Friday, December 12, 2014

Evidence based medicine and cultural competence in medicine: is there a conflict

Skittles the ferret. She has little to do with today's post but she is absolutely stunning.

Evidence based medicine and cultural competence in medicine are two key concepts most veterinary and medical curricula are trying to accommodate simultaneously. However, there seems to be a fundamental conflict between the two. I finally understood it when I read an editorial in Health Services Research by Romana Hasnain-Wynia, shared by Dr Martin Whiting.

First though, what does each mean on its own?

Evidence-based medicine (EBM to those who know it well) is the “conscientious, explicit and judicious use of current best evidence, primarily from clinical trials, in making decisions about the care of individual patients” (Hasnain-Wynia, 2006).

Skittles looks like she has a Batman mask.
EBM is associated with diagnostic and treatment guidelines, algorithms and protocols. The aim is to standardise patient care. Overall that seems to be a good thing. It means treatment decisions aren’t based on the whims or limitations of one practitioner.

There are a few limitations of this approach. The gold standard of evidence is the randomised controlled trial, but they can be an ethical minefield. For example, subjecting a patient with a particular condition to sham surgery to compare to those receiving a surgical treatment may have an unacceptable welfare cost. So some trials just don’t happen.

ferret walks on lead
Skittles walks on a lead.
EBM is only as strong as its evidence-base, the size of which can be variable. Veterinary trials are relatively thin on the ground, and when they do exist they usually consist of small numbers of animals (with the exception of some large scale, multi-centre studies). Sometimes all we have to go by is a case series or, gulp, a case report. Or extrapolation from first principles. Or asking an expert.

And there are some treatments for which observational studies are convincing enough. Smith (2003) makes this point rather colourfully in a paper suggesting that “the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute” (see the article here).

And again. So its hard to focus on a moving ferret.
Cultural competence in medicine (CCM) is “the delivery of health services that acknowledges and understands cultural diversity in the clinical setting and respects individuals’ health beliefs, values and behaviours” (Hasnain-Wynia, 2006).

It emphasises finding out what is important to the patient. The emphasis is on individualisation, rather than standardisation, of care.

Of course it can be misused, leading to cultural stereotyping, which can be harmful to individual patients and populations. The emphasis of CCM has shifted from providing specific knowledge about certain cultural groups and minorities to promoting humility, communication, understanding patient narrative and so on.

The problem is that EBM and CCM both base recommendations on modal information from studies populations or subgroups – so critics might argue that their recommendations either don’t apply broadly enough or marginalise some individuals. The classic criticism if EBM is that it promotes “cookbook” medicine, a one-size-fits-all approach. The classic criticism of CCM is that, at its worst, is promotes cultural stereotyping.

The real questions are these: can EBM provide patient-centered care? Can CCM demonstrate improved clinical outcomes? And if they do, how can we tell? It can be challenging measuring outcomes for either model (that doesn't mean we shouldn't try).

ferret close up
Skittles held.
Hasnain-Wynia argues that despite the evolution of EBM and CCM, we need to admit that EBM does promote standardisation of care which leads to reduced discretion for clinicians and patients. On the other hand, CCM promotes discretion for clinicians and patients and may leader to greater variability in clinical care. And that is okay. There is a need for both.

Whilst these are exactly the issues that critics target, neither is inherently bad, and neither justifies canning the whole theory (or as philosophers love to say, throwing out the baby with the bathwater).

Hasnain-Wynia (2006) Is evidence-based medicine patient-centered and is patient-centered care evidence-based? Health Services Research 41(1): DOI 10.1111/j.1475-6773.2006.00504.x

Smith G (2003) Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials. BMJ 2003;327:1459