The assessment of adherence represents a central quality criterion in therapy-outcome studies. The importance of judging this quality criterion on the part of external raters is mentioned repeatedly across various studies on the grounds of the replicability and the comparability of the therapy methods applied (Kendall, Holmbeck & Verduin, 2004). Furthermore, other authors emphasise adherence as a central component of methodological aspects, such as the construct and the internal validity (Leichsenring, Salzer, Hilsenroth, Leibing, Leweke & Rabung, 2011; Shadish & Cook, 2009; Shadish, Cook & Campbell, 2002). Not infrequently, the objective measurement of adherence by raters using rating scales is contextually based on the manuals applied in the studies. Thus, both effectiveness studies (naturalistic designs) as well as investigations of long-term treatments (e.g. analytical psychotherapy over 300 sessions) represent a special challenge in the measurement of the adherence: These are therapies in which manualised approaches are not usual and in which other means have to be utilised when developing an adherence measurement instrument. And the intention is to take exactly such a route in this project.
To date it has been shown that, despite a wide range of research efforts in the Anglo-American language areas especially, the separation between different forms of psychodynamic methods represents a particular difficulty (Caligor et al., 2012). Likewise in the German language area, with its division of the methods approved in the applicable guidelines into "depth psychology-based therapy" and "analytical therapy" (DPT and AT), an adherence measurement instrument faces the special requirement of discriminating validly between these two methods.
With the help of a multi-step approach, an adherence measurement instrument should be constructed capable of a valid separation especially between these two psychologically-based methods (DPT and AT). The unique aspect of the construction process lies in the fact that this should occur on the basis of real treatments conducted, taken from the Munich Psychotherapy Study (MPS; Huber, Henrich, Clarkin & Klug, 2013; Huber, Zimmermann, Henrich & Klug, 2012). The individual steps are as follows:
1. Systematic literature research for the development of items with content typical for the DPT and AT methods (already occurred).
2. Group discussions with N=6 male/female experts (training analysts) about the items developed specifically and a consensual assessment of the items with respect to their ability to discriminate in relation to DPT and AT (already occurred).
3. Assessment of the adherence to the methods: In order to be able to apply the developed items to really conducted therapy sessions, which are regarded as prototypical for the respective methods comparatively speaking, such therapy sessions are to be analysed as follows: Sound-recorded DTP and AT therapy sessions from the mid phase of the therapy are each assessed by N=2 external independent raters (training analysts and learning therapists) with respect to the adherence to the methods. Only those therapy sessions in which the two raters are in agreement with the therapy method detailed by the MPS (Munich Psychotherapy Study), therapists providing the treatment form the data basis for step 4 (already occurred).
4. Application of the items (from step 2) to the sound-recorded DTP and AT expert therapy sessions (from step 3): Psychotherapists who practice analysis and depth psychology (with at least five years of professional experience) assess to what extent the contents of the items are actually achieved in the really conducted AT and DTP treatments (already occurred).
5. Revision of the items pool on the basis of the ratings from step 4.
6. Recruitment of a further group of raters (postgraduate psychologists) who should be trained in optimising the reliability of the scale.
A reliable and discrimination-capable adherence measurement instrument is regarded as an important step in comparative psychotherapy research: It would secure the construct validity especially with naturalistic studies and contribute to the empirical clarification of the differential effectiveness of long-term psychotherapies.
Dipl.-Psych. Melanie Ratzek
International Psychoanalytic University Berlin
Research methods, theory of science and psychological diagnostics
Stromstr. 3b, 10555 Berlin
Fon 030-330 117 767
Fax 030-300 117-769
Dr. Günther Klug
Klinik und Poliklinik für Psychosomatische Medizin und Psychotherapie/Clinic and Polyclinic for Psychosomatic Medicine and Psychotherapy
TU Munich University
Langerstr. 3, 81675 Munich
Fon 089-649 105 44
Prof. Dr. Dr. Dorothea Huber
International Psychanalytic University
Stromstraße 3b, 10555 Berlin