The Inventory of Problems is sensitive and specific to experimentally induced malingering: a study in a Spanish-speaking Cuban sample

This study was designed to evaluate the classification accuracy of the Inventory of Problems with Memory Module (IOP-29-M) in Cuban university students using the experimental malingering (expMAL) paradigm. The IOP-29-M was administered to 76 Cuban students (43 female; MAge = 21.5; MEducation = 13.9) randomly assigned to the control (n = 51; standard instructions) or the expMAL condition (n = 25; instructed to feign neuropsychological impairment). The effect of expMAL was more pronounced on the IOP-29 (d = 1.98) than commonly used symptom inventories (d: 1.28–1.36). The standard IOP-29 cutoff (≥.50) achieved .64 sensitivity at .92 specificity (82.9% overall correctly classification). Similarly, expMAL had a larger effect on the IOP-M (d = 1.38) than a verbal memory test (d: 0.63–1.01). An IOP-M ≤ 32 produced .56 sensitivity at .90 specificity (78.4% overall correct classification). Combining the two indicators (IOP-29-M) correctly classified 85.5–94.3% of the sample. Critical item analysis on the IOP-M produced marginal improvements in classification accuracy. Results provide proof of concept for the utility of the expMAL paradigm in Cuba. The IOP-29-M produced strong classification accuracy, demonstrating its cross-cultural validity. More research is needed using larger and demographically/geographically more diverse samples, including clinical patients.