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- Page navigation anchor for Effectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary careEffectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary careResponse to Arooj KharlWe appreciate the authors the statement that patients in the primary care population may be different from patients referred to an otorinolaryngologist for BPPV, as this is the fact that gives sense to our study.In response to the fact that our results focus on the subgroup of patients with positive Dix Hallpike test with nystagmus, and “the analysis of subgroups with and without nystagmus was not predefined in the published study protocol”, it has to be said that is not entirely true. Already in the published protocol1 it was noted that patients with Dix Hallpike test with nystagmus were collected separately from those who did not present it in order to analyze them separately. Thus, the results are shown globally in table 2 and separately in figures 2 and 3 of our article.Our study should be seen as a starting point in which general practitioners without experience in the management of vertigo can solve cases of BPPV, after a short workshop, if the diagnosis is reliable due to the presence of nystagmus. We think that with more clinical experience and training, the diagnostic and therapeutic efficacy could improve.The fact of excluding patients from vestibular migraine was an exercise in prudence since, according to the current literature,2 BPPV and vestibular...Show MoreCompeting Interests: None declared.
- Page navigation anchor for Effectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary care - Response to Karla HemmingEffectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary care - Response to Karla HemmingWe truly appreciate the attention paid to our study. However, we would like to provide some elements we think deserve consideration. Firstly, regarding pre-specification, we highly encourage to check the trial registration (ClinicalTrials.gov, Identifier:NCT01969513) which is referenced in our published study protocol. We cannot but agree with Dr Hemming in the fact that neither the discussed paper nor the protocol publication described the hierarchy of the outcomes, despite of being correctly defined in the trial registration. Secondary outcomes defined in the trial registration but not included in the discussed paper -due to their different nature (quality of life and betahistine use) are being addressed in different papers still to be published.We decided to homogeneously analyze our similar longitudinal outcomes with similar multivariate mixed models, despite of the hypothesized relevant follow-up defined in the trial registration. These analyses led to conclusions we consider are based enough and address our objectives. Keeping in mind the limitations of the paper - including multiple comparisons, we honestly believe that it adds evidence and guidance to this line of research, being worth the effort of the research team, funding agency and patients.We are really sorry if our paper lacked in providing such relevant information that could help to contextualize the relevance of our study, we tried or...Show MoreCompeting Interests: None declared.
- Page navigation anchor for Effectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary careEffectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary careThe study by Moreno and colleagues investigates the effectiveness of the Epley maneuver in posterior canal benign paroxysmal positional vertigo (BPPV) in primary care – a highly relevant research question, as patients in the primary care population may be different from patients referred to an otorinolaryngologist for BPPV. However, the conclusion of the article does not fully answer the main research question of the article; instead, it only focuses on the significant results concerning the subgroup with a positive Dix Hallpike test with nystagmus (i.e. those with objective BPPV). However, results of the complete groups (including both patients with objective and subjective BPPV) are neither presented in the abstract nor in the results section, although the authors claim to have performed analyses according to the intention-to-treat principle. Furthermore, the analysis of subgroups with and without nystagmus was not predefined in the published study protocol. Caution should be exercised when reporting subgroup estimates, as they may be spurious.1In light of this analysis principle, the 19 patients with vestibular migraine which were excluded after randomization had already taken place, should ideally have been analyzed with their original groups; instead, the flowchart of participants incorrectly reports these patients had already been excluded before randomization....Show MoreCompeting Interests: None declared.
- Page navigation anchor for Bow and rise test leaves time for Epley in a 10 minute consultation - Response to Andrew AshworthBow and rise test leaves time for Epley in a 10 minute consultation - Response to Andrew AshworthWe appreciate your contribution. It would be interesting to know which is the negative predictive value in this exploration for the negative response in Dix Hallpike’s test, since in case of being elevated it would allow to save some exploration. We would greatly thank the author if he could provide us any bibliographic reference in that sense. According to our experience with the Dix Hallpike’s test, performed in those patients with compatible clinical symptoms with Benign Paroxysmal Positional Vertigo, the test is useful, tolerated, and done in not more than two minutes. Furthermore, in case the results are positive, it is very easy to continue with the Epley maneuver. Besides, the difficulty to interpret the presence or absence of nystagmus is one more argument to do the complete Dix Hallpike test, as our study shows. We must wait for the latency period and observe very carefully in order to visualize the nystagmus less evident to the naked eye. It is in these cases where the Epley maneuver will work clearly.Competing Interests: None declared.
- Page navigation anchor for Bow and rise test leaves time for Epley in a 10 minute consultationBow and rise test leaves time for Epley in a 10 minute consultation
Getting every vertiginous patient onto a couch to go through the discomfort of a Dix-Hallpike test is time consuming, especially where an Epley manoeuvre is not then indicated.
In my own practice I have developed and use what I term a "bow and rise" test based on the anatomical positions of the posterior semicircular canals (PSSC) which are those most affected by a build up of otoliths and lie at approximately 45 degrees to the midline.
The seated patient is invited to look 45 degrees to one side (thus bringing the PSSC under test into a sagittal plane and neutralising the other in a coronal plane). The patient is invited to bow so that the head is parallel to the floor and then rise back to a seated position quickly. If the patient becomes dizzy (asking is sufficient) on one side and not the other, I carry out an Epley manoeuvre on that side.
In my experience, presentation of symptoms, positive bow and rise and Epley manoeuvre are easily performed within a 10 minute consultation with this simple application of basic anatomy.
Competing Interests: None declared. - Page navigation anchor for Effectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary careEffectiveness of the Epley manoeuvre in posterior canal benign paroxysmal positional vertigo: a randomised clinical trial in primary care
Moreno and colleagues report that the Epley manoeuvre is an effective treatment for posterior canal benign paroxysmal positional vertigo. However, the study has several fundamental methodological shortcomings, which cast doubt on this finding. This study should not be used as evidence in support of the procedure.
The study collects several outcomes and measures each of these at several different points in time. However, the study does not pre-specify which of these is the primary outcome and nor does it pre-specify which of these are the primary assessment time. In the abstract of the paper, the authors have given prominence to the one outcome at one assessment point, which showed statistical significance. Unfortunately, conducting trials without pre-specification of primary outcomes leads increased risks of reporting that the intervention works, when it is fact does not.
Authors and editors need to be aware of the pitfalls of multiple comparisons and editors must insist that if trial protocols or registration do not pre-specify primary outcome results are interpreted with sufficient uncertainty. Abstracts should not put emphasis on one outcome when it is not the primary outcome. Whilst primary care doctors clearly wish to know if this manoeuvre is beneficial, unfortunately this trial cannot tell us. This is wasteful: both of research costs and to the patients who participated in this trial for no societal benefit. More worryingly is that...
Competing Interests: None declared.