Back to Journals » Neuropsychiatric Disease and Treatment » Volume 13

Construct validity of the Depression and Somatic Symptoms Scale: evaluation by Mokken scale analysis

Authors Chou YH, Lee CP, Liu CY, Hung CI

Received 3 August 2016

Accepted for publication 14 December 2016

Published 23 January 2017 Volume 2017:13 Pages 205—211


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 4

Editor who approved publication: Professor Wai Kwong Tang

Ya-Hsin Chou,1 Chin-Pang Lee,1,2 Chia-Yih Liu,1,2 Ching-I Hung1,2

1Department of Psychiatry, Chang-Gung Memorial Hospital at Linkou, 2School of Medicine, Chang Gung University College of Medicine, Taoyuan, Taiwan

Objective: Previous studies of the Depression and Somatic Symptoms Scale (DSSS), a free scale, have been based on the classical test theory, and the construct validity and dimensionality of the DSSS are as yet uncertain. The aim of this study was to use Mokken scale analysis (MSA) to assess the dimensionality of the DSSS.
Methods: A sample of 214 psychiatric outpatients with mood and anxiety disorders were enrolled at a medical center in Taiwan (age: mean [SD] =38.3 [10.5] years; 63.1% female) and asked to complete the DSSS. MSA was used to assess the dimensionality of the DSSS.
Results: All 22 items of the DSSS formed a moderate unidimensional scale (Hs=0.403), supporting its construct validity. The DSSS was divided into 4 subscales (Hs ranged from 0.35 to 0.67), including a general somatic scale (GSS), melancholic scale (MS), muscular pain scale (MPS), and chest symptom scale (CSS). The GSS is a weak reliable Mokken scale; the other 3 scales are strong reliable Mokken scales.
Conclusion: The DSSS is a psychometrically sound measure of depression and somatic symptoms in adult psychiatric outpatients with depression or anxiety. The summed score of the DSSS and its 4 subscales are valid statistics. Further research is required for replication of the 4 subscales of the DSSS.

Keywords: depression, somatization, Mokken scale analysis, item response theory, construct validity

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]