Spanish validation of the self-evaluation of negative symptoms scale SNS in an adolescent population

Negative Symptom Inventory-Self-Report (NSI-SR): Initial development and validation

Negative symptoms (i.e., anhedonia, avolition, asociality, blunted affect, alogia) are frequently observed in the schizophrenia-spectrum (SZ) and associated with functional disability. While semi-structured interviews of negative symptoms represent a gold-standard approach, they require specialized training and may be vulnerable to rater biases. Thus, brief self-report questionnaires measuring negative symptoms may be useful. Existing negative symptom questionnaires demonstrate that this approach may be promising in schizophrenia, but no measure has been devised for use across stages of psychotic illness. The present study reports initial psychometric validation of the Negative Symptom Inventory-Self-Report (NSI-SR), the self-report counterpart of the Negative Symptom Inventory-Psychosis Risk clinical interview. The NSI-SR is a novel transphasic negative symptoms measure assessing the domains of anhedonia, avolition, and asociality. The NSI-SR and related measures were administered to two samples: 1) undergraduates (n = 335), 2) community participants, including: SZ (n = 32), clinical-high risk for psychosis (CHR, n = 25), and healthy controls matched to SZ (n = 31) and CHR (n = 30). The psychometrically trimmed 11-item NSI-SR showed good internal consistency and a three-factor solution reflecting avolition, asociality, and anhedonia. The NSI-SR demonstrated convergent validity via moderate to large correlations with clinician-rated negative symptoms and related constructs in both samples. Discriminant validity was supported by lower correlations with positive symptoms in both samples; however, correlations with positive symptoms were still significant. These initial psychometric findings suggest that the NSI-SR is a reliable and valid brief questionnaire capable of measuring negative symptoms across phases of psychotic illness.

Validity and reliability of a Chinese version of the self-evaluation of negative symptoms

The negative symptoms of schizophrenia can be present at any clinical stage, but evaluating the negative symptoms always remains challenging. To screen the negative symptoms effectively, self-evaluation should be introduced. To date, professional psychiatrists used almost all of the scales available to screen the negative symptoms but could not obtain an accurate outcome. At the same time, an advanced self-assessment scale is needed to accompany the patients' self-feeling-based treatment strategies to understand their feelings about their symptoms. Hence, Chinese self-evaluation of negative symptoms (SNS) should be introduced in China. This study aims to examine the validity and reliability of the Chinese version of SNS. Two hundred patients with schizophrenia were included in this study and were evaluated entirely with the self-assessed negative symptoms by the Chinese version. The correlation analysis was performed between SNS and the Scale for Assessment of Negative Symptoms (SANS) to assess the criterion validity of SNS for screening negative symptoms. Exploratory factor analysis was used to determine the constructive validity of the SNS. Two senior professional psychiatrists were involved in this assessment based on their clinical experience and capability to define the severity of the negative symptoms. Receiver operating characteristic curve (ROC) analysis was performed to assess the cutoff point of SNS. Cronbach's alpha coefficient and intraclass correlation (ICC) coefficient were used to determine the reliability of SNS. We have the following findings: The Chinese version of SNS demonstrated a significant correlation with the SANS (r = .774, p < .05). Exploratory factor analysis demonstrated that the factor loading varies from .442 to .788. ROC analysis demonstrated that at SNS ≥ 8, the patients demonstrated a mild severity of negative symptoms, and at SNS ≥ 15, the patients demonstrated a severe severity of negative symptoms. Subsequently, 9 < SNS < 14 was defined as a moderate severity of negative symptoms. The Cronbach's alpha and ICC coefficients of the Chinese version SNS were .877 and .774, respectively. Our results showed that the acceptable validity and reliability of the Chinese version of SNS confirmed that SNS is an ideal tool for self-assessment of the negative symptoms in patients with schizophrenia.

The Self-Evaluation of Negative Symptoms in Differentiating Deficit Schizophrenia: The Comparison of Sensitivity and Specificity with Other Tools

INTRODUCTION

Psychometric properties of the Self-evaluation of Negative Symptoms (SNS) in subjects with the deficit subtype of schizophrenia (SCZ-D) have not been investigated so far. This study had the following aims: (1) to assess psychometric properties of SNS in subjects with SCZ-D and (2) to explore the usefulness of SNS, in comparison with other clinical characteristics, in screening for SCZ-D.

METHODS

Participants were 82 stable outpatients with schizophrenia, including 40 individuals with SCZ-D and 42 individuals with the non-deficit subtype (SCZ-ND).

RESULTS

Internal consistency was acceptable-to-good in both groups. Factor analysis revealed two dimensions (apathy and emotional). There were significant positive correlations of the SNS total score with the subscore of negative symptoms from the Positive and Negative Syndrome Scale (PANSS) and significant negative correlations with scores of the Social and Occupational Functioning Assessment Scale (SOFAS) in both groups, indicating good convergent validity. The following measures were found to be appropriate screening tools for differentiating SCZ-D and SCZ-ND (p < 0.001): the SNS total score (area under the curve [AUC]: 0.849, cut-off ≥16, sensitivity: 80.0%, specificity: 78.6%), the PANSS subscore of negative symptoms (AUC: 0.868, cut-off ≥11, sensitivity: 90.0%, specificity: 78.6%), and the SOFAS (AUC: 0.779, cut-off ≤59, sensitivity: 69.2%, specificity: 82.5%). Also, adding the SOFAS (cut-off ≤59) to the SNS (cut-off: ≥16) further improved sensitivity and specificity (AUC: 0.898, p < 0.001, sensitivity = 87.5%, specificity = 82.2%). Cognitive performance and age of psychosis onset were not found to be suitable measures for differentiating SCZ-D and SCZ-ND.

CONCLUSION

The present findings indicate that the SNS has good psychometric properties in subjects with SCZ-D and those with SCZ-ND. Moreover, the SNS, the PANSS, and the SOFAS might be used as screening tools for SCZ-D.

Development and Validation of the Chinese Version of the Highly Sensitive Child Scale: Understanding environmental sensitivity and depressive symptoms in adolescents

Background

Environmental sensitivity (ES) is considered a significant personality factor in the development and maintenance of depressive symptoms in adolescents. However, a clear instrument that can capture ES in Chinese adolescents is lacking. The current study aimed to investigate the psychometric properties of a Chinese version of the Highly Sensitive Child (HSC) Scale for assessing adolescent ES, and explore the potential moderation effect of ES on relationships between maternal behaviors and adolescent depressive symptoms.

Methods

In total, 2,166 students from four middle and high schools and 105 depressed adolescents completed measurements of environmental sensitivity, maternal behaviors, depressive emotions, sleep duration, and academic performance.

Results

First, exploratory factor and confirmatory factor analyses indicated that the HSC scale had a good model fit with the bifactor construct, total scale reliability was adequate-good, and measurement invariances across genders and different samples were supported. Furthermore, the results confirmed that the relationship between maternal behaviors and adolescent depressive symptoms had small effects. Compared to low environmentally sensitive adolescents, high environmentally sensitive adolescents exhibited less depressive emotions and better academic performance in the context of high-quality maternal behaviors. Low-quality maternal behaviors significantly predicted increased depressive emotions and worse academic performance in adolescents when environmental sensitivity was high. Moreover, on the contrary, maternal behaviors did not influence depressive emotions and academic performance in adolescents who were less sensitive to their environment. The relationship between maternal behaviors and adolescent depressive symptoms is influenced by different levels of environmental sensitivity.

Conclusion

Our findings support the HSC scale as a comprehensive and psychometrically robust tool to measure ES in Chinese adolescents. In addition, the present study clarifies the moderating role of environmental sensitivity underlying the relationship between maternal behaviors and adolescent depressive symptoms. It is important to consider the role of ES in prevention and intervention strategies targeting adolescent depressive symptoms.

Validation of the Turkish version of the self-evaluation of negative symptoms scale (SNS)

OBJECTIVES

The Self-Evaluation of Negative Symptoms Scale (SNS) is a self-report scale that evaluates a patient's subjective experience on all five domains of the negative symptoms. This study aimed to present the adaptation and validation study of the Turkish version of SNS(SNS-TR).

METHODS

Seventy-five patients and 50 controls were recruited for this study. After the approval of the translation, participants were asked to fill out SNS-TR by themselves. They were interviewed with the Brief Negative Symptoms Scale (BNSS), Positive and Negative Syndrome Scale (PANSS), and Calgary Depression Scale for Schizophrenia (CDSS).

RESULTS

SNS-TR showed good internal consistency in the reliability analysis with Cronbach's alpha= 0.873. Subscale-total score correlation coefficients were significant (p < 0.01). In the validity analyses, the total and subscale scores of SNS-TR showed positive correlations with the total and subscales of BNSS, with only one exception of BNSS lack of distress subscales. The total score of SNS-TR demonstrated a significant correlation with PANSS-total, PANSS-negative subscale, PANSS-general subscale, and CDSS scores. Confirmatory factor analysis showed acceptable values for the five-factor structure, similar to the original version.

CONCLUSION

To conclude, our study indicates that SNS-TR is an easily applicable self-evaluation tool with good psychometric properties for assessing negative symptoms. KEY POINTSSNS is a novel and easily applicable self-report scale for examining negative symptoms in schizophrenia patients, allowing them to evaluate their subjective experience on all five domains of the negative symptoms.It shows good internal consistency (α= 0.873) which is similar to the original version (α = 0.867).Confirmatory factor analysis scores were found in acceptable ranges and SNS-TR confirm the five-factor structure.Using this scale in clinical practice would empower both the physician's examinations and patient participation through treatment and follow-up course.

Updated perspectives on the clinical significance of negative symptoms in patients with schizophrenia

INTRODUCTION

Negative symptoms in schizophrenia are associated with poor response to available treatments, poor quality of life, and functional outcome. Therefore, they represent a substantial burden for people with schizophrenia, their families, and health-care systems.

AREAS COVERED

In this manuscript, we will provide an update on the conceptualization, assessment, and treatment of this complex psychopathological dimension of schizophrenia.

EXPERT OPINION

Despite the progress in the conceptualization of negative symptoms and in the development of state-of-the-art assessment instruments made in the last decades, these symptoms are still poorly recognized, and not always assessed in line with current conceptualization. Every effort should be made to disseminate the current knowledge on negative symptoms, on their assessment instruments and available treatments whose efficacy is supported by research evidence. Longitudinal studies should be promoted to evaluate the natural course of negative symptoms, improve our ability to identify the different sources of secondary negative symptoms, provide effective interventions, and target primary and persistent negative symptoms with innovative treatment strategies. Further research is needed to identify pathophysiological mechanisms of primary negative symptoms and foster the development of new treatments.

Measuring Voluntary Control Over Hallucinations: The Yale Control Over Perceptual Experiences (COPE) Scales

Auditory verbal hallucinations (AVH) frequently cause significant distress and dysfunction, and may be unresponsive to conventional treatments. Some voice-hearers report an ability to fully control the onset and offset of their AVH, making them significantly less disruptive. Measuring and understanding these abilities may lead to novel interventions to enhance control over AVH. Fifty-two voice-hearers participated in the pilot study. 318 participants with frequent AVH participated in the validation study. A pool of 59 items was developed by a diverse team including voice-hearers and clinicians. After the pilot study, 35 items were retained. Factorial structure was assessed with exploratory (EFA, n = 148) and confirmatory (CFA, n = 170) factor analyses. Reliability and convergent validity were assessed using a comprehensive battery of validated phenomenological and clinical scales. CFA on the final 18 items supported two factors for a Methods of Control Scale (5 items each, average ω = .87), and one factor for a Degree of Control Scale (8 items, average ω = .95). Correlation with clinical measures supported convergent validity. Degree of control was associated with positive clinical outcomes in voice-hearers both with and without a psychosis-spectrum diagnosis. Degree of control also varied with quality of life independently of symptom severity and AVH content. The Yale control over perceptual experiences (COPE) Scales robustly measure voice-hearers' control over AVH and exhibit sound psychometric properties. Results demonstrate that the capacity to voluntarily control AVH is independently associated with positive clinical outcomes. Reliable measurement of control over AVH will enable future development of interventions meant to bolster that control.

Validation of a European Spanish-version of the Self-Evaluation of Negative Symptoms (SNS) in patients with schizophrenia

INTRODUCTION

Negative symptoms can be grouped into five domains: apathy/avolition, anhedonia, asociality, alogia, and affective flattening. There are few validate self-rated measures that assess these five dimensions. Therefore, this study aimed to validate the Self-Evaluation of Negative Symptoms (SNS) in Spanish patients with schizophrenia.

MATERIAL AND METHODS

Cross-sectional, validation study in 104 outpatients with schizophrenia evaluated using the Spanish version of the following scales: Clinical Assessment Interview for Negative Symptoms (CAINS), Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Scale for Schizophrenia (CGI-SCH), Personal and Social Performance (PSP), Motivation and Pleasure Scale - Self-Report (MAP-SR), 36-item Short-Form Health Survey (SF-36) and the Self-Evaluation of Negative Symptoms (SNS).

RESULTS RELIABILITY

Internal consistency (Cronbach's alpha) was 0.915. Convergent validity: The Pearson correlation coefficient between MAP-SR and SNS Total scores was 0.660 (p<0.001). For PANSS-N, the correlation was 0.437 (p<0.005) and with the CAINS-Total was 0.478 (p<0.005). Divergent validity: The Pearson correlation coefficient between SNS and PSP was r=-0.372 (p≤0.001), and with SF-36 Physical and Mental Summary Component scores were r=-0.213 (p=0.066) and r=-0.144 (p=0.219), respectively. Discriminant validity: SNS Total scores were significantly statistically different according to the severity of the negative symptomatology rated by the CGI-SCH negative scale (p<0.001).

CONCLUSION

The SNS is a reliable and valid instrument to self-rate the five domains of negative symptoms in patients with schizophrenia and seems to be appropriate for use in everyday clinical practice as a complementary measure to the evaluation performed by the clinician.

European Validation of the Self-Evaluation of Negative Symptoms (SNS): A Large Multinational and Multicenter Study

BACKGROUND

Negative symptoms are usually evaluated with scales based on observer ratings and up to now self-assessments have been overlooked. The aim of this paper was to validate the Self-evaluation of Negative Symptoms (SNS) in a large European sample coming from 12 countries. We wanted to demonstrate: (1) good convergent and divergent validities; (2) relationships between SNS scores and patients' functional outcome; (3) the capacity of the SNS compared to the Brief Negative Symptom Scale (BNSS) to detect negative symptoms; and (4) a five-domain construct in relation to the 5 consensus domains (social withdrawal, anhedonia, alogia, avolition, blunted affect) as the best latent structure of SNS.

METHODS

Two hundred forty-five subjects with a DSM-IV diagnosis of schizophrenia completed the SNS, the Positive and Negative Syndrome Scale (PANSS), the BNSS, the Calgary Depression Scale for Schizophrenia (CDSS), and the Personal and Social Performance (PSP) scale. Spearman's Rho correlations, confirmatory factor analysis investigating 4 models of the latent structure of SNS and stepwise multiple regression were performed.

RESULTS

Significant positive correlations were observed between the total score of the SNS and the total scores of the PANSS negative subscale (r = 0.37; P < 0.0001) and the BNSS (r = 0.43; p < 0.0001). SNS scores did not correlate with the level of insight, parkinsonism, or the total score of the PANSS positive subscale. A positive correlation was found between SNS and CDSS (r = 0.35; p < 0.0001). Among the 5 SNS subscores, only avolition subscores entered the regression equation explaining a lower functional outcome. The 1-factor and 2-factor models provided poor fit, while the 5-factor model and the hierarchical model provided the best fit, with a small advantage of the 5-factor model. The frequency of each negative dimension was systematically higher using the BNSS and the SNS vs. the PANSS and was higher for alogia and avolition using SNS vs. BNSS.

CONCLUSION

In a large European multicentric sample, this study demonstrated that the SNS has: (1) good psychometric properties with good convergent and divergent validities; (2) a five-factor latent structure; (3) an association with patients' functional outcome; and (4) the capacity to identify subjects with negative symptoms that is close to the BNSS and superior to the PANSS negative subscale.

Mindfulness, cognitive fusion, and self-compassion in patients with schizophrenia spectrum disordersA cross-sectional study

In the last decades, third wave approaches in cognitive-behavioral therapies (CBT) have shown effectiveness in treating several mental disorders, including schizophrenia spectrum disorders (SSD). Three crucial processes associated with clinical changes in patients include mindfulness, psychological flexibility (PF) and self-compassion (SC). PF is generally assessed by cognitive fusion (CF), a negative formulated key process of PF. The current study encompasses a cross-sectional design to examine the interplay of mindfulness, CF, SC and symptom severity in SSD. It was hypothesized that mindfulness is negatively correlated with symptom severity, CF mediates the negative relation between mindfulness and symptom severity, and SC moderates the link between mindfulness and CF. In total, 79 persons with SSD were recruited at the Department of Psychiatry and Neurosciences at the Charité - Universitätsmedizin Berlin. Correlations, as well as moderated mediation analyses, were performed using the analysis modeling tool PROCESS with total symptom severity and negative symptom severity as outcome variables, measured by the Positive and Negative Syndrome Scale (PANSS) and the Self-Evaluation of Negative Symptoms Scale (SNS). Results show that the moderated mediation hypothesis was confirmed for negative symptom severity assessed by SNS, however, not for total symptom severity assessed by PANSS. In general, the association between mindfulness and CF was stronger for participants with higher SC scores in our data. Future studies should investigate the relationship between mindfulness, SC, and PF regarding symptom severity in SSD in longitudinal designs while considering the impact on different outcomes and differences regarding assessment tools.

The Latent Structure of Negative Symptoms in the General Population in Adolescence and Emerging Adulthood

Negative symptoms predict adverse outcomes within psychotic disorders, in individuals at high-risk for psychosis, and in young people in the community. There is considerable interest in the dimensional structure of negative symptoms in clinical samples, and accumulating evidence suggests a 5-factor structure. Little is known about the underlying structure of negative symptoms in young people despite the importance of this developmental stage for mental health. We used confirmatory factor analysis to test the structure of parent-reported negative symptoms at mean ages 16.32 (SD 0.68, N = 4974), 17.06 (SD 0.88, N = 1469) and 22.30 (SD 0.93, N = 5179) in a community sample. Given previously reported associations between total negative symptoms and genome-wide polygenic scores (GPS) for major depressive disorder (MDD) and schizophrenia in adolescence, we assessed associations between individual subdomains and these GPSs. A 5-factor model of flat affect, alogia, avolition, anhedonia, and asociality provided the best fit at each age and was invariant over time. The results of our linear regression analyses showed associations between MDD GPS with avolition, flat affect, anhedonia, and asociality, and between schizophrenia GPS with avolition and flat affect. We showed that a 5-factor structure of negative symptoms is present from ages 16 to 22 in the community. Avolition was most consistently associated with polygenic liability to MDD and schizophrenia, and alogia was least associated. These findings highlight the value of dissecting negative symptoms into psychometrically derived subdomains and may offer insights into early manifestation of genetic risk for MDD and schizophrenia.

Validity and reliability of a Persian version of the self- evaluation of negative symptoms (SNS)

AIM

The Self-evaluation of Negative Symptoms (SNS) has been developed to allow schizophrenia patients to evaluate themselves in five dimensions of negative symptoms. The present study aimed to examine psychometric properties of the Persian version of SNS.

METHODS

A group of 50 patients with schizophrenia and a group of 50 healthy controls received the Persian-SNS. Severity of negative symptoms were evaluated by the Scale for Assessment of Negative symptoms (SANS) and the Brief Psychiatric Rating Scale (BPRS).

RESULTS

The results showed that the Cronbach's alpha for the Persian SNS was 0.95. The Persian-SNS and its subscales showed significant positive correlations with the total SANS score and SANS subscales as well as BPRS negative subscale, thus confirming the validity of the scale. Finally, the Persian-SNS showed the ability to discriminate patients with schizophrenia from healthy controls.

CONCLUSION

The acceptable properties of the Persian version of SNS demonstrated that it is a practical tool for screening negative symptoms in Persian-speaking schizophrenia patients.

Negative symptoms in schizophrenia, assessed by the brief negative symptom scale, self-evaluation of negative symptom scale, and social cognition: a gender effect

OBJECTIVE

Negative symptoms of schizophrenia can be related to social cognition. The aim was to measure a relationship between the results on the new scales for the assessment of negative symptoms such as the Brief Negative Symptom Scale (BNSS) and Self-evaluation of Negative Symptoms (SNS), and the measures of social cognition.

METHODS

The study included 80 patients (40 men, 40 women) with schizophrenia, aged 19-63 (mean 38 years), during the improvement period. They were assessed using the BNSS, SNS, Personal and Social Performance (PSP) scales, and the tests for social cognition such as the Facial Emotion Identification Test, Reading the Mind in Eyes Test, Strange Stories and Faux Pas Test.

RESULTS

Male patients obtained higher scores than females when assessed by the BNSS. No gender differences were observed for the SNS scale. Female patients scored better in the PSP and both parts of the Faux Pas test and obtained a significant correlation between the results of the SNS scale, BNSS, PSP, and the affective part of the Faux-Pas test what was not the case in males.

CONCLUSIONS

Gender differences were found in the assessment of negative symptoms by a clinical scale and the relationship between negative symptoms and social cognition.KEY POINTSFemale patients scored better in the BNSS, PSP and both parts of the Faux-Pas testGender differences were present in the assessment of negative symptoms by clinical (BNSS) but not the self-assessment (SNS) scale.Female patients obtained a significant correlation between the results of the SNS scale, BNSS, PSP, and the affective part of the Faux-Pas test what was not the case in male subjects.

Validation of the lithuanian version of the self-evaluation of negative symptoms scale (SNS)

PURPOSE

To validate the Lithuanian version of the Self-Evaluation Negative Symptoms Scale (Lith-SNS).

MATERIALS AND METHODS

A double translation from French to Lithuanian and back was performed. We included patients from in-patient and out-patient settings that had a diagnosis of paranoid schizophrenia according to ICD-10 criteria and were screened as free from acute psychotic symptoms using the Mini International Neuropsychiatric Interview (MINI). Participants were evaluated using the Brief Psychiatric Rating Scale (BRPS) and completed the Lith-SNS scale. We measured internal consistency, convergent validity, and discriminant validity of Lith - SNS comparing its scores with BPRS negative and positive symptom subscores.

RESULTS

A total of 67 participants were evaluated. Cronbach's alpha (α) for all 20 items of Lith-SNS (α = 0.82), and for the five subscores (α = 0.76) showed good internal consistency. Factor analysis showed a 2-factor solution which accounted for 70.12% of the variance with the first factor accounting for 53.3% and the second factor accounting for 16.8% of the variance. Lith-SNS total scores and all five subscores significantly correlated with BPRS negative symptoms subscores showing good convergent validity. There was a correlation between the Positive subscore of BPRS and the alogia subscore of Lith-SNS (r = 0.39, p = 0.001), but no correlations with other subscores or the total Lith-SNS score showing adequate discriminant validity.

CONCLUSIONS

Lithuanian version of SNS is a valuable tool to evaluate negative symptoms of schizophrenia with good internal consistency, convergent, and discriminant validity.

Latent structure of self-report negative symptoms in patients with schizophrenia: A preliminary study

INTRODUCTION

Negative symptoms are associated with poor outcomes and functioning. Latent structure of negative symptoms is important for identifying potential intervention targets for novel treatments. Self-report instruments have been developed to measure negative symptoms. Previous findings on latent structure of negative symptoms are inconsistently and mainly rely on clinician-rated instruments.

METHOD

We aimed to explore the latent structure of the Self-Evaluation of Negative Symptoms Scale (SNS) in 204 clinically-stable outpatients with schizophrenia. Confirmatory factor analysis (CFA) was used to compare the competing models (i.e., one-factor, two-factor and five-factor models), and estimated goodness-of-fit indexes. Other clinician-rated scales for psychopathology and medication side-effects were also collected.

RESULTS

The CFA found the five-factor model performing best, with a comparative fit index (CFI) of > 0.95, a Tucker Lewis Index (TLI) of > 0.95, and a root mean square error of approximation (RMSEA) of < 0.06. The robust chi-square difference test for the weighted least squares with mean and variance adjusted estimation (WLSMV) also indicated a significant better fit for the five-factor model.

DISCUSSION

Our preliminary findings support a five-factor latent structure of self-report negative symptoms in schizophrenia patients. Further research in this area should utilize multiple clinician-rated and self-report measures, and recruit large and homogeneous samples with schizophrenia.

EPA guidance on assessment of negative symptoms in schizophrenia

Background

During the last decades, a renewed interest for negative symptoms (NS) was brought about by the increased awareness that they interfere severely with real-life functioning, particularly when they are primary and persistent.

Methods

In this guidance paper, we provide a systematic review of the evidence and elaborate several recommendations for the conceptualization and assessment of NS in clinical trials and practice.

Results

Expert consensus and systematic reviews have provided guidance for the optimal assessment of primary and persistent negative symptoms; second-generation rating scales, which provide a better assessment of the experiential domains, are available; however, NS are still poorly assessed both in research and clinical settings.

This European Psychiatric Association (EPA) guidance recommends the use of persistent negative symptoms (PNS) construct in the context of clinical trials and highlights the need for further efforts to make the definition of PNS consistent across studies in order to exclude as much as possible secondary negative symptoms. We also encourage clinicians to use second-generation scales, at least to complement first-generation ones.

The EPA guidance further recommends the evidence-based exclusion of several items included in first-generation scales from any NS summary or factor score to improve NS measurement in research and clinical settings. Self-rated instruments are suggested to further complement observer-rated scales in NS assessment.

Several recommendations are provided for the identification of secondary negative symptoms in clinical settings.

Conclusions

The dissemination of this guidance paper may promote the development of national guidelines on negative symptom assessment and ultimately improve the care of people with schizophrenia.

Self-evaluation of negative symptoms in adolescent and young adult first psychiatric episodes

BACKGROUND

Negative Symptoms (blunted affect, alogia, anhedonia, avolition, and asociality) are usually described in schizophrenia but they are also present in other psychiatric disorders. The diagnosis and prognosis relevance of negative symptoms (NS) self-assessment during a first psychiatric episode is still unknown.

AIMS

To determine (i) the rate of self-assessed NS in a first psychiatric episode among adolescents and young adults compared to control subjects; and (ii), whether there is a difference in the prevalence of NS between schizophrenia and major depressive disorder first episodes.

METHODS

The population included patients aged 15-25 years, with no psychiatric history and no history of medication. A dimensional evaluation was assessed during hospitalization, including depressive (Hamilton Depression Scale), psychotic symptoms (Prodromal Questionnaire, 16 items) and the self-evaluation of negative symptoms (SNS scale). Prospective categorical diagnoses were updated 6 months after hospitalization. The population included 117 individuals (58 patients and 59 healthy controls).

RESULTS

Among healthy individuals, 47.5% reported at least one NS, the most reported being amotivation. After binary logistic regression, Negative Symptoms (SNS score) were associated with a diagnostic of psychiatric disorder at the 6-months follow-up (OR = 1.163, p = .001), whereas depressive symptoms and psychotic experiences were not. A SNS threshold allowed to screen first episode patients and SZ patients in the general population (assessed with ROC curve). A high prevalence of self-reported NS was observed across diagnostic boundaries in first psychiatric episodes, with a mean SNS score of 19.3 ± 7.1 for schizophrenic disorders and 20.7 ± 8.6 for depressive disorders. The prevalence of NS was not significantly different between depressive disorders and schizophrenic disorders (p > .05).

CONCLUSION

NS are an important transnosographic dimension during first psychiatric episodes among adolescents and young adults. Negative symptoms self-assessment with the SNS scale is relevant during a first psychiatric episode.

Validation of a European Spanish-version of the Self-Evaluation of Negative Symptoms (SNS) in patients with schizophrenia

INTRODUCTION

Negative symptoms can be grouped into five domains: apathy/avolition, anhedonia, asociality, alogia, and affective flattening. There are few validate self-rated measures that assess these five dimensions. Therefore, this study aimed to validate the Self-Evaluation of Negative Symptoms (SNS) in Spanish patients with schizophrenia.

MATERIAL AND METHODS

Cross-sectional, validation study in 104 outpatients with schizophrenia evaluated using the Spanish version of the following scales: Clinical Assessment Interview for Negative Symptoms (CAINS), Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Scale for Schizophrenia (CGI-SCH), Personal and Social Performance (PSP), Motivation and Pleasure Scale - Self-Report (MAP-SR), 36-item Short-Form Health Survey (SF-36) and the Self-Evaluation of Negative Symptoms (SNS).

RESULTS RELIABILITY

Internal consistency (Cronbach's alpha) was 0.915. Convergent validity: The Pearson correlation coefficient between MAP-SR and SNS Total scores was 0.660 (p<0.001). For PANSS-N, the correlation was 0.437 (p<0.005) and with the CAINS-Total was 0.478 (p<0.005). Divergent validity: The Pearson correlation coefficient between SNS and PSP was r=-0.372 (p≤0.001), and with SF-36 Physical and Mental Summary Component scores were r=-0.213 (p=0.066) and r=-0.144 (p=0.219), respectively. Discriminant validity: SNS Total scores were significantly statistically different according to the severity of the negative symptomatology rated by the CGI-SCH negative scale (p<0.001).

CONCLUSION

The SNS is a reliable and valid instrument to self-rate the five domains of negative symptoms in patients with schizophrenia and seems to be appropriate for use in everyday clinical practice as a complementary measure to the evaluation performed by the clinician.

Validation of the Arabic version of the "self-evaluation of negative symptoms" scale (SNS)

BACKGROUND

The self-evaluation of negative symptoms scale (SNS) is a new easy-to-use self-administered questionnaire allowing clinicians to understand the clinical and genetic factors affecting the negative symptoms in patients with schizophrenia. There was a need to translate and validate this scale in Arabic so that Arab-speaking patients benefit from it. Therefore, the aim of our study was to validate the Arabic version of the SNS in a sample of Lebanese patients with schizophrenia.

METHODS

The Arabic SNS was used to quantify the disability associated with negative symptoms in patients with schizophrenia (n = 206). Six weeks after completing the SNS, the participants were interviewed again to assess test-retest reproducibility. The validity was confirmed by factor analyses using the principal component analysis technique with a varimax rotation. The Positive and Negative Syndrome Scale (PANSS) was also assessed.

RESULTS

None of the items of the SNS scale were removed; all items converged over a solution of five factors that had an eigenvalue > 1, explaining a total of 66.01% of the variance (Cronbach's alpha = 0.879; test part). The mean total SNS score was 17.33 ± 8.43 for the "test", and 16.35 ± 7.50 for the "retest". The correlation coefficients between the SNS total score and the PANSS scale and subscales were as follows: total PANSS (r = 0.044; p = 0.530), positive PANSS score (r = - 0.106; p = 0.131), negative PANSS score (r = 0.204; p = 0.003), and general psychopathological PANSS score (r = 0.03; p = 0.530).

CONCLUSION

This study is the first to validate the Arabic version of the SNS in patients with schizophrenia. Using this scale would help improve treatment by correctly assessing negative symptoms, thus optimizing treatment options.