Limitations
anxiety, vertigo
PATHOLOGY, RECRUITMENT, DISORDERS
There are some limitations we should acknowledge in this study. The first limitation regards the generalizability of our results. The sample was not very large, the recruitment number was not based on a sample size estimate, and the sample came from just one medical center. Moreover, the sample chosen was not an arbitrary choice, although neither was it an actual randomization. The second limitation concerns the absence of data on patient personality characteristics or other features that may have allowed us to obtain a more homogeneous sample (e.g., no preliminary assessments were made on the presence of any personality disorders that could aggravate the pathology in progress). The third limitation was that it was not possible to determine if the control group had any change in psycho-physiological parameters (only monitored in the biofeedback group), because these parameters were not measured for the controls. Finally, a further limitation of this study is that the mechanism through which biofeedback allowed a resolution of the vertigo symptoms is not currently known. In addition, several biofeedback protocols (EMG, HRV, and respiratory) were used, and it is unknown which protocol contributed most to the outcome. A reduction in the patient’s sympathetic activation and a reduction in anxiety can be hypothesized. However, further studies are needed to investigate the mechanism by which biofeedback works.