Biomedical subjects

Stephanie McDermid Vaz

Publications and source records attributed to Stephanie McDermid Vaz.

3 recordsLinked to original sources

PubMed2006

The University of California Performance Skills Assessment (UPSA) in schizophrenia.

This study evaluated the University of California Performance-based Skills Assessment (UPSA) in a Canadian outpatient schizophrenia setting. The UPSA was administered to 64 patients with schizophrenia and schizoaffective disorder and to 42 nonpsychiatric controls. Patient and control samples did not differ in age, gender composition, first language or country of birth. Patients demonstrated significantly lower performance than healthy participants on 3 of 5 UPSA subscales as well as on a summary index. Moreover, performance varied significantly with patients' support requirements in the community. In contrast, the Household Management and Transportation subscales yielded non-significant group differences and failed to correlate with community support requirements. Examination of score distributions raised the possibility of a ceiling effect that limited the discriminating power of UPSA subscales, thus imposing qualifications on clinical interpretations of this instrument. Performance-based assessment of life skills provides an important new perspective on functional outcome in schizophrenia and serious mental illness. However, psychometric properties, task difficulty and the nature of different mental health settings, populations and communities must be considered in the design and application of these instruments.

Adolescent↗

PubMed2006

Stability and validity of memory-based subtypes of schizophrenia.

This study assessed whether verbal memory performance indexed by the California Verbal Learning Test (CVLT) can organize and reduce the heterogeneity of schizophrenia. The temporal stability, cognitive and clinical validity of: (a) a putatively cortical-subcortical-normative typology derived from dementia patients' scores on the CVLT and (b) a memory performance dichotomy based on a psychometric criterion and 1 CVLT summary score were evaluated. These memory subtypes were examined in 102 schizophrenia patients, 55 of whom were assessed again 3 years later. The results indicate that both methods yield potentially valuable illness distinctions on a cross-sectional basis, but fail to show truly trait-like properties. Furthermore, the evidence favors the validity of a parsimonious dichotomy over a more complex dementia-based typology.

Adult↗

PubMed2004

Verbal memory errors and symptoms in schizophrenia.

OBJECTIVE: To extend and test hypotheses linking positive and negative symptoms to selective aspects of verbal memory in schizophrenia. BACKGROUND: Verbal memory includes the ability to discriminate and prevent the intrusion of irrelevant information into recall and recognition. This ability has been proposed as a cognitive process that differentially mediates positive and negative symptoms. METHOD: Four error discrimination and 1 general recall memory index from the California Verbal Learning Test as well as general ability (IQ) and sex were used as predictors of symptom ratings in 55 schizophrenia patients within a regression framework. RESULTS: Intrusion errors during free recall contributed significantly to the prediction equation for negative symptoms (Brief Psychiatric Rating Scale). In contrast, positive symptoms and general psychopathology were not predicted by any of the discrimination indices. However, general recall memory (California Verbal Learning Test total words trials 1-5) contributed significantly to the prediction of general psychopathology and marginally to the prediction of negative symptoms. CONCLUSIONS: Impaired recall memory predicts levels of nonspecific psychopathology in schizophrenia. Negative symptoms associate with low intrusion error rates, but there is no evidence of an association between elevated errors and positive symptoms.

Adult↗