Evidence Based or Evidence Biased? Two views of science in clinical psychology and psychotherapy

This comment was originally posted as a “Reader Response” on the publication date indicated above. All Reader Responses are now available as comments. Two cultures (scientific and clinical) speaking different theoretical languages reside in psychology. … Unfortunately, both cultures use the same sensory-system–based vocabulary, which leads to the unwitting and confusing assumption that they are speaking the same language (Zoltan Gross, 2001)(1). At the beginning the RCTs (randomized controlled trials) approach obtained a strong consensus of approval among researchers in clinical psychology and psychotherapy. Subsequently many researchers have moved from a starting period of unconditional faith in the experimental method to a position of partial scepticism: paradoxically the more rigorous and provable the research is, following the criteria of ‘the classic scientific method’, the less it becomes valid significant and classifiable from the point of view of day-to-day practice (2). The researcher, like the clinician, faces the dilemma of whether it is best to sacrifice the quest for full knowledge to the thoroughness of the research method or vice versa (3). Westen et al. emphasise how certain assumptions implicit to the method of experimentation can conspire to transform the perception of the clinical picture once it becomes evaluated (4). How the scientific method is selected involves language choices (linguistic or conceptual) within which the intellectual problem is couched, so that we can say that if the choice of language speaks to the problem, so also the presenting problem is expressed in the same language. The method chosen contributes toward establishing the nature of the problem to which it is applied. According to Deegear et al., “Although there are political, societal and monetary enticements to accepting the current rendering of ESTs sufficient evidence has cast doubt on the movement as it currently exists” (p. 276, 5) (ESTs are the Empirically Supported Treatments, id est EBM in psychotherapy). Moreover the term “evidence” itself does not have one single definition but it is depending on the various contexts where it is used (6). This contribution has not tried to discredit the Evidence Based approach but rather to throw light on the limits of such a framework and to underline the Vandenbroucke’s valiant conciliatory effort to establish different hierarchies for different problems. Therefore if it is true that the ESTs focus on the experimental effectiveness of psychotherapy represents an important step forward, it is also true that only a similar focus on clinical efficacy can increase trust about psychotherapy in the public. Perhaps, as underlined by Joyce et al., the practice of psychotherapy concerns “art” and “craft”: “Should the practice of psychotherapy be regarded primarily as an art or as a craft? Alternatively, does it display characteristics of a scientific discipline? … This uniqueness is not often captured by the scientific method, and thus, it can be regarded as a form of artistry” (p. 798, 7). 1. Gross, Z. (2001). Two Languages, One Vocabulary. J of Psych Integr, 11(4), 481-505. 2. Di Nuovo, S., & Lo Verso, G. (2005). Come funzionano le psicoterapie, Angeli, Milano 3. Salvini, A. (1998). Argomenti di Psicologia Clinica, Upsel 4. Westen, D., Novotny, C., & Thompson-Brenner, H. (2004). The empirical status of empirically supported therapies: Assumptions, methods, and findings, Psych Bull, 130, 631-663. 5. Deegear, J., & Lawson, D. M. (2003). The Utility of Empirical Supported Treatments. Prof Psych: Res and Prac, 54(3), 271-277. 6. Upshur, R. E. G., VanDenKerkhof, E. G., & Goel, V. (2001). Meaning and measurement: an inclusive model of evidence in health care. J of Eval in Clin Pract, 7(2), 91-96. 7. Joyce, A. S., Wolfaardt, U., Sribney, C., & Aylwin, A. S. (2006). Psychotherapy research at the start of the 21st century: art versus science controversy. Can J Psychiatry, 51(13), 797-809.