Why Carry Out A Randomised Control Trial?

At Seating Matters we frequently make reference to our clinical research project, carried out by Ulster University. 

This blog is to describe how a RCT can differ from other forms of research to help you discern the difference when making clinical decisions on behalf of your patients.



Everyday, clinicians are making decisions on seating provision for their patients.  As an Occupational Therapist providing equipment for patients, I felt that the existing testing, studies or trials that had been carried out on other equipment did not give me sufficient information and therefore confidence to make a valid, clinical decision which would ensure a positive clinical outcome for my patients.

I felt strongly that it was essential to carry out independent, ethical and robust research into a product in order to aid the decision making process of my fellow clinicians when it came to the Seating Matters chairs.

Please click here to read my blog on “What is good research?”. 

To this end, I worked with Ulster University to see if they could design a large-scale randomised control trial to establish the effectiveness of the Seating Matters chairs with a group of real patients in active care settings.

Professor Suzanne Martin, Jackie Casey OT and Orlagh Daly OT led this research with support from Olivia Tierney OT and myself, Martina Tierney.

This research collated quantitative and qualitative data which allowed us to gather accurate, measurable results but also to receive feedback from patients and caregivers.  This trial was ethically approved by both the University’s ethics department and the Office of Research Ethics Committee.

The 40 participants in this trial were recruited from 3 nursing homes and randomly allocated to one of two groups – control and intervention – by Ulster University researchers.  These participants were monitored multiple times per week, for 12 weeks, allowing us to analyse and monitor patient changes and developments in patients’ seating and postural abilities, reduction in pressure injuries, oxygen levels, functional skills and caregiver input.

The study design ensured that this project was robust, impartial and would give sound results that could be relied upon to aid clinical decision making.


This hierarchy of evidence demonstrates how different forms of research should be treated in relation to the quality of evidence and the risk of bias. The Seating Matters / Ulster University research project is in the top tier of the hierarchy. 



Many products are not supported by any type of clinical research whatsoever.  Other equipment may have a brochure or marketing material that quotes “research” of different types.

It’s important that you understand the difference in the types of research and discern which may be relied upon to influence your clinical decisions.

Product Trial:

This entails a group of people providing their opinions on a product by examining, using or testing that product.

A product trial is often done informally with a group of volunteers, industry professionals or other participants over a short period of time.  In some cases, product trials are paid for by manufacturers and therefore lack independent oversight and can be open to bias.

Product trials can be useful in gauging opinions or for doing analysis of the reception of a product in a certain environment. However, they may not be an accurate representation of those who would be clinically advised to use the product tested in this type of trial.

Even the involvement of a university or similar body does in a product trial does not guarantee robustness of the results. Without the robust study design that comes with other forms of research, a mere product trial cannot be relied upon to extrapolate findings into the recommendation of equipment as treatment for complex medical conditions.

Endorsements by Industry Professionals:

Product endorsement by Occupational Therapists, doctors or other industry personalities often is done as a marketing promotion to give a product recognition.

This can be open to bias as the person giving the endorsement is receiving a payment incentive for giving the product appreciation.  In many cases, this person will have had no input to the design, may not have independently analysed clinical data relating to the product and may not even be aware of how the products’ features could impact patient outcomes.

Lab Trial:

A lab trial would entail a product being tested in a very controlled, artificial environment, often using healthy volunteers under very specific conditions.  As a tool, it can be useful in analysing small changes in external factors impacting the volunteer.  In these cases, tools such as pressure maps can be useful in highlighting some of the effects of those changes.

One must be careful when making the leap from taking the result of a lab trial and using that to draw conclusions for how a product may then work in a real-life setting.  Let’s take the pressure map as an example.

When pressure mapping is done in these situations, an able-bodied person could be used to sit poorly on a chair and a snapshot is taken using a pressure mapping device.  If the person moves their body, even only slightly, a very different result could be given.  This result could show a much improved map of the person’s body with less red spikes and seemingly reduced pressure.

Some manufacturers would then take this improved image and use that on their marketing materials as a way to justify that their product can result in reduced pressure through parts of a patient’s body.

However, this pressure map only represents a snapshot of the pressure going through the volunteer’s body at this very specific period of time.  This cannot be used to guarantee an effect or a similar outcome for an elderly person sitting in a chair for a long period of time in a nursing home under very different circumstances.

A lab trial can be useful as a small component of a larger study and pressure mapping does have its merits in certain circumstances.

However, when you’re presented with an image of a pressure map, you must establish if this pressure map is indicative of how this product might perform with your patient.

If the pressure mapping image was taken in a lab environment or with a healthy volunteer or over a short period of time and perhaps without ethical oversight, you would be advised to not base your clinical decision on that alone.

Literature Review:

A literature review or “lit review” is an exercise that is undertaken to establish what research has been done on specific topics in the past.

In order to carry out a lit review, you must first establish the research question, search relevant databases for research on that subject and then define a set of criteria by which to weed out non-relevant research.  For example, you could decide to do a lit review based on the research carried out in Canada in the past 5 years that focused on patients over 65 years old living in long term care who had suffered from a stroke.

It can be a beneficial exercise to carry out a lit review prior to a RCT as this allows a gap in research on the relevant topic to be identified, allowing the research to directly focus on this topic area.

As a result of a comprehensive lit review, you may establish that enough research exists on the topic and you may be comfortable in drawing conclusions from that.  When research is sparse in the subject area, further research may be required.

Ulster University carried out a lit review of relevant research on the topic of specialised seating prior to conducting the RCT we refer to above.  They determined that further research was required in the subject area and so they developed the Seating Matters / UUJ Randomised Control Trial to examine the subject area in greater depth.


** This post was originally published on http://blog.seatingmatters.com/why-carry-out-a-randomised-control-trial

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