ISCTM 2012 Scientific Meeting – Negative Symptoms Summary
ISCTM Negative Symptoms Working Group Dinner
21 February 2012
Chairs: S Marder, D Daniel
J. Rabinowitz updated the group on NEWMEDS, an initiative in which pharmaceutical companies are sharing some of their data on negative symptoms in schizophrenia. The database now holds from 5 companies including 23,000 patients with schizophrenia, generally from studies in acute schizophrenia. Estimates of the percentage of patients with schizophrenia with prominent negative symptoms vary widely depending on which of the various definitions in the literature is employed. A discussion ensued on whether one can even talk about some patients having predominantly negative symptoms without making positive and negative ‘competing’ domains .
Dr. Marder also informed the group about an international meeting on negative symptoms methods that will be held in Florence on April 19, 2012. Interested members may contact him for additional information.
S. Marder provided an update on the development of the CAINS scale, a new negative symptoms scale being developed by a working group that grew out of the NIMH-MATRICS Consensus Development Conference on Negative Symptoms. The CAINS had 24 items in beta testing but is now down to 16 items in 2 subscales: the experience subscale and the expression-related subscale. These 2 subscales are intended to be scored separately and not to yield a total score.
The CAINShas been studied in 160 patients at 4sites for test-retest reliability for and convergent and divergent validity and has been found to have good reliability, especially for the experience subscale, and good convergent validity with other negative symptoms scales and with the UPSA and some cognitive measures. The final version of the CAINS will be posted sometime in the early spring.
D. Daniel discussed the BNSS, the Brief Negative Symptom Scale, a 13 item scale that also grew out of the NIMH-MATRICS Consensus Development Conference on Negative Symptoms. It is in development and has shown good reliability and concurrent and discriminant validity. A paper on the psychometric properties of the scale was published in 2011 by Kirkpatrick et al in the Schizophrenia Bulletin.
The group discussed the question of how and when informants should be used in rating negative symptoms. Caregivers have valuable information about patients’ symptoms but they have they own agendas and varying levels of contact with patients possibly leading to increased variability in the results.
Two issues proposed for future discussions were:
1) Does it make sense to exclude patients with depressive symptoms when studying negative symptoms ?
2) Are there any physiologic measures that could be used in studying negative symptoms?