AUTHOR=Tran Bach Xuan , Nguyen Tham Thi , Boyer Laurent , Fond Guillaume , Auquier Pascal , Nguyen Hao Si Anh , Tran Ha Thi Nhi , Nguyen Hung Manh , Choi Jongkwan , Le Huong Thi , Latkin Carl A. , Nathan Kalpana Isabel , Husain Syeda F. , McIntyre Roger S. , Ho Cyrus S. H. , Zhang Melvyn W. B. , Ho Roger C. M. TITLE=Differentiating people with schizophrenia from healthy controls in a developing Country: An evaluation of portable functional near infrared spectroscopy (fNIRS) as an adjunct diagnostic tool JOURNAL=Frontiers in Psychiatry VOLUME=Volume 14 - 2023 YEAR=2023 URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2023.1061284 DOI=10.3389/fpsyt.2023.1061284 ISSN=1664-0640 ABSTRACT=This study aimed to evaluate portable functional near‑infrared spectroscopy (fNIRS) device as an adjunct diagnostic tool in Vietnam to assess hemodynamics when people with schizophrenia and healthy controls performed cognitive tasks. Eighty-two participants were divided into schizophrenia and healthy controls group (110:55), which were recruited by match of age, gender, and family psychiatric history of psychiatric illnesses. Hemodynamic responses in the frontal cortex were monitored with a 48-channel portable device during the Stroop Color-Word Test (SCWT) and Verbal Fluency Test (VFT). General linear model compared the differences in oxyhemoglobin (HbO2) levels between the two groups. The Receiver Operating Characteristic (ROC) graph was generated for each neuroanatomical area. People with schizophrenia did not show significant activation in the frontal lobe during the SCWT and VFT as compared to pre-task. During the VFT, the area under the ROC curve of the bilateral dorsolateral prefrontal cortex, bilateral orbitofrontal cortex, right frontopolar prefrontal cortex, and left ventrolateral prefrontal cortex were greater than 0.7 (p <0.001). The area under the ROC curve (AUC) for the right orbitofrontal cortex was maximal during the VFT [AUC = 0.752, 95%CI = 0.674 – 0.831]. The Youden’s index reached a peak (0.48) at the optimal cut-point value (HbO2 cutoff < 0.209 µmol/ml for schizophrenia) in which the sensitivity was 76%; specificity was 72%; positive predictive value was 0.73; negative predictive value was 0.75 and correct classification rate was 73%. Assessing hemodynamics during VFT by portable fNIRS offers the potential as an adjunct diagnostic tool for schizophrenia in developing countries.