The Four-Dimensional Symptom Questionnaire (4DSQ): measuring distress and other mental health problems in a working population BEREND TERLUIN$ w , WILLEM VAN RHENEN%, WILMAR B. SCHAUFELI§ and MARTEN DE HAAN$ $ Department of General Practice, Institute for Research in Extramural Medicine, VU University Medical Centre, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands % Coronel Institute, University of Amsterdam, Amsterdam, The Netherlands, and Department of Occupational Health Services, ArboNed, Utrecht, The Netherlands § Research Institute for Psychology & Health, Utrecht University, Utrecht, The Netherlands Keywords: Four-Dimensional Symptom Questionnaire; 4DSQ; Distress; Depression; Anxiety; Somatiza- tion; Occupational stress; Psychometric properties. In non-clinical (working) populations it is important to differentiate between general distress, on the one hand, and psychiatric symptoms */depression, anxiety and somatization */on the other hand. The Four-Dimensional Symptom Questionnaire (4DSQ) is a new instrument that measures these four symptom dimensions (Terluin, 1996). This study aimed to investigate the psychometric properties of the 4DSQ in a working population. A postal stress and health survey was sent to all employees of a Dutch telecom company, 51% of whom responded (N  /3852). The mailing included the 4DSQ, a set of questionnaires concerning job stress (e.g. psychological demands), coping style (e.g. problem- focused coping, avoidant coping), and indicators of strain (e.g. emotional exhaustion, fatigue). Cronbach’s a for the four sub-scales of the 4DSQ ranged from .79 to .90. Factor analysis showed four factors corresponding to the four scales of the 4DSQ: distress, depression, anxiety, and somatization. The validity of the 4DSQ was assessed using (partial) correlations with job stress, coping, and strain. As expected, the distress scale showed the strongest correlations with the indicators of strain, as well as with job stress and coping. In conclusion, the 4DSQ is a reliable and valid instrument that can be used in a working population to distinguish between stress-related symptoms and psychiatric illness. 1. Introduction 1.1. Background Psychological health complaints are highly prevalent, both in the community and in general medical settings (Goldberg & Huxley, 1992). Based on data obtained from screening questionnaires, such as the General Health Questionnaire (GHQ; Goldberg & Williams, 1988), Verhaak (1995) reported the prevalence of psychological distress in the western Work & Stress ISSN 0267-8373 print/ISSN 1464-5335 online # 2004 Taylor & Francis Ltd http://www.tandf.co.uk/journals/ DOI: 10.1080/0267837042000297535 w Author for correspondence. e-mail: b.terluin@vumc.nl WORK & STRESS, JULY 2004, VOL. 18, NO. 3, 187  /207