Lines of Evidence that Provide Empirical Support for the Person-Centred/Experiential Approach the Therapy

Entry for 13 January 2007:

The following is taken from a statement I have been working on with Jef Cornelius Young, Elke Lambers, Michael Behr, Karl-Otto Hentze and Juergen Kriz for a statement going to the German government body responsible for deciding which psychological treatments should be reimbursed by health insurance. In it I have tried to follow the inspiration of Cook & Campbell (1979), and Lakoff and Johnson (1999) in organizing the results within a framework of converging operations or triangulation of evidence:

A large empirical literature on the effectiveness of psychotherapy research, including studies published in German, clearly and strongly supports the use of PCE psychotherapies for a broad range of client problems. This literature includes data from five complementary lines of evidence:

1. Randomized comparative clinical trials and comparative outcome studies (Elliott, Greenberg & Lietaer, 2004; King et al., 2000; Stiles, Barkham, Twigg, Mellor-Clarke & Cooper, 2006; Bruce & Levant, 1990; Cornelius-White, 2007)
2. Controlled studies (against untreated controls; Elliott, 2002; Elliott et al., 2004; Bratton, Ray, Rhine, & Jones, 2005)
3. Naturalistic open clinical trials (Elliott, 2002; Elliott et al., 2004),
4. Predictive process-outcome research (Orlinsky, Rønnestad & Willutzki, 2004; Bohart, Elliott, Greenberg & Watson, 2002; Cornelius-White, 2007)
5. Patient preference research (King et al. 2000).

Each of these five lines of evidence has its own methodological strengths and limitations, but together they provide stronger evidence than any single line of research. For example, it is long-established scientific fact that randomized comparative clinical trial studies are subject to to strong researcher allegiance effects that compromise their conclusions, both generally in mental health treatment research literature (Robinson, Berman & Neimeyer, 1990; Luborsky et al., 1999; Herres et al., 2006) and specifically in the literature on PCEPs (Elliott et al., 2004). On their own, such studies therefore do not constitute a safe basis for deciding health care policy, and must be supported through the use of triangulating evidence.

References

Bohart, A.C., Elliott, R., Greenberg, L.S., Watson, J.C. (2002). Empathy. In J. Norcross, Psychotherapy relationships that work (pp. 89-108). New York: Oxford University Press.

Bohart, A.C., Elliott, R., Greenberg, L.S., Watson, J.C. (2002). Empathy. In J. Norcross, Psychotherapy relationships that work (pp. 89-108). New York: Oxford University Press.

Bratton, S. C., Ray, D. Rhine, T., Jones, L. (2005). The efficacy of play therapy with children: A meta-analytic review of treatment outcomes. Professional Psychology: Research and Practice, 36, 376-390.

Bruce, C., & Levant, R. F. (1990). A meta-analysis of parent effectiveness training. American Journal of Family Therapy, 18, 373- 384.

Cornelius-White, J. H. D. (2007). Learner-Centered Teacher-Student Relationships Are Effective: A Meta-Analysis. Review of Educational Research, 77, 1-31.

Elliott, R. (2002). The effectiveness of humanistic psychotherpies: A meta-analysis. In Cain & Seeman (Eds.) Humanistic psychotherapies: Handbook of research and practice. Washington, DC: American Psychological Association.

Elliott, R., Greenberg, L. S., & Lietaer, G. (2004). In M. J. Lambert (Ed.) Bergin and Garfield’s Handbook of Psychotherapy and Behavior Change (Fifth Edition). New York: John Wiley & Sons.

Heres, S., Davis, J., Maino, K., Jetzinger, E. Kissling, W., & Leucht, S. (2006). Why Olanzapine Beats Risperidone, Risperidone Beats Quetiapine, and Quetiapine Beats Olanzapine: An Exploratory Analysis of Head-to-Head Comparison Studies of Second-Generation Antipsychotics. American Journal of Psychiatry, 163: 185-194.

King, M., Sibbald, B., Ward, E., Bower, P., Lloyd, M., Gabbay, M., & Byford, S. (2000). Randomised controlled trial of non-directive counselling, cognitive-behavior therapy and usual general practitioner care in the management of depression as well as mixed anxiety and depression in primary care [Monograph]. Health Technology Assessment, 4 (19), 1-84.

Luborsky, L., Diguer, L., Seligman, D.A., Rosenthal, R., Krause, E.D., Johnson, S., Halperin, G., Bishop, M., Berman, J.S., & Schweizer, E. (1999). The researcher’s own therapy allegiances: A “wild card” in comparisons of treatment efficacy. Clinical Psychology,: Science and Practice, 6, 95- 106.

Orlinsky, D.E., Rønnestad, M.H., & Willutzki, U. (2004). Process and Outcome in Psychotherapy. In M.J. Lambert (Ed.), Bergin and Garfield’s Handbook of Psychotherapy and Behavior Change (5th Ed; pp. 307-389). New York: Wiley.