CORRESPONDENCE

RESPONSE: Re: Systematic Review of Psychological Therapies for Cancer Patients: Overview and Recommendations for Future Research

Sallie Anne Newell, Rob William Sanson-Fisher, Nina Johanna Savolainen

Affiliations of authors: NSW Cancer Council Cancer Education Research Program, Newcastle, New South Wales, Australia; Faculty of Medicine and Health Sciences, University of Newcastle, Newcastle; Health Promotion Unit, Northern Rivers Area Health Service, Lismore, New South Wales; Southern Cross University, Lismore. NSW Cancer Council Cancer Education Research Program, Newcastle; Faculty of Medicine and Health Sciences, University of Newcastle, Newcastle. NSW Cancer Council Cancer Education Research Program, Newcastle; Commonwealth Grants Commission, Canberra, Australian Capital Territory, Australia.

Correspondence to: The Secretary, New South Wales Cancer Council Cancer Education Research Program, Locked Bag 10, Wallsend, NSW, 2287 (e-mail: sallien{at}nrhs.health.nsw.gov.au).

Brédart et al. raise numerous concerns about the conduct and conclusions of our review (1). First, they are concerned that clinicians and administrators will conclude that psychological therapies are worthless and thus reduce their attempts to address patients‘ psychological needs. We acknowledge that cancer patients have high levels of psychological needs and share the disappointment of Brédart and her colleagues that we could not produce stronger recommendations (2). However, to draw such a conclusion would be a gross misinterpretation of our findings—we did make tentative recommendations about the potential benefits of various psychological therapies but could not currently endorse their widespread implementation.

Second, they suggested that we could not perform meta-analyses because we combined groups of therapies that were too diverse. The opposite is actually true—we felt it inappropriate to combine such varied interventions (and outcomes), and therefore we reviewed results separately for 18 psychological therapies in relation to 19 outcomes.

Third, they suggested that we had ignored three previous meta-analyses that reported positive results (3–5). The first of these was published after our literature search ended and excluded many relevant trials because of missing data—one of the reasons we decided against using meta-analyses (3). It also explored only two outcomes and concluded that psychological therapies may help one but not the other (3). The second meta-analysis (4), which was not specifically concerned with cancer patients, concluded that " ...limitations in outcome studies and meta-analytic reviews currently prevent us from drawing strong generalized inferences..." and noted that "There is mounting evidence suggesting that biases associated with individual studies do not cancel each other out when studies are combined meta-analytically, leading to inflated mean effect estimates for some interventions ... and deflated estimates for others." We discussed the third meta-analysis (5), which, although well conducted, used more diverse therapy and outcome combinations and included less than half as many trials as did our review. When the therapies were subdivided, less than half of the effect sizes reached statistical significance and half of those only just reached it (5). Therefore, we do not believe that the results of these meta-analyses contradict the conclusions of our review.

Fourth, Brédart et al. (2) were concerned about our focus on randomized controlled trials (RCTs) and suggested that qualitative methods may be a more appropriate way of testing therapies. Although we acknowledge that qualitative research may contribute much to developing hypotheses of therapies that may assist cancer patients, we believe there is widespread acceptance in the scientific community that well-conducted RCTs are, wherever feasible, the preferred methodology for testing the efficacy of such therapies.

Fifth, they felt that our methodologic quality criteria were inappropriate for trials that evaluated psychological therapies. Our review dedicated considerable space to justifying the criteria used and concluding that only the care provider blinding criteria would be impossible, and then only for therapist-delivered interventions. However, we also discussed how this potential bias could be minimized by ensuring equivalency of other treatments, monitoring care providers‘ adherence to protocols, and avoiding care provider-rated outcomes. Because most evaluations of psychological therapies employ patient-rated outcomes, we have had minimal difficulties convincing ethics committees of the frequent need to temporarily conceal the true nature of such trials from participants until after final evaluations. Without such blinding, social desirability bias would make any statistically significant results very difficult to accept with confidence.

Sixth, they disagree that the methodologic rigor of RCTs of psychological therapies can be improved without substantially increasing costs. As discussed in our review, we disagree, but even if it were true, we remain unconvinced that it would justify conducting poor-quality trials.

Finally, Brédart et al. (2) say that we should acknowledge, highlight, and encourage the efforts made by the psycho-oncology community to assess its practice and to introduce rigorous methods. The early part of our review does acknowledge efforts toward greater use of RCTs but found their methodologic quality had improved little over time—hence the section trying to encourage such improvements.

References

1 Newell SA, Sanson-Fisher RW, Savolainen NJ. Systematic review of psychological therapies for cancer patients: overview and recommendations for future research. J Natl Cancer Inst 2002;94:558–84.[Abstract/Free Full Text]

2 Newell S, Sanson-Fisher RW, Girgis A, Ackland S. The physical and psycho-social experiences of patients attending an outpatient medical oncology department: a cross-sectional study. Eur J Cancer Care (Engl) 1999;8:73–82.

3 Sheard T, Maguire P. The effect of psychological interventions on anxiety and depression in cancer patients: results of two meta-analyses. Br J Cancer 1999;80:1770–80.[Medline]

4 Matt GE, Navarro AM. What meta-analyses have and have not taught us about psychotherapy effects: a review and future directions. Clin Psychol Rev 1997;17:1–32.[Medline]

5 Meyer TJ, Mark MM. Effects of psychosocial interventions with adult cancer patients: a meta-analysis of randomized experiments. Health Psychol 1995;14:101–8.[Medline]



             
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