Psychometric testing of a Swedish version of the Apathy Evaluation Scale

Abstract

Background: Apathy, a prevalent and clinically relevant symptom in neurodegenerative disease, is often evaluated by the instrument Apathy Evaluation Scale (AES). However, this instrument has not been translated into Swedish, halting clinical and research efforts. Furthermore, previous studies lack analyses of some basic properties, such as the legitimacy of a total score, or have analysed dimensionality by questionable methods.

Aim: To translate and psychometrically evaluate a Swedish version of the AES.

Method: The AES was translated, and its psychometric properties were tested in the Swedish BioFINDER study, including cognitively well elderly, and subjects with mild cognitive or parkinsonian symptoms. Psychometric analyses were conducted according to classical test theory (CTT) and aimed to resemble those performed in the English original study by Marin et al. in 1991. Dimensionality was additionally analysed on a matrix of polychoric correlations and parallel analyses.

Results: Data indicate that the Swedish AES performs satisfactorily regarding data completeness, scaling assumptions, targeting, and reliability. Principal component analyses (with parallel analysis) of polychoric correlation matrices identified a single component. Convergent and discriminative validity correlations accorded with a priori expectations.

Conclusions: The study provides initial support that this Swedish AES performs similarly to the English original, and exhibits acceptable psychometric properties according to CTT, including supported unidimensionality, and may be adopted for use in clinical and research settings.

Keywords:

• Apathy
• Apathy Evaluation Scale (AES)
• neurodegenerative disease
• neuropsychiatric assessment
• psychometrics

View correction statement:

Correction to: M. Johansson et al., Psychometric testing of a Swedish version of the Apathy Evaluation Scale

Acknowledgements

The authors wish to thank the study subjects for their participation. We would also like to express our gratitude to Ida Friberg, Johanna Fredlund, Karin Nilsson, Katarina Johansson, and Malin Otthén for assistance in data collection.

The study was supported by the European Research Council, the Swedish Research Council, the Strategic Research Area MultiPark at Lund University, the Crafoord Foundation, the Swedish Brain Foundation, The Swedish Alzheimer foundation, Gorthon stiftelsen, Kockska stiftelserna, Kristianstad University, and the Swedish federal government under the ALF agreement. The funding sources had no role in the design and conduct of the study, in the collection, analysis, interpretation of the data, or in the preparation, review, or approval of the manuscript.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

The study was supported by the European Research Council [grant number 311292], the Swedish Research Council [grant number K2014-62X-22525-01-4], the Strategic Research Area MultiPark at Lund University, the Crafoord Foundation, the Swedish Brain Foundation [grant number FO2015-0035], The Swedish Alzheimer foundation, Gorthon stiftelsen [grant number 2014-151], Kockska stiftelserna, Kristianstad University, and the Swedish federal government under the ALF agreement. The funding sources had no role in the design and conduct of the study, in the collection, analysis, interpretation of the data, or in the preparation, review, or approval of the manuscript.