In short Article

Clinical relevance of research findings

What’s the benefit for patients?


Doctors, pharmacists and other care providers cannot always easily tell whether the findings of research into drugs and medical devices, often presented attractive and ‘glossy’ ways, will actually benefit their patients in their everyday practice. Even though the study outcomes may be based on complex statistics and analyses, patients are entitled to expect that care providers who prescribe or deliver these drugs or medical devices take a rational and critical view of them. The fact is that many publications about such studies suffer from statistical hyperbole and a lack of truly clinically relevant findings. Causes of this include the use of unsuitable or irrelevant outcome measures, the fact that large numbers of participants are needed to establish small effects, and the problem that the patients included in the study are often not representative of the kind of patients encountered in routine practice. These problems occur even in studies that are published in prestigious journals, or that are used to support a request for market authorisation. The present Ge-Bu review paper uses some examples to show how care providers can judge the clinical relevance (i.e. the benefits to patients) of research findings, without having to be ‘experienced, trained researchers’ themselves.

  • The concept of ‘significance’, which is often used in marketing based on research into drugs or medical devices, is insufficient to enable care providers to judge whether the treatment effects found in the studies will actually benefit their patients.
  • Whether statistically significant research findings are actually meaningful for patients coming to a pharmacy or seen in consultations depends on the ability to detect a treatment effect among the study participants (the ‘power’ of the study), on the ability to establish the effect size for the clinically most relevant outcome measure among the participants, and on the representativeness for the patients.
  • Sound scientific research into drugs or medical devices requires that a power calculation for the main (primary) outcome measure is made in advance, and that the researchers determine in advance what treatment effect is clinically relevant for patients seen in routine practice. 
  • When examining the outcomes of non-inferiority studies it is even more important to ask oneself what benefits they offer to patients visiting the pharmacy or seen in consultations, especially if the study only shows that a particular treatment is not inferior to an existing one.
  • Health care authorities and guideline developers have a responsibility to check whether drugs or medical devices that are to be officially authorised or to be recommended are actually based on clinically relevant outcome measures.
  • Care providers who are involved in prescribing or delivering drugs and medical devices should, as much as possible, be familiar with concepts like statistical significance versus clinically relevant treatment effects, the number-needed-to-treat, as well as with the value of the various types of outcome measures (hard, surrogate or composite). Only then can they correctly inform their patients about the (often overly optimistic) research findings.
  • Care providers should be able to see through the ‘glossy’ marketing presentations of drugs and medical devices, and should continue to concentrate on the true clinical relevance of published research findings, and to act accordingly in their direct contacts with patients.

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Authors

  • drs K. van Deventer, dr H.J.E.M. Janssens