The Efficacy and Effectiveness of Online CBT - Jeroen Ruwaard

20 Chapter 2. Online CBT of Work-Related Stress2.2.4 MeasuresThe primary outcome measure was the Stress subscale from the Depression AnxietyStress Scales (DASS-42: Lovibond & Lovibond, 1995; Dutch version: de Beurs, vanDyck, Marquenie, Lange, & Blonk, 2001). Secondary measures were the Depressionand Anxiety subscales from the DASS and the Emotional Exhaustion subscale of theDutch version of the Maslach Burnout Inventory - General Survey (MBI-GS: Maslach,Jackson, & Leiter, 1996; Dutch version by Schaufeli & van Dierendonck, 2000).DASS. The DASS is a self-report instrument that assesses depressive symptoms,physical anxiety (fear), and mental stress (nervous tension). It contains 42 items,14 per subscale, that relate to the experience of symptoms in the past week. Theitems are measured on a 4-point scale ranging between 0 (”did not apply to me”)to 3 (”applied to me very much, or most of the time”). Higher scores denote lessfavourable conditions.All subscales of the Dutch adaptation are characterized by good internal consistencies(Cronbach’s α between .94 and .97, present sample: .86 to .92). Test-retestreliabilities for the Depression, Anxiety and Stress scale are r = .75, r = .89 and r =.79, respectively (de Beurs et al., 2001) . Clinical cut-off scores of c = 12 and c = 5 fordepression and anxiety are recommended by Nieuwenhuijsen, de Boer, Verbeek, Blonk,and van Dijk (2003). The corresponding percentile score of stress (14) observed in alarge (N = 1771) non-clinical sample in the UK (Crawford & Henry, 2003) was usedas the clinical cut-off in this study.MBI-GS Emotional Exhaustion. The MBI-GS is a self-report questionnaire to assessburnout across professional occupations. The Emotional Exhaustion subscale assessesemotional fatigue, i.e., the feeling of being ”worn-out”. The scale contains five itemsthat are measured on a 7-point scale scored from 0 to 6, where higher scores indicatehigher levels of emotional exhaustion. The internal consistency of the subscale rangesbetween .84 ≤ α ≤ .90 (present sample: α = .84). The 8-month test-retest reliabilityis satisfactory (.58 ≤ r ≤ .85). Well-established clinical cut-off scores are unavailablefor the Exhaustion scale. To indicate burnout, Brenninkmeijer and Van Yperen (2003)recommend a cut-off score of 2.67, which was used in the present study. With this