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RON DE Graaf

2 papers in the library · publishing 2007-2021

Papers

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Schizophrenia and the Environment: Within-Person Analyses May be Required to Yield Evidence of Unconfounded and Causal Association—The Example of Cannabis and Psychosis

Schizophrenia Bulletin March 8, 2021 Jim van Os, L. Pries, M. Ten Have et al.

Abstract Hypotheses about the link between cannabis use and psychosis apply to the within-person level but have been tested mostly at the between-person level. We used a within-person design, in which a person serves as his own control, thus removing the need to consider confounding by any fixed (genetic and nongenetic) characteristic to study the prospective association between cannabis use...

Does normal developmental expression of psychosis combine with environmental risk to cause persistence of psychosis? A psychosis proneness–persistence model

Psychological Medicine April 1, 2007 Audrey Cougnard, Machteld Marcelis, Inez Myin-Germeys et al.

Background. Research suggests that low-grade psychotic experiences in the general population are a common but transitory developmental phenomenon. Using two independent general population samples, the hypothesis was examined that common, non-clinical developmental expression of psychosis may become abnormally persistent when synergistically combined with developmental exposures that may impact...