Structure of Negative Symptoms in Schizophrenia: An Unresolved Issue.
ABSTRACT: Background: Negative symptoms are core features of schizophrenia and very challenging to be treated. Identification of their structure is crucial to provide a better treatment. Increasing evidence supports the superiority of a five-factor model (alogia, blunted affect, anhedonia, avolition, and asociality as defined by the NMIH-MATRICS Consensus); however, previous data primarily used the Brief Negative Symptoms Scale (BNSS). This study, including a calibration and a cross-validation sample (n = 268 and 257, respectively) of participants with schizophrenia, used the Clinical Assessment Interview for Negative Symptoms (CAINS) to explore the latent structure of negative symptoms and to test theoretical and data-driven (from this study) models of negative symptoms. Methods: Exploratory factor analysis (EFA) was carried out to investigate the structure of negative symptoms based on the CAINS. Confirmatory factor analysis (CFA) tested in a cross-validation sample four competing theoretical (one-factor, two-factor, five-factor, and hierarchical factor) models and two EFA-derived models. Result: None of the theoretical models was confirmed with the CFA. A CAINS-rated model from EFA consisting of five factors (expression, motivation for recreational activities, social activities, vocational, and close/intimate relationships) was an excellent fit to the data (comparative fix index = 0.97, Tucker-Lewis index = 0.96, and root mean square error of approximation = 0.07). Conclusions: This study cannot support recent data on the superiority of the five-factor model defined by the NMIH-MATRICS consensus and suggests that an alternative model might be a better fit. More research to confirm the structure of negative symptoms in schizophrenia, and careful methodological consideration, should be warranted before a definitive model can put forward and shape diagnosis and treatment of schizophrenia.
Project description:<h4>Importance</h4>Negative symptoms are associated with a range of poor clinical outcomes, and currently available treatments generally do not produce a clinically meaningful response. Limited treatment progress may be owing in part to poor clarity regarding latent structure. Prior studies have inferred latent structure using exploratory factor analysis, which has led to the conclusion that there are 2 dimensions reflecting motivation and pleasure (MAP) and diminished expressivity (EXP) factors. However, whether these conclusions are statistically justified remains unclear because exploratory factor analysis does not test latent structure. Confirmatory factor analysis (CFA) is needed to test competing models regarding the latent structure of a construct.<h4>Objective</h4>To evaluate the fit of 4 models of the latent structure of negative symptoms in schizophrenia using CFA.<h4>Design, setting, and participants</h4>Three cross-sectional studies were conducted on outpatients with schizophrenia who were rated on the 3 most conceptually contemporary measures: Scale for the Assessment of Negative Symptoms (SANS), Brief Negative Symptom Scale (BNSS), and Clinical Assessment Interview for Negative Symptoms (CAINS). Confirmatory factor analysis evaluated the following 4 models: (1) a 1-factor model; (2) a 2-factor model with EXP and MAP factors; (3) a 5-factor model with separate factors for the 5 domains of the National Institute of Mental Health consensus development conference (blunted affect, alogia, anhedonia, avolition, and asociality); and (4) a hierarchical model with 2 second-order factors reflecting EXP and MAP and 5 first-order factors reflecting the 5 consensus domains.<h4>Main outcomes and measures</h4>Outcomes included CFA model fit statistics derived from symptom severity scores on the SANS, BNSS, and CAINS.<h4>Results</h4>The study population included 860 outpatients with schizophrenia (68.0% male; mean [SD] age, 43.0 [11.4] years). Confirmatory factor analysis was conducted on each scale, including 268 patients for the SANS, 192 for the BNSS, and 400 for the CAINS. The 1- and 2-factor models provided poor fit for the SANS, BNSS, and CAINS as indicated by comparative fit indexes (CFIs) and Tucker Lewis indexes (TLIs) less than 0.950, RMSEAs that exceeded the 0.080 threshold, and WRMRs greater than 1.00. The 5-factor and hierarchical models provided excellent fit, with the 5-factor model being more parsimonious. The CFIs and TLIs met the 0.95 threshold and the 1.00 threshold for both factor models with all 3 measures. Interestingly, the RMSEAs for the 5-factor model and the hierarchical model fell under the 0.08 threshold for the BNSS and the CAINS but not the SANS.<h4>Conclusions and relevance</h4>These findings suggest that the recent trend toward conceptualizing the latent structure of negative symptoms as 2 distinct dimensions does not adequately capture the complexity of the construct. The latent structure of negative symptoms is best conceptualized in relation to the 5 consensus domains. Implications for identifying pathophysiological mechanisms and targeted treatments are discussed.
Project description:<h4>Objective</h4>Clinical Assessment Interview for Negative Symptoms (CAINS) has recently been developed to improve measurement of negative symptoms in schizophrenia. We performed a multi-center study to validate the Korean version of the CAINS (CAINS-K) and explore potential cultural variation.<h4>Methods</h4>One hundred eighty schizophrenia patients diverse in demographic and illness profile were recruited from four centers in Korea. Along with the CAINS-K, the Scale for the Assessment of Negative Symptoms (SANS), Brief Psychiatric Rating Scale (BPRS), Calgary Depression Scale for Schizophrenia (CDSS), a self-report measure of behavioral inhibition and activation (BIS/BAS) and neurocognitive tasks were administered to verify external validities.<h4>Results</h4>The CAINS-K showed high internal-consistency (0.92) and inter-rater reliability (0.77). Exploratory Factor Analysis replicated a two-factor structure of the original scale including motivation/pleasure and expression deficits dimensions. Korean patients tended to report lower pleasure compared to American patients in the prior study. The CAINS-K showed an adequate convergent validity with the SANS, negative symptoms of the BPRS, and BAS. A divergent validity was supported as the CAINS-K showed zero or only weak correlations with other symptoms of the BPRS, depression from the CDSS, and neurocognitive tasks.<h4>Conclusion</h4>The CAINS-K demonstrated high internal consistency and adequate external validities, and is expected to promote studies on negative symptoms in Korean patients with schizophrenia.
Project description:The Clinical Assessment Interview for Negative Symptoms (CAINS) was designed in accordance with the recent theory and research in social affective neuroscience and to address the psychometric and conceptual limitations of other instruments assessing negative symptoms. The present study aimed to provide a large-scale validation of the CAINS in China and examine its applicability and validity evidence across the schizophrenia spectrum. Using confirmatory factor analysis, our results replicated the original findings in the US development samples that the CAINS possesses a stable 2-factor structure, namely "motivation/pleasure" and "expression". We also found significant correlations between the CAINS and other negative symptom measures. The CAINS demonstrated good discriminant validity in differentiating negative symptoms in people with schizophrenia, nonpsychotic first-degree relatives and people with social anhedonia. People with schizophrenia exhibited significantly higher CAINS subscale scores than first-degree relatives and healthy controls. In addition, first-degree relatives had higher "motivation/pleasure" scores than healthy controls. The "motivation/pleasure" subscale scores of individuals with social anhedonia were also significantly higher than healthy controls.
Project description:OBJECTIVE:This study aimed to evaluate the factor structure of the Chinese version of the 22-item Zarit Burden Interview (ZBI) among family caregivers of patients with schizophrenia in China. METHODS:Using one-stage cluster-sampling design, 324 primary caregivers of patients with schizophrenia in Ningxiang County, Hunan Province, China, completed the Zarit Burden Interview face-to-face. Confirmatory factor analysis (CFA) was first performed based on existing models to check model fit. Owing to an unsatisfactory result of CFA, exploratory factor analysis (EFA) was then conducted to explore a new factor structure, and a subsequent CFA was run to examine its model fit. RESULTS:The CFA results showed that none of the existing models fit the data reasonably well. The EFA results suggested five dimensions: negative emotion (10 items), interpersonal relationship (4 items), time demand (3 items), patient's dependence (2 items) and self-accusation and guilt (2 items). The following CFA confirmed the five-factor solution in this study, and the goodness-of-fit for this model fell within the acceptable range. The overall internal consistency (Cronbach's alpha) was 0.88, and the internal consistency coefficients of individual dimensions were 0.68 to 0.84. CONCLUSION:This study supported a 22-item ZBI scale, with a five-factor structure when applied to Chinese caregivers of patients with schizophrenia.
Project description:A major barrier to developing treatments for negative symptoms has been measurement concerns with existing assessment tools. Fulfilling the top recommendation of the National Institute of Mental Health's Consensus Development Conference on Negative Symptoms, the Clinical Assessment Interview for Negative Symptoms (CAINS) was developed using an iterative, empirical approach, and includes items assessing motivation, pleasure, and emotion expression. The authors employed multiple analytic techniques to develop the CAINS and here provide final development and validation results.The CAINS structure, interrater agreement, test-retest reliability, and convergent and discriminant validity were assessed in a large and diverse sample of 162 outpatients with schizophrenia or schizoaffective disorder recruited from four sites.Three items with poor psychometric properties were removed, resulting in a 13-item CAINS. The CAINS factor structure was replicated, demonstrating two modestly correlated scales: expression (four items) and motivation/pleasure (nine items). The scales demonstrated good internal consistency, test-retest stability, and interrater agreement. Strong convergent validity was demonstrated by linkages with other negative symptom measures, self-report scales of sociality, pleasure, and motivation, and coded facial expressions. Discriminant validity was shown by independence from depression, medication side effects, and cognition. Notably, the CAINS scales were related to real-world vocational, independent living, and social/familial functioning.The CAINS is an empirically developed and evaluated measure of negative symptoms. Findings indicate that the CAINS is brief yet comprehensive and employable across a wide range of research and clinical contexts.
Project description:Although previous findings identified an association between C-reactive protein (CRP) levels, and impaired cognitive functions in patients with schizophrenia (SZ), little is currently known about the relationship between inflammation, cognition, and sex in SZ. The current study aimed to explore the association between peripheral inflammation and cognitive impairment in SZ as a function of sex. The sample included 132 clinically stable patients with SZ, of whom 82 were males (62.1%) and 50 females (37.9%). Sociodemographic data were collected, an accurate assessment was performed using the Positive and Negative Syndrome (PANSS), Clinical Assessment Interview for Negative Symptoms (CAINS), and Calgary Depression (CDS) scales, and the MATRICS Consensus Cognitive Battery (MCCB), and CRP levels were tested. A Pearson correlation and multiple regression analyses, including potential confounding factors, were performed. We found an inverse association between CRP levels and performance on visual learning (r?=?? 0.386, p?=?0.006) domain in female patients only, whereas no correlations were found in males. The regression model for women retained age (??=?? 0.319, p?=?0.017), the CAINS-MAP score (??=?? 0.247, p?=?0.070), and the CRP (??=?? 0.321, p?=?0.013) as predictors of visual learning. Our results suggest the possible existence of sex-specific modulation of the association between systemic inflammation and the cognitive features of the illness.
Project description:<b>Background:</b> Cognitive dysfunction is considered a core feature among schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). Despite abundant literature comparing cognitive dysfunction among these disorders, the relationship between cognitive dysfunction and symptom dimensions remains unclear. The study aims are a) to identify the factor structure of the BPRS-18 and b) to examine the relationship between symptom domains and cognitive function across SZ, BD, and MDD. <b>Methods:</b> A total of 716 participants [262 with SZ, 104 with BD, 101 with MDD, and 249 healthy controls (HC)] were included in the study. One hundred eighty participants (59 with SZ, 23 with BD, 24 with MDD, and 74 HC) completed the MATRICS Consensus Cognitive Battery (MCCB), and 507 participants (85 with SZ, 89 with BD, 90 with MDD, and 243 HC) completed the Wisconsin Card Sorting Test (WCST). All patients completed the Brief Psychiatric Rating Scale (BPRS). <b>Results:</b> We identified five BPRS exploratory factor analysis (EFA) factors ("affective symptoms," "psychosis," "negative/disorganized symptoms," "activation," and "noncooperation") and found cognitive dysfunction in all of the participant groups with psychiatric disorders. Negative/disorganized symptoms were the most strongly associated with cognitive dysfunctions across SZ, BD, and MDD. <b>Conclusions:</b> Our findings suggest that cognitive dysfunction severity relates to the negative/disorganized symptom domain across SZ, BD, and MDD, and negative/disorganized symptoms may be an important target for effective cognitive remediation in SZ, BD, and MDD.
Project description:Negative symptoms in schizophrenia are related to impaired functioning. The presence of negative symptoms in early phases of psychosis in individuals at clinical risk is receiving increased attention.We evaluated comprehensively a sample of 92 young people (age range 15-25) applying the Clinical Assessment Interview for Negative Symptoms (CAINS), adapted for youth. Individuals at clinical high risk (CHR, n=29) were compared to individuals with schizophrenia (SZ, n=31) and normal controls (NC, n=32). In addition to the CAINS, participants were assessed with the Structured Interview for Prodromal Syndromes (SIPS), enabling examination of the relations among scales, as well as the Penn Computerized Neurocognitive Battery (CNB), to examine association with cognitive performance, and the Global Assessment of Function (GAF) to assess overall functioning.The CHR group was intermediate to SZ and NC on nearly all clinical measures. Negative symptoms on the CAINS correlated better with negative than with other symptoms on the SIPS and were associated with neurocognitive deficits and poorer functioning.This study illustrates the feasibility of in-depth evaluation of negative symptoms in youth and indicates that these symptoms are present already in the at-risk state and relate to impaired cognition and functioning.
Project description:Progress in the development of new pharmacological and psychosocial treatments for the negative symptoms of schizophrenia is impeded by limitations of available assessment instruments. The multi-site Collaboration to Advance Negative Symptom Assessment in Schizophrenia (CANSAS) was established to develop and validate a new clinical rating scale using a transparent, iterative, and data-driven process. The Clinical Assessment Interview for Negative Symptoms (CAINS) was designed to address limitations of existing measures and assess consensus-based sub-domains, including asociality, avolition, anhedonia, affective blunting, and alogia. The structure and psychometric properties of the CAINS were evaluated in a sample of 281 schizophrenia and schizoaffective outpatients at four sites. Converging structural analyses indicated that the scale was comprised of two moderately correlated factors - one reflecting experiential impairments (diminished motivation and enjoyment of social, vocational, and recreational activities) and one reflecting expressive impairments (diminished non-verbal and verbal communication). Item-level analyses revealed generally good distributional properties, inter-rater agreement, discriminating anchor points, and preliminary convergent and discriminant validity. Results indicate that the CAINS is a promising new measure for quantifying negative symptoms in clinical neuroscience and treatment studies. Results guided item modification or deletion, and the reliability and validity of the revised, shorter version of the CAINS is in the final phase of development within the CANSAS project.
Project description:This article presents a Polish adaptation of the Motivational Postures (Towards Taxes) Questionnaire (MPQ). The MPQ is based on the concept of five tax-related motivational postures (Commitment, Capitulation, Resistance, Disengagement and Game Playing) and consists of 29 items. Three studies validating the Polish version of the MPQ are presented. The first study was conducted with a translated version of the original questionnaire and aimed to verify the factorial validity of this version using confirmatory factor analysis (CFA). Since the factor structure revealed on Australian sample was not reproduced, exploratory factor analysis (EFA) was conducted. Study 2 used CFA to confirm the new structure of the modified version of the questionnaire evident from the Study 1 EFA, and also estimated the reliability and internal validity of the modified version. This resulted in a questionnaire consisting of 20 items and five scales (Moral Duty, Capitulation, Active Resistance, Disengagement and Pleasant Games). The third study tested the questionnaire's construct validity. A theoretical interpretation of the scale is provided.