Pilot Validation Study of the Japanese Translation of the Brief Negative Symptoms Scale (BNSS)

Valuable interaction with cognitive remediation and optimal antipsychotics for recovery in schizophrenia (VICTORY-S): study protocol for an interventional, open-label, randomized comparison of combined treatment with cognitive remediation and lurasidone or paliperidone

Background

Cognitive impairment, a core feature of schizophrenia, is associated with poor outcomes. Pharmacotherapy and psychosocial treatment, when used alone, have inadequate effect sizes for cognitive impairment, leading to recent interest in combination interventions. A previous study examined the additive effect of cognitive remediation on lurasidone in patients with schizophrenia, which was negative. Although improvement in cognitive function was suggested for lurasidone, it was inconclusive because there was no antipsychotic control in the study. To clarify whether lurasidone has a meaningful impact on cognitive function in combination with cognitive remediation, we use paliperidone as a control antipsychotic in this study. We hypothesize that combination with lurasidone will improve cognitive and social function to a greater extent than paliperidone.

Methods

The valuable interaction with cognitive remediation and optimal antipsychotics for recovery in schizophrenia study is a multicenter, interventional, open-label, rater-blind, randomized comparison study, comparing the effect of lurasidone plus cognitive remediation with that of paliperidone plus cognitive remediation in patients with schizophrenia. The Neuropsychological Educational Approach to Remediation (NEAR) is used for cognitive remediation. Eligible patients will be randomized 1:1 to receive lurasidone or paliperidone combined with NEAR (6 weeks antipsychotic alone followed by 24 weeks combination antipsychotic plus NEAR). The primary endpoint is the change from baseline in the tablet-based Brief Assessment of Cognition in Schizophrenia composite T-score at the end of the NEAR combination treatment period. Secondary endpoints will include change from baseline in social function, schizophrenia symptoms, and quality of life at the end of the NEAR combination treatment period. Furthermore, change from baseline to the end of the pharmacotherapy period and change from the end of the pharmacotherapy period to the end of the NEAR combination treatment period will be assessed for all endpoints. Safety will also be evaluated.

Discussion

Achievement of adequate cognitive function is central to supporting social function, which is a key treatment goal for patients with schizophrenia. We think this study will fill in the gaps of the previous study and provide useful information regarding treatment decisions for patients with schizophrenia.

Clinical trial registration

Japan Registry of Clinical Trials ID, jRCTs031200338.

The Brief negative Symptom Scale (BNSS): a systematic review of measurement properties

BACKGROUND

Negative symptoms of schizophrenia are linked with poor functioning and quality of life. Therefore, appropriate measurement tools to assess negative symptoms are needed. The NIMH-MATRICS Consensus defined five domains for negative symptoms, which The Brief Negative Symptom Scale (BNSS) covers.

METHODS

We used the COSMIN guidelines for systematic reviews to evaluate the quality of psychometric data of the BNSS scale as a Clinician-Rated Outcome Measure (ClinROM).

RESULTS

The search strategy resulted in the inclusion of 17 articles. When using the risk of bias checklist, there was a generally good quality in reporting of structural validity and hypothesis testing. Internal consistency, reliability and cross-cultural validity were of poorer quality. ClinROM development and content validity showed inadequate results. According to the updated criteria of good measurement properties, structural validity, internal consistency and interrater reliability showed good results, while hypothesis testing showed poorer results. Cross-cultural validity and test-retest reliability were indeterminate. The updated GRADE approach resulted in a moderate grade.

CONCLUSIONS

We can potentially recommend the use of the BNSS as a concise tool to rate negative symptoms. Due to weaknesses in certain domains further validations are warranted.

The European Portuguese Version of the Brief Negative Symptom Scale

Negative symptoms reflect a currently much-untreated loss of normal functioning and are frequently found in psychotic disorders. We present the first translation of the Brief Negative Symptom Scale (BNSS) to European Portuguese and evaluate its validity in a sample of Portuguese male patients with a psychotic spectrum disorder. The Portuguese BNSS showed excellent internal consistency, high convergent validity (i.e., strong correlation with the PANSS negative factor), and high discriminant validity (i.e., a lack of association with the PANSS positive factor). In sum, the present European Portuguese BNSS has shown to be reliable, thus extending this instrument's clinical availability worldwide.

Determinants of Recreational Outcomes in Schizophrenia: An Exploratory Study Focusing on Gender Differences

While recreation is impactful for recovery in schizophrenia, no study has examined the effects of schizophrenic symptoms on recreational outcomes. This study examined the determinants of recreational outcomes based on gender. We investigated the relationship between recreational outcomes, positive and negative symptoms, cognitive function, and factors such as negative self-evaluation and evaluation by others. Motivation had a significant impact on both men and women. However, participation in recreational activities was impacted by negative self-assessment for men and evaluations from others for women. The importance of matching strategies based on gender when using recreation therapeutically was emphasized.

Identifying subgroups based on self-assessment of ability in patients with schizophrenia and its relationship with vocational outcomes

Background/Objectives

People with schizophrenia have defective self-assessment of ability (i.e., loss of introspective accuracy [IA]). Although previous studies grouped people according to the degree of IA, the clinical features of these subgroups have not been clarified. Additionally, the determinants of outcomes depending on self-assessment remain unknown. We aimed to identify the clinical features that can help distinguish these subgroups and whether the determinants of vocational outcomes differed between the groups.

Methods

The self-assessment ability of 100 people with schizophrenia was examined and categorized as accurate, over-, or under-estimators. Multiple discriminant analysis was also performed. After demonstrating statistical validity, the relative effects of positive and negative symptoms, cognitive function, and level of IA on vocational outcomes were also examined for each subgroup.

Results

The symptoms that particularly explained the differences between these subgroups were positive and negative (expressing factors) symptoms: p < .001. Using the determinants of vocational outcomes in each subgroup, the over-estimator subgroup was characterized by positive symptoms: p = .025, the under-estimator group, by the underestimation of their own ability: p = .042, and the accurate estimator group, by cognitive function: p = .006.

Conclusion

Reduced IA can be a core mediator of various symptoms. Thus, tailoring the target and strategy of interventions for vocational outcomes according to the accuracy and quality of IA is important in clinical settings.

Defining negative symptoms remission in schizophrenia using the Brief Negative Symptom Scale

INTRODUCTION

This study aimed to propose criteria for negative symptoms remission (NSR) in schizophrenia using the Brief Negative Symptom Scale (BNSS).

MATERIAL AND METHODS

274 participants were assessed on the Positive and Negative Syndrome Scale (PANSS), BNSS and Social and Occupational Functioning Assessment Scale (SOFAS). Two criteria for NSR on the BNSS were proposed - NSR based on the BNSS domains scores (NSR_{BNSS_DOMAINS}) and NSR based on 5 key items of the BNSS (NSR_{BNSS_5ITEMS})_. A SOFAS score of 61 and above was considered as functional remission (FR). Logistic regressions were run to examine the association between FR and NSR. Receiver operating characteristic (ROC) curve analysis was performed for the NSR criteria on FR. Kappa agreement statistic was used to evaluate the agreement between the two NSR criteria.

RESULTS

Eighty-nine (32.5%) participants fulfilled NSR_{BNSS_DOMAINS} criterion whereas 70 (25.6%) participants fulfilled NSR_{BNSS_5ITEMS} criterion. The two NSR criteria had substantial agreement (Kappa statistic=0.797) with each other. Sixty-one (25.3%) participants were in FR. FR was significantly associated with NSR, irrespective of the criterion used. To predict FR, the Area Under the Curve for NSR_{BNSS_DOMAINS} and NSR_{BNSS_5ITEMS} were 0.761 (CI: 0.696-0.826, p<0.001) and 0.723 (CI: 0.656-0.790, p<0.001), respectively. Hence, both NSR criteria demonstrated a fair ability to discriminate between functional remitters and non-remitters.

CONCLUSIONS

Depending on the setting and needs, clinicians and researchers might employ either the full BNSS or an abbreviated 5-item BNSS scale to identify NSR in schizophrenia. More research is needed to further examine the validity of these criteria in schizophrenia.

Study Protocol: The Evaluation Study for Social Cognition Measures in Japan (ESCoM)

In schizophrenia, social cognitive impairment is considered one of the greatest obstacles to social participation. Although numerous measures have been developed to assess social cognition, only a limited number of them have become available in Japan. We are therefore planning this evaluation study for social cognition measures in Japan (ESCoM) to confirm their psychometric characteristics and to promote research focused on social cognition. Participants in the cross-sectional observational study will be 140 patients with schizophrenia recruited from three Japanese facilities and 70 healthy individuals. In our primary analysis, we will calculate several psychometric indicators with a focus on whether they can independently predict social functioning. In secondary analyses, we will assess the reliability and validity of the Japanese translations of each measure and conduct an exploratory investigation of patient background, psychiatric symptoms, defeatist performance belief, and gut microbiota as determinants of social cognition. The protocol for this study is registered in UMIN-CTR, unique ID UMIN000043777.

Defining negative symptoms remission in schizophrenia using the Brief Negative Symptom Scale

INTRODUCTION

This study aimed to propose criteria for negative symptoms remission (NSR) in schizophrenia using the Brief Negative Symptom Scale (BNSS).

MATERIAL AND METHODS

274 participants were assessed on the Positive and Negative Syndrome Scale (PANSS), BNSS and Social and Occupational Functioning Assessment Scale (SOFAS). Two criteria for NSR on the BNSS were proposed - NSR based on the BNSS domains scores (NSRBNSS_DOMAINS) and NSR based on 5 key items of the BNSS (NSRBNSS_5ITEMS). A SOFAS score of 61 and above was considered as functional remission (FR). Logistic regressions were run to examine the association between FR and NSR. Receiver operating characteristic (ROC) curve analysis was performed for the NSR criteria on FR. Kappa agreement statistic was used to evaluate the agreement between the two NSR criteria.

RESULTS

Eighty-nine (32.5%) participants fulfilled NSRBNSS_DOMAINS criterion whereas 70 (25.6%) participants fulfilled NSRBNSS_5ITEMS criterion. The two NSR criteria had substantial agreement (Kappa statistic=0.797) with each other. Sixty-one (25.3%) participants were in FR. FR was significantly associated with NSR, irrespective of the criterion used. To predict FR, the Area Under the Curve for NSRBNSS_DOMAINS and NSRBNSS_5ITEMS were 0.761 (CI: 0.696-0.826, p<0.001) and 0.723 (CI: 0.656-0.790, p<0.001), respectively. Hence, both NSR criteria demonstrated a fair ability to discriminate between functional remitters and non-remitters.

CONCLUSIONS

Depending on the setting and needs, clinicians and researchers might employ either the full BNSS or an abbreviated 5-item BNSS scale to identify NSR in schizophrenia. More research is needed to further examine the validity of these criteria in schizophrenia.

Single versus dual pathways to functional outcomes in schizophrenia: Role of negative symptoms and cognitive function

Background

The functional outcomes for many patients with schizophrenia remain poor, and the specific determinants for and pathways to functional outcomes are not well understood to date. It is unknown whether major determinants of outcomes are achieved via a motivated single pathway or by the motivation and capacity defined in dual pathways. This study investigated whether different aspects of functional outcomes, such as residential, social, and vocational outcomes, are the main determinants of the experience factors for negative symptoms or whether the experience factors and cognitive function are the determinants.

Method

We enrolled 107 patients with schizophrenia. The Social Functioning Scale domains were used to examine whether a single or dual pathway is appropriate for each domain based on the model fit using structural equation modeling.

Results

The model goodness of fit criterion showed a dual pathway for residential and vocational outcomes. In contrast, social and recreational outcomes showed a single pathway.

Conclusion

The major determinants were clearly different for each outcome. Therefore, we emphasize the importance of using different treatment strategies for each outcome. Irrespective of the factors approached, social and recreational outcomes should ultimately focus on motivation. The findings also suggest that interventions should be combined for vulnerable cognitive functions and motivational interventions for residential and vocational outcomes.

Impact of Negative Symptom Domains and Other Clinical Characteristics on Functional Outcomes in Patients with Schizophrenia

Negative symptoms of schizophrenia have generally been defined using five factors; however, few studies have examined the relationship between these five factors and functional outcomes. In addition, there is no definitive conclusion regarding the association between negative symptoms and various aspects of functional outcomes (daily living, social, and vocational). This study is aimed at examining the relationship between these five domains of negative symptoms and different functional outcomes. Patients diagnosed with chronic schizophrenia (n = 100) were selected for the evaluation. We used the Brief Negative Symptom Scale to assess negative symptoms, the Brief Psychiatric Rating Scale to assess positive symptoms, the Schizophrenia Cognition Rating Scale to assess cognition, and the Evaluative Beliefs Scale (negative self-assessment) to assess psychological factors. We analyzed their relative impact on Social Functioning Scale domains using hierarchical multiple regression analysis. Concerning the relationship between daily living and negative symptoms, cognitive function showed the highest association with residential outcomes, such as self-care and shopping, while avolition appeared to show an additional contribution; however, for recreational outcomes, avolition showed the main association, whereas cognitive function showed no additional contribution. For social outcomes, asociality and negative self-assessment showed the main associations, while vocational outcomes were determined by both cognitive function and multiple negative symptoms, such as avolition, anhedonia, asociality, and alogia. Since negative symptom domains appear to differentially impact each outcome, specifically daily living outcome, it is important to evaluate the residential outcomes and recreational outcomes separately. Overall, the present study points to the importance of formulating psychosocial treatment strategies specific for each type of preferred outcome in patients with schizophrenia.

Validation of the Dutch Version of the Brief Negative Symptom Scale

PURPOSE

The Brief Negative Symptom Scale (BNSS) was developed to measure negative symptoms of schizophrenia. However, the Dutch translation of this instrument, called the "Korte Schaal voor Negatieve Symptomen" (KSNS), has not yet been validated. This study investigates the validity and reliability of this Dutch version of the instrument.

PATIENTS AND METHODS

The Psychotic Symptom Rating Scale (PSYRATS), Calgary Depression Scale for Schizophrenia (CDSS), the Health of the Nation Scale (HoNOS) and the KSNS were used for routine outcome monitoring to measure symptoms in 28 patients with a psychotic disorder who were being treated on a long-stay ward.

RESULTS

The internal consistency of the KSNS is fair to good. The inter-rater reliability is excellent. The concurrent validity is moderate but acceptable. The correlations between the KSNS and scales for depression and positive symptoms were not significant, which indicate good divergent validity.

CONCLUSION

Despite the small sample size of the current study, we conclude that the BNSS, called the KSNS in Dutch, appears to be a reliable and valid tool for investigating negative symptoms in detail in patients with psychotic disorders.