Validating the German version of the entrapment scale among suicidal psychiatric inpatients

Abstract

Introduction

Entrapment, the feeling of being trapped by external (EE) or internal (IE) circumstances, is an important transdiagnostic construct that is associated with both the development of depressiveness and suicide ideation. Entrapment can be validly assessed by the original English version of the Entrapment Scale (ES). So far, the German version of the Entrapment Scale has been psychometrically examined only once and exclusively in a non-clinical sample. In the present study we therefore examined whether the German version of the Entrapment Scale (ES-d) is a valid and reliable instrument for measuring entrapment in a clinical sample.

Methods

The study represents a secondary analysis of a large multicentre project that investigated risk factors for suicide ideation and suicidal behaviour in a longitudinal design. The analyses are based on data from 287 patients who were admitted to hospital for a recent suicide attempt or an acute suicidal crisis. The factorial validity of the ES-d is tested by means of a confirmatory factor analysis (CFA). The internal consistency of the scale as well as its retest reliability are reported. Convergent validity (DESC, BSS, BHS), discriminant validity (PMH), and predictive validity with regard to suicide ideation and depression were examined at 6-month follow-up.

Results

The results confirm the two-factorial structure of ES-d, after three items were removed from the scale with a good internal consistency for external entrapment (EE: α = 0.84) as well as internal entrapment (IE: α = 0.85). The ES-d also showed good convergent (EE-DESC: r = 0.537. EE-BSS: r = 0.438, EE-BHS: r = 0.447; IE-DESC: r = 0.618, IE-BSS: r = 0.472, IE-BHS: r = 0.528) and discriminant (EE: r = -0.459, IE: r= -0.531) validity. Both the retest reliability (ES-d: r = 0.26, EE: r = 0.26, IE: r = 0.27) and the predictive validity prove to be low.

Discussion

The two-factorial structure of the Entrapment Scale was confirmed, however challenging the results of the previous validation of the German version, which had previously reported a single-factor structure of the scale based on a non-clinical sample. The German version of the Entrapment Scale is a valid and reliable instrument for measuring entrapment in a high-risk population.