A Comparative Study of Iranian Smell Identification Test (Iran-SIT) and Single-photon Emission Computed Tomography (SPECT) Results in Discrimination of Anosmia and Malingering in Forensic Cases

Abstract

Purpose: Olfactory dysfunction is a common complaint following head trauma. Few subjective and objective tests had been proposed for purposes of litigation. Currently, the two most common methodologies for separating malingerers from genuine anosmics are single-photon emission computed tomography (SPECT) and smell identification tests as objective and subjective tests, respectively. The objective of the present study was to compare the efficacy of the SPECT and Iranian Smell Identification Test (Iran-SIT) in discrimination of anosmia and malingering in forensic cases. Method: All of the 16 subjects that fulfilled the requirements completely, underwent both SPECT imaging and Iran-SIT assessment. Results: The sensitivity of SPECT in diagnosing malingering and anosmia was estimated to be 66.6% and 87.5%, respectively. That of Iran-SIT was estimated to be 90% and 75%, respectively. In addition, the sensitivity and specificity of Iran-SIT in diagnosing hyposmia were 100%. Conclusion: Because of the higher sensitivity of Iran-SIT in diagnosing anosmia and higher specificity in diagnosing malingering, it is recommended for directly ruling out the suspicious cases.