What is "conventional therapy"? A 10-years systematic review on physical rehabilitation in multiple sclerosis

Background. In controlled studies on physical rehabilitation, the term “conventional therapy” is generally used in referring to the nonexperimental group. It seems to indicate a unique and usual practice, commonly known and widely accepted. However, what is “conventional therapy” in practice? Our aims were to determine whether exists a univocal and homogeneous definition of this expression, to analyze its meaning and to define its specific features. To do so, we focused on the physical rehabilitation for people with multiple sclerosis (MS) and we systematically reviewed published clinical trials on this topic. Methods. A systematic literature search was conducted using MEDLINE from 2008 to 2018. Inclusion criteria were: controlled clinical trials on MS physical rehabilitation; “conventional therapy” or synonyms that are commonly used to classify the treatment program in the control group (e.g., “traditional physical therapy”, “standard rehabilitation program”, “conventional rehabilitation”); people with MS recruited both in experimental group and in control group. Results. Of 884 references identified through electronic searching, 122 were eligible for evaluation. The 84% of papers did not fulfil the inclusion criteria. One third of these did not provide a specific description for “conventional therapy” or synonyms. Thus, we totally screened 19 clinical trials. Only 2 studies specified the use of the Consolidated Standards of Reporting Trials (CONSORT) Statement guidelines. The present review enabled to highlight a situation of heterogeneity in the definition of “conventional therapy”, including a multitude of interventional strategies, with differences in volumes and intensities of therapies. A remarkable difference was also found in the number of interventions assigned as conventional rehabilitation, which ranged from 1 to 7; the 58% of studies administered at least 4 treatments. This heterogeneity was reflected in studies that took place in different countries, as well as in studies conducted within the same country, emphasizing the lack of a common line of intervention also at national level. Conclusion. To date, the umbrella term “conventional therapy” seems not to provide a univocal definition for the control treatment in MS physical rehabilitation trials. This heterogeneity in definition and specific features may lead to reduce the quality of the studies, limiting the comparability between trials and decreasing the reproducibility of the protocol. The present review focuses on the need to find new standardised, uniform and shared protocols for MS conventional rehabilitation.