Allied Health Research
It has been an exciting decade to be involved in the emerging field of evidence-based practice for allied health. When I review my teaching notes from the past 10 years I realise how consistently and subtly evidence thinking has changed in allied health and how far forward allied health has moved in its understanding of how evidence informs practice. Ten years ago we were teaching new information for allied health practitioners about the hierarchy of evidence, which probably came to many therapists’ attention in the Lloyd-Smith paper in 1997.1 Critical appraisal of study methodology became a lot easier to teach to allied health practitioners with the arrival of PEDro and the de Vet et al approach.2,3 In particular De Vet et al (1997) promoted the need to evaluate all elements of intervention and multiple outcome measures, when critically appraising the methodological quality of an allied health research paper. This set allied health experimental research apart from many other medical experiments, and highlighted that rarely are the therapies able to have intervention arms taking a ‘blue pill’ or ‘white pill’ approach, as is so often seen in drug studies.
Therapy interventions are often a subtle combination of art and science which needs to be fully described so that others can replicate it. Moreover the outcome of an intervention generally requires multiple measures of effectiveness in order to understand the full effects of a treatment on an individual. The value of different types of primary research has also been recognised in specific allied health settings, such as N=1 studies for neurological conditions, epidemiological studies to establish cause and effect, or to explore risk factors, case studies to provide detailed information on interventions and outcomes, and qualitative research to explore how patients feel about, or respond to, treatment. Allied health clinicians now appear to be comfortable with rejecting the findings of a poorly conducted experimental study in favour of findings from a well conducted N=1 study, or a well-reported case study, when informing their treatment choices, because they have been empowered to take into account the relevance of the research to the clinical context.
The past decade has seen an increasing sophistication in allied health evidence synthesis, which explores whether there is evidence of effectiveness for an intervention when combining the findings of many individual research reports. This secondary evidence movement has probably directly contributed to a significant improvement in the way allied health research has been conducted and reported. This is regularly seen now in primary research studies with appropriate sample size power, study designs relevant to study questions, longer term follow-up, better application of inclusion/ exclusion criteria, better understanding of confounders, better defined and more clinically relevant interventions, and the use of comparison treatment arms in which subjects are offered treatments with known effects.
Reporting has certainly improved, with more appropriate statistical analysis being undertaken, and reported in a user-friendly fashion, consistent reporting of useful measures of variability occurring (such as standard deviations or confidence intervals), and information being provided on effect size and / or number needed to treat. The improved quality of allied health research is also reflected by the increasing number of allied health journals being listed on Medline and attracting impact factor ratings. The emerging strong allied health evidence base will have an increasing impact on health care world-wide. There are consistent reminders about our aging population, and what this means in terms of health care and health costs.4,5
There is congruent evidence that allied health interventions improve patient health and wellbeing, and that allied health services are cost-efficient in maintaining the independence of elderly people living in the community. With the past decade of experience in understanding what evidence has to offer allied health clinical practice, evidence-based allied health care is becoming the norm rather than the exception. Journals such as the Internet Journal of Allied Health Sciences and Practice play a vital role in efficiently bringing evidence to the attention of allied health clinicians, to assist them in evaluating and improving their practices, and to improve the lives of their patients.
- Lloyd-Smith W (1997): Evidence-based practice and occupational therapy. The British Journal of Occupational Therapy 60(11): 474-478.
- de Vet HCW, de Bie RA, van der Heijden GJM, Verhagen AP, Sijpkes P & Knipschild PG (1997): Systematic reviews on the basis of methodological criteria Physiotherapy 83 (6): 284-289.
Grimmer-Somers K. Allied Health Research. The Internet Journal of Allied Health Sciences and Practice. 2008 Apr 01;6(2), Article 3.