Muscle Dysmorphic Disorder Inventory (MDDI): Validation of a German version with a focus on gender

Abstract

Muscle dysmorphia (MD) is a condition that is characterized by body image disturbance, a drive for muscularity and excessive exercising. It leads to considerable functional impairment. Most previous studies focused on male samples. The study aimed to validate a German version of the Muscle Dysmorphic Disorder Inventory (MDDI) in order to make the instrument available in German speaking countries. We further aimed to explore for gender differences in the MDDI factors (measurement invariance) and to assess the relationship between MD and positive dimensions of body experience as well as exercise dependence. 394 participants (53% females, mean age 24.3 years) took part in an internet-based survey. The three-factor structure of the English version of the MDDI was replicated, independent of gender (multi group CFA; Base model TLI = .961; CFI = .970). Cronbach´s alpha was .81-.84 for the subscales and .75 for the MDDI total score. MD was associated with exercise dependence and negatively correlated with dimensions of positive body experience, which can be considered relevant for satisfying relationships and a positive sense of self: e.g. body contact and sexual fulfillment. Men and women showed differences in two subscales of the MDDI (appearance intolerance, drive for size). Testing for measurement invariance resulted in weak invariance: Equivalent factor structure for men and women, but significantly different loadings and coefficients. No statistically significant difference in the MDDI total score was found. The findings suggest good psychometric properties of the German version of the MDDI. Future studies should address the question of cut-off scores and norms for different samples as well as a possible overlap between MD and eating disorder psychopathology in women.

An empirically derived recommendation for the classification of body dysmorphic disorder: Findings from structural equation modeling

“…The Muscle Dysmorphia Disorder Inventory (MDDI; [45]; German version; [46]) is a 13-item measure assessing symptoms associated with MD on three subscales (Drive for Size, Appearance Intolerance, Functional Impairment). Each item is rated on a 5-point Likert scale ranging from 1 "never" to 5 "always".…”

Die deutschsprachige Fassung des Muscle Dysmorphia Inventory: Evaluation der psychometrischen Kennwerte in männlichen Stichproben

“…Verglichen mit verwandten Verfahren, z. B. dem MDDI [11,12], ermöglicht das MDI die Erfassung eines umfassenderen Symptombildes, insbesondere hinsichtlich eines veränderten Ernährungsverhaltens sowie der Nutzung leistungssteigernder Substanzen. Die Anwendung des MDI in klinisch-psychologischer Forschung, Diagnostik und Therapie, ggf.…”

“…Für die weitere Erforschung, die Diagnostik und die Therapie der MD ist die Bereitstellung valider und reliabler Fragebogeninstrumentenotwendig.DiedreiamhäufigstenverwendetenSelbstbeurteilungsfragebögen zur quantitativen Erfassung von MD-typischen Einstellungs-und Verhaltensmerkmalen sind die Muscle Appearance Satisfaction Scale (MASS; [9]) sowie das Muscle Dysmorphia Inventory (MDI; [10]), gefolgt von dem Muscle Dysmorphic Disorder Inventory (MDDI; [11]) (vgl. [8]), wobei nur für Letzteres eine validierte deutschsprachige Übersetzung vorliegt [12] [10,14]…”

Community norms of the Muscle Dysmorphic Disorder Inventory (MDDI) among cisgender sexual minority men and women

“…Muscle dysmorphia (MD), currently diagnosed using a specifier for Body Dysmorphic Disorder (BDD) in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5, American Psychiatric Association, 2013), is characterized by the pathological pursuit of muscularity and a preoccupation with one's body size as not being large enough [1,2]. The condition is associated with numerous behavioral disturbances, including excessive exercise training, rigid diets, disordered eating patterns, and anabolic steroid use [3][4][5]. Individuals with MD commonly report that they have little to no control over these behaviors and have been found to exhibit poor insight related to these behaviors [6].…”

“…Functional impairment in particular represents a crucial element of the disorder that certain other measures fail to assess [21]. The MDDI has been psychometrically examined in diverse samples of menspanning multiple languages, countries, and demographicswith results suggesting that the MDDI scores demonstrate reliability and validity across a variety of populations [5,9,[22][23][24][25][26]. However, there remains a lack of published normative data for the MDDI, including in at-risk populations, such as cisgender sexual minority people, limiting the interpretability of scores on the measure in certain groups.…”