Evidence in palliative care research: how should it be gathered?

Aoun, Samar M; Kristjanson, Linda J

doi:10.5694/j.1326-5377.2005.tb07034.x

Topics

Statistics, epidemiology and research design

Randomised controlled trials are often not feasible or not appropriate in palliative care research

In evaluating evidence for clinical care, study designs are graded according to their potential to eliminate bias,1 and the most robust evidence is considered to come from randomised controlled trials (RCTs).2,3 However, the reliance on study design as the main criterion for credibility of evidence has its critics,4 as does this view of what constitutes the “best” evidence.5,6 In public health in particular, there is debate about the primacy of the RCT for evaluating interventions and about the tendency to downgrade the contribution of observational studies.7,8

School of Nursing, Midwifery and Postgraduate Medicine, Edith Cowan University, Perth, WA.

Correspondence:

Acknowledgements:

Linda Kristjanson gratefully acknowledges the support of the Cancer Council of Western Australia, which funds her chair of Palliative Care.

Competing interests:

None identified.

1. National Health and Medical Research Council. NHMRC standards and procedures for externally developed clinical practice guidelines. Canberra: NHMRC, 2005. Available at: http://www.nhmrc.gov.au/publications/synopses/nh56syn.htm (accessed Aug 2005).
2. Sackett D, Rosenberg W, Gray J, et al. Evidence based medicine: what it is and what it isn’t. BMJ 1996; 312: 71-72.
3. Haynes RB, Devereaux PJ, Guyatt GH. Physicians’ and patients’ choices in evidence based practice. BMJ 2002; 324: 1350.
4. Rychetnik L, Frommer M, Hawe P, Shiell A. Criteria for evaluating evidence on public health interventions. J Epidemiol Community Health 2002; 56: 119-127.
5. Williams D, Garner J. The case against “the evidence": a different perspective on evidence-based medicine. Br J Psychiatry 2002; 180: 8-12.
6. Concato J, Shah N, Horwitz N. Randomized, controlled trials, observational studies, and the hierarchy of research designs. N Engl J Med 2000; 342: 1887-1892.
7. Ioannidis JP, Haidich AB, Lau J. Any casualties in the clash of randomised and observational evidence? BMJ 2001; 322: 879-880.
8. Deeks JJ, D’Amico R, Sakarovitch C, Altman DG. How big are the biases associated with non-randomised designs used in evaluations of healthcare interventions? An empirical investigation [abstract]. Oral presentation at the 3rd Symposium on Systematic Reviews: beyond the basics. Improving quality and impact; 2000 Jul 3-5; Oxford, UK. Available at: http://www.ihs.ox.ac.uk/csm/Oralabstract2K.htm#Deeks1 (accessed Jun 2005).
9. Bennett M, Ahmedzai M; APM Science Committee Association for Palliative Medicine. Evidence-based clinical guidelines for palliative care: the work of the APM Science Committee. Palliat Med 2000; 14: 453-454.
10. Hudson P, Aranda S, McMurray N. Randomized controlled trials in palliative care: overcoming the obstacles. Int J Palliat Nurs 2001; 7: 427-434.
11. King M. The effects of patients’ and practitioners’ preferences on randomized clinical trials. Palliat Med 2000; 14: 539-542.
12. Harding R, Higginson R. What is the best way to help caregivers in cancer and palliative care? A systematic literature review of interventions and their effectiveness. Palliat Med 2003; 17: 63-74.
13. Grande GE, Todd CJ. Why are trials in palliative care so difficult? Palliat Med 2000; 14: 69-74.
14. Aldrich R, Kemp L, Williams L, et al. Using socioeconomic evidence in clinical practice guidelines. BMJ 2003; 327: 1283-1285.
15. National Health and Medical Research Council. A guide to the development, implementation and evaluation of clinical practice guidelines. Canberra: NHMRC, 1999.
16. Keeley D. Rigorous assessment of palliative care revisited. Wisdom and compassion are needed when evidence is lacking. BMJ 1999; 319: 1447-1448.
17. Grande GE, Todd CJ, Barclay SI, Farquhar M. Does hospital at home for palliative care facilitate death at home? Randomised controlled trial. BMJ 1999; 319: 1472-1475.
18. Australian Government Department of Health and Ageing. Guidelines for a palliative approach in residential aged care. Canberra: The Department, 2004. Available at: http://www.health.gov.au/internet/wcms/publishing.nsf/Content/palliativecare-pubs-workf-guide.htm/$FILE/guideall.pdf (accessed Jun 2005).
19. National Health and Medical Research Council. How to use the evidence: assessment and application of scientific evidence. Canberra: NHMRC, 2000.
20. Raphael D. The question of evidence in health promotion. Health Promot Int 2000; 15: 355-367.
21. Tammemagi C, Neslund-Dudas C, Simoff M, Kvale P. In lung cancer patients, age, race-ethnicity, gender and smoking predict adverse comorbidity, which in turn predicts treatment and survival. J Clin Epidemiol 2004; 57: 597-609.
22. Kemp L, Harris E, Aldrich R, et al. Randomised controlled trials and equity-based evidence. In: Ritchie J, editor. Made in the future. Proceedings of the 14th Annual Conference of the Australian Health Promotion Association; 2002 Jun 16-19; Sydney. Maroochydore, Qld: The Association.
23. Jackson K, Ashby M, Martin P, et al. “Burst” ketamine for refractory cancer pain: an open label audit of 39 patients. J Pain Symptom Manage 2001; 22: 834-842.
24. Jackson K, Ashby M, Goodchild C. Subanesthetic ketamine for cancer pain: by insisting on level I/II evidence, do we risk throwing the baby out with the bath water? J Pain Symptom Manage 2005; 29: 328-330.
25. Lynn J, Nolan K, Kabcenell A, et al. Reforming care for persons near the end of life: the promise of quality improvement. Ann Intern Med 2002; 137: 117-122.
26. Abernethy A, Currow D, Frith P, et al. Randomised, double blind, placebo controlled crossover trial of sustained release morphine for the management of refractory dyspnoea. BMJ 2003; 327: 523-528.

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