Dimensionality, psychometric properties and population-based norms of the German version of the Revised Acquired Capability for Suicide Scale (ACSS-FAD).

The aim of the present study was the validation of the Acquired Capability for Suicide Scale-Fearlessness about Death (ACSS-FAD) in a large population sample to further establish its reliability and validity, and to provide norm values. We assessed the ACSS-FAD, measures of depression, history of suicidal behavior, and anxiety in a representative sample of the German population (N=2513) and analyzed its dimensionality, invariance across sex and construct validity by means of confirmatory factor analysis, correlational analysis and analysis of variance. The one-factorial structure achieved satisfactory model fit after introducing several correlating error terms. Across sex, partial scalar invariance could be established. Depression and anxiety showed negative associations with the ACSS-FAD while no relation with past suicidal behavior was found. Because mean scores in the ACSS-FAD were affected by sex and age group, sex and age-specific norm values were calculated. Our findings support the one-factorial structure of the ACSS-FAD when the measurement model is slightly modified, pointing out the need of revising the wording of some items. The validity of the measure should be further examined in clinical samples.