Validation of a Psycho-Sensory hAllucinations Scale (PSAS) in schizophrenia and Parkinson's disease

abstract Article history:Received 27 June 2014Received in revised form 3 November 2014Accepted 3 November 2014Available online xxxxKeywords:Parkinson's diseaseSchizophreniaHallucinationsScales Objective: Ifhallucinationsare themost common of schizophrenicsymptoms, they have beendescribed inotherpathologies such as Parkinson's disease (PD) but may differ considerably in their phenomenology. However, nomulti-modalclinicalscalewithatransnosographicapproachhasbeendevelopedtoday.Thepurposeofthisstudywastocreateandvalidateanewtoolforthehetero-assessmentofallsensorymodalitiesofhallucinationsschizo-phrenia (SCZ) and in PD.Method:Scaleitemsweregeneratedbyliteraturereviewandvalidatedbymedicalboard.AstudywasthenmadetoevaluatepsychometricpropertiesofthePsycho-SensoryhAllucinationsScale(PSAS)thatincludefourdomains(auditory, visual, olfactory and gustatory, cenesthetic modalities) and one specificitem‘guardian angel’.Results:Itwasthenvalidatedin137patients:86PD(53.5%male;meanage=53.3years)and51SCZ(64.7% male;mean age = 38.5 years). Factorial analysis of the PSAS foun d four factors. The PSAS showed good internal consis-tency [Kuder–Richardson alpha coefficient 0.49 to 0.77] and good test–retest reliability [Agreement % = 0.75 to0.97] and inter-rater reliability [Agreement % = 0.78 to 1.0]. The convergent validity illustrates the concomitantevaluation of the concept between PSAS and PANSS P3 and UPDRS1 I2.Conclusion: The PSAS can be useful to describe the whole halluc ination and its evolution during the course of thedisease and treatment in schizophrenia and PD. Moreover, it can allow us to undertake a clinic-pathologicalcomparison of hallucination modalities between these two diseases, to enhance our understanding of their preciseneurological mechanisms.© 2014 Elsevier B.V. All rights reserved.