Objective measurement of chronic pain by a complex concentration test

37 Patients report that the more intense chronic pain is, the more it lowers concentration. Using different approaches, various studies revealed deficits in general cognitive functioning caused by chronic pain. Impairments were found e.g. in working memory capacity, attention and concentration (Crombez, Eccleston, Baeyens, & Eelen, 1996, 1997; Dick, Eccleston, & Crombez, 2002; Dick & Rashiq, 2007; Eccleston, 1994, 1995; Eccleston & Crombez, 1999; Grace, Nielson, Hopkins, & Berg, 1999; Grigsby, Rosenberg & Busenbark, 1995; Hart, Martelli, & Zasler, 2000). In addition, chronic pain occurred with impaired attention and concentration sustained over a longer period of time (e.g. Eccleston, 1994, 1995; Roelofs, Crombez, Peters, Verschuere, & Vlaeyen, 2005). The present study examines whether a complex concentration test is suitable to describe the relation of cognitive deficit and chronic pain. This would facilitate the assessment of the extent of impairment of an individual, for example, to decide on pension entitlement. Concentration is defined as non-automated coordination of action parts and their monitoring in a conscious and intentional way (Westhoff & Hagemeister, 2005). Concentrated work demands working as quickly as possible and at the same time accurately, something which people experience as difficult and tiring. This can be measured by concentration tests. Such a test requires coordination of perceptuomotor activity, continuous monitoring of performance, and maintenance of an optimal balance between speed and accuracy over prolonged time periods (van Breukelen, 1989). Usual concentration tests have only one type of stimuli and measure only speed of concentrated work reliably. In contrast, the Complex Concentration Test (Westhoff, 2005) consists of three subtests with different types of stimuli and includes percentage of concentration as a measure of concentration. Concentration tests with verbal, numerical as well as figural subtests are more informative (Westhoff & Scholz, 2007), being closer to requests in daily life. Percentage of concenAnja Berg, Department of Psychology, Technische Universität Dresden, Klinische Psychologie und Psychotherapie, Hohe Str. 53, 01062 Dresden, Germany. E-mail: [email protected] (the address for correspondence); Karen Oster, Department of Psychology, Technische Universität Dresden, 01062 Dresden, Germany; Herbert Janig, Department of Psychology, Alps-Adria University Klagenfurt, Universitätsstrasse 65, 9020 Klagenfurt, Austria; Rudolf Likar, Pain Ambulance, Department of Anaesthesia Clinic, General Hospital Klagenfurt, St. Veiter Str. 47, 9020 Klagenfurt, Austria; Wolfgang Pipam, Department of Psychology, Alps-Adria University Klagenfurt, Universitätsstrasse 65, 9020 Klagenfurt, Austria; Anja Scholz, Department of Psychology, Technische Universität Dresden, 01062 Dresden, Germany; Karl Westhoff, Department of Psychology, Technische Universität Dresden, 01062 Dresden, Germany. Objective measurement of chronic pain by a complex concentration test