Next-generation negative symptom assessment for clinical trials: Validation of the Brief Negative Symptom Scale

Abstract

The current study examined the psychometric properties of the Brief Negative Symptom Scale (BNSS), a next-generation rating instrument developed in response to the NIMH sponsored consensus development conference on negative symptoms. Participants included 100 individuals with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder who completed a clinical interview designed to assess negative, positive, disorganized, and general psychiatric symptoms, as well as functional outcome. A battery of anhedonia questionnaires and neuropsychological tests were also administered. Results indicated that the BNSS has excellent internal consistency and temporal stability, as well as good convergent and discriminant validity in its relationships with other symptom rating scales, functional outcome, self-reported anhedonia, and neuropsychological test scores. Given its brevity (13-items, 15-minute interview) and good psychometric characteristics, the BNSS can be considered a promising new instrument for use in clinical trials.

Psychometric evaluation of the negative syndrome of schizophrenia

“…Its convergent validity was good as demonstrated by the correlation coefficients between the BNSS total score and the SANS total, BPRS negative and PANSS negative subscale scores (0.84, 0.68 and 0.80, respectively) [3,35]. With regard to the discriminant validity, as expected, there was no statistically significant correlation with the BPRS positive score (r = −0.06) nor with the PANSS positive subscale score (r = 0.09) or with the cognitive function as measured by the WASI (r = −0.13), while the scale showed moderate correlation with the PANSS general psychopathology score (r = 0.4) [3,35].…”

“…In addition for two negative symptoms-avolition and asociality-the BNSS differentiates between internal experiences and behaviours [35]. Although this distinction may help to clarify and assess the true nature of the negative symptoms, i.e.…”

“…anhedonia/avolition/asociality (accounts for 57-57.9 % of the variance) and emotional expressivity (accounts for 14-10.8 % of the variance) [3,35]. However, a recent paper [37] has shown that the best solution was a threecomponent structure, i.e.…”

Effort-based decision making as an objective paradigm for the assessment of motivational deficits in schizophrenia

“…Further, current "gold standard" methods of evaluating motivational deficits rely on clinical ratings usually based on patient self-report (Strauss et al, 2012;Kring et al, 2013). Recently, several studies have employed performance-based tasks to objectively demonstrate effortrelated motivational deficits in patients with schizophrenia (Fervaha et al, 2013c;Gold et al, 2013;Barch et al, 2014;Wolf et al, 2014;Docx et al, 2015;Hartmann et al, 2015;Treadway et al, 2015).…”

The association of neurocognitive impairment with diminished expression and apathy in schizophrenia

“…The severity of negative symptoms has been reported to correlate with neurocognitive impairment crosssectionally with weak to moderate effect sizes (Addington et al, 1991;Strauss et al, 2012b). However, there is still a debate about the nature of their relationship (Harvey et al, 2006).…”