidence that psychotic symptoms and/or antipsychotic medication may put a constraint on testing symptom credibility in refugees.