Measurement equivalence of PROMIS depression in Spain and the United States.

In this study, we assessed the psychometric properties of the Spanish Patient-Reported Outcomes Measurement Information System (PROMIS) Depression in an adult population-representative sample from Spain (n = 1,503). We tested unidimensionality and local independence item response theory (IRT) assumptions with confirmatory factor and bifactor models under the exploratory structural equations modeling framework. We evaluated item monotonicity assumption with Mokken scaling analysis.

Predictors of Relapse and Functioning in First-Episode Psychosis: A Two-Year Follow-Up Study.

Objective: First-episode psychosis has an annual incidence rate of 24.6 to 40.9 per 100,000 population, and most individuals develop chronic disorders, such as schizophrenia or affective psychosis.

Relationship between cannabis and psychosis: Reasons for use and associated clinical variables.

The mechanism underneath the relationship between cannabis and psychosis remains controversial, for which several hypotheses have been proposed, including cannabis as self-medication and cannabis as a risk for the development of psychosis. The aim of this work was to study the relationship between cannabis and psychosis in first-episode psychosis cannabis users and non-users, and non-psychotic cannabis users. The age at the first psychotic episode, duration of untreated psychosis, psychopathology and reasons for cannabis use were assessed.