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

Juan F Rodríguez-Testal,Miguel Ruíz-Veguilla,Cristina Senín-Calderón,Salvador Perona-Garcelán,Sonia Dollfus,Jesús García-Martínez,María Valdés-Díaz

doi:10.1186/s12888-019-2314-1

Abstract

BackgroundNegative symptoms (NS) may be observed in the general population in an attenuated form and in high-risk mental states. However, they have been less studied in the general population than positive symptoms, in spite of their importance at the insidious onset of schizophrenia and their appearance before positive symptoms. This study aimed to analyze the empirical structure of the Spanish version of the Self-Evaluation of Negative Symptoms (SNS) Scale and find its psychometric properties and invariance of measurement across sex and age in a sample of adolescents.MethodsThe sample consisted of 4521 adolescents (53.6% female) from 11 to 18 years of age.ResultsConfirmatory Factor Analysis of the SNS confirmed an internal structure of five first-order factors by the characteristic dimensions of NS: avolition, social withdrawal, diminished emotional range, anhedonia, alogia, and one second-order factor which includes the total NS score. Multi-group confirmatory factor analysis showed that the scale was invariant across sex and age. Total scale reliability was adequate. A strong relationship was found between the SNS with depressive symptomatology, moderate with ideas of reference and low with aberrant salience. Conclusion: The results back use of the Spanish version of the SNS scale for detection of NS in the general population of adolescents.

Highlights

Negative symptoms (NS) may be observed in the general population in an attenuated form and in high-risk mental states
The items with the lowest percentage of positive answers were related to the social withdrawal factor (Items 3 and 4) and anhedonia (Items 17 and 18)
Study of NS such as Psychotic-Like Experiences (PLEs) during adolescence could pose an advantage for properly characterizing the complex process that could culminate in development of psychosis

Summary

Introduction

Negative symptoms (NS) may be observed in the general population in an attenuated form and in high-risk mental states. They have been less studied in the general population than positive symptoms, in spite of their importance at the insidious onset of schizophrenia and their appearance before positive symptoms. Negative symptoms (NS) are defined as the diminution in or absence of affective-motivational responses typical of adapted functioning [1]. They are more frequent, longlasting, and avolition/apathy/amotivation is more prominent than the expressive component. Outside of this spectrum, they tend to be transitory and secondary [15]

Objectives

Results

Discussion

Conclusion