You might ask Lucas Steuber, he created such a corpus for his master's degree (or PhD, I don't remember).

https://www.linkedin.com/in/lsteuber/

You might be interested in the articles that discuss not Schizophrenia, but other illness, autism:

[1] Abdelrahman, M., Ali, A., Farag, A., Casanova, M. F., and Farag, A. 2012. New Approach for Classification of Autistic vs. Typically Developing Brain Using White Matter Volumes. In 2012 Ninth Conference on Computer and Robot Vision. IEEE, 284–289. DOI=10.1109/CRV.2012.44.

[2] Adams, A. and Robinson, P. 2011. An Android Head for Social-Emotional Intervention for Children with Autism Spectrum Conditions. In Affective Computing and Intelligent Interaction, S. D’Mello, A. Graesser, B. Schuller and J.-C. Martin, Eds. Lecture Notes in Computer Science. Springer, Berlin, Heidelberg, 183–190. DOI=10.1007/978-3-642-24571-8_19.

[3] Alcorn, A., Pain, H., Rajendran, G., Smith, T., Lemon, O., Porayska-Pomsta, K., Foster, M. E., Avramides, K., Frauenberger, C., and Bernardini, S. Social Communication between Virtual Characters and Children with Autism. In LNAI, 7–14. DOI=10.1007/978-3-642-21869-9_4.

[4] Chung, W. and Shin, C. S., Eds. 2017. Advances in Affective and Pleasurable Design. Proceedings of the AHFE 2016 International Conference on Affective and Pleasurable Design, July 27-31, 2016, Walt Disney World®, Florida, USA. Advances in Intelligent Systems and Computing 483. Springer, Cham, s.l.

[5] Conti, D., Di Nuovo, A., Trubia, G., and Buono, S. Adapting Robot-Assisted Therapy of Children with Autism and Different Levels of Intellectual Disability: A Preliminary Study. In HRI’18 Companion. DOI=10.1145/3173386.3176962.

[6] Duquette, A., Michaud, F., and Mercier, H. 2008. Exploring the use of a mobile robot as an imitation agent with children with low-functioning autism. Auton Robot 24, 2, 147–157.

[7] Hideki Kozima, Yuriko Yasuda, and Cocoro Nakagawa. 2007. Social interaction facilitated by a minimally-designed robot -- Findings from longitudinal therapeutic practices for autistic children.

[8] Nikolopoulos, C., Kuester, D., Sheehan, M., and Dhanya, S. Investigation on Requirements of Robotic Platforms to Teach Social Skills to Individuals with Autism 59, 65–73. DOI=10.1007/978-3-642-19385-9_9.

[9] Tsai, T.-W. and Lin, M.-Y. 2011. An Application of Interactive Game for Facial Expression of the Autisms. In Edutainment technologies. Educational games and virtual reality/augmented reality applications ; 6th International Conference on E-Learning and Games, Edutainment 2011, Taipei, Taiwan, September 7 - 9, 2011 ; proceedings, M. Chang, W.-Y. Hwang, M.-P. Chen and W. Müller, Eds. Lecture Notes in Computer Science 6872. Springer, Berlin, 204–211. DOI=10.1007/978-3-642-23456-9_37.

HPH, Alexander

You can use the Aggregate Content of ClinicalTrials.gov (AACT) https://aact.ctti-clinicaltrials.org. You can also go to https://corpus.byu.edu/iweb/ and compose your own corpus.

Have you find some dataset? I'm interested in the same

Samane Shahmohamadi

You might find these language excerpts from a long time ago useful.

Ajit kumar Roy

you can find:

BIBLIOGRAPHY OF FIRST-PERSON NARRATIVES OF MADNESS I ENGLISH (5th edition)

on: www.gailhornstein.com

you can get it in https://www.mit.edu.et

I need it, too.