The importance of observational studies

Our study, Observational Studies: Specific Considerations for the Physical and Rehabilitation Medicine Physicianwas recently published in the American Journal of Physical Medicine & Rehabilitation

Experimental and non-experimental designs are used to investigate the effect or association of an intervention and clinical or surrogate outcome. These methods aim to improve knowledge and develop new strategies to manage a disease or condition. 

While experimental research studies entail scrutiny by the scientist and provide results that are less prone to systematic errors, their downside is that they are poorly generalisable. “What all this means in clinical terms,” explains Dr Sabrina Donzelli, physiatrist at Isico and first author of the published research,” is that a treatment that worked fine during a study may in the long term, following its prescription by a hospital or general practitioner, throw up problems that did not emerge in the experimental research”. 

Therefore, to verify what happens in the real world, non-experimental studies, called observational studies, can be carried out, of the kind dealt with by the research we have just published. 

Well-designed observational studies can provide valuable information regarding exposure factors and the event under investigation

“Basically, what the researcher does is simply observe data, without having the possibility to manipulate it”, Dr Donzelli goes on. “The researcher’s task is to interpret and contextualise the results, taking into account all potential errors introduced during the selection of the study sample. To eliminate, as far as possible, systematic errors that could lead to incorrect evaluations and interpretations, it is necessary to implement a series of methodological strategies that are not very widespread in the rehabilitation field.” 

In physical and rehabilitation medicine, where complex procedures and multiple risk factors can be involved in the same disease, the use of observational study must be planned in detail and a priori to avoid overestimations. 

“This is why we wrote this article, to offer clear suggestions to researchers in the rehabilitation field who are interested in planning an observational study”, concludes Dr Donzelli. “We give an overview of the methods used for observational design studies and describe when it is appropriate to use them and how to do so in different scenarios”.