Blended versus face-to-face Cognitive Behavioral Therapy for major depression in specialized mental health care – a pilot randomized controlled trial examining health care efficiency

The health-economic analyses combine clinical outcomes with cost estimates. Measures of these primary variables are described in this section.



Clinical outcomes:

Primary clinical outcomes are 1) recovery from Depression as assessed by the Mini-International Neuropsychiatric Interview (MINI), 2) changes in Depressive symptom severity as measured by the Inventory of Depressive Symptomatology – Self Report (IDS-SR), 3) quality-adjusted life years (QALY’s), derived from the Euro Quality of Life questionnaire (EQ-5D-3L) and 4) health-related quality of life, tapped by the SF-36 Health Survey.



Cost outcomes:

Cost estimates include 1) the costs of offering the treatments and 2) Patients’ out-of-pocket costs (non-medical), such as the costs of travelling to the health services and the patients’ time costs of travelling, waiting and receiving treatment, which are determined with the standard cost prices as listed in the pertinent Dutch guideline for economic evaluation (Tan et al., 2012). Furthermore, 3) Costs stemming from health care uptake, including costs of medication, and 4) Costs stemming from productivity losses due to absenteeism and lesser efficiency while at work (presenteeism) are assessed with The Trimbos/iMTA questionnaire for Costs associated with Psychiatric Illness (TiC-P; Hakkaart – van Roijen et al., 2002).

To further evaluate bCBT compared to CBTAU, a number of explorative measures are administered.



The Quick Inventory of Depressive Symptomatology (QIDS-SR; Rush et al., 2003), a shortened version of the IDS-SR, will be administered monthly during the study period to more closely monitor the depressive symptom change trajectory (at weeks 4, 8, 12, 16, 24, 28).

The five item version of The Mastery Scale (Pearlin, & Schooler, 1987) is administered at every assessment moment (T0-T3) to assess changes in locus of control.

The 12-item version of the Work Alliance Inventory (WAV-12, Reynolds et al., 1995; Andrusyna et al., 2001; Stinckens et al., 2009) is used to let patients rate the quality of the work alliance between patient and therapist at T1 (week 10). T
The depression scale of the Cognition Checklist (Beck et al., 1987) will be used to assess the frequency of automatic thoughts relevant to depression, at T0-T3. Demographic characteristics such as age, sex, education, employment and marital status will be collected with a general demographic questionnaire. Additional questions are asked concerning clinical depression characteristics such as age of onset, number of months depressed in past 4 years, duration of current episode, medical illnesses and treatment status. In addition, patients indicate their treatment preference (BCBT / CBTAU). Finally, participants are asked about their computer use: number of hours spent behind a computer and reasons for use. Patient evaluations The Client Satisfaction Questionnaire-8 (CSQ-8; Larsen et al., 1979) will be administered at week 30 (T3).

The System Usability Scale (SUS, Brooke, 1996) will be administered at week 20 amongst the participants randomized to the bCBT group. The SUS consists of 10 questions with 5 response options, ranging from 0 (strongly disagree) to 4 (strongly agree).The total scores are converted to a scale ranging from 0 to 100. Higher scores are indicative of higher usability of the online platform that is used for the Internet sessions in the blended therapy.

Process data Data for process analyses are obtained from the administration of the participating mental health care institutions and through usage statistics of the online platform.

In order to measure treatment fidelity of therapists face-to-face sessions are audio-taped in both treatment groups (when a patient has provided consent for this). A randomly selected sample of these session-recordings will be checked for therapist’s treatment integrity by independent raters. In the bCBT condition the raters also include a random selection of the written feedback therapists have provided on the online sessions. The sessions recordings also provide insight in the extent to which patients complied with making their homework exercises.

Time investment will be discussed in more detail in qualitative interviews for which we will invite a random selection of 10 patients per treatment group after week 30. The interviews focus on the feasibility and usability of the CBT treatment provided.