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A fragility index analysis of clinical trials evaluating low-intensity extracorporeal shockwave therapy for erectile dysfunction


Erectile dysfunction is a common sexual dysfunction that affects a significant proportion of men. Low-intensity extracorporeal shockwave therapy has been evaluated in multiple clinical trials as a therapeutic option for men with erectile dysfunction. The robustness of these clinical trials is not well defined, as the trials are hindered by inconsistent treatment protocols, small study arm size and short follow-up intervals. The fragility index is a statistical analysis which is used to evaluate the robustness of clinical trials. It is calculated by evaluating the minimum number of patients in a given trial arm that would be required to have an alternative outcome to alter the statistical significance of the results. The lowest fragility index in statistically significant trials is 1, meaning that if just one participant experienced an alternate outcome, the results would no longer achieve statistical significance. The upper limit is determined by the number of participants in a given arm of the trial. Herein, a scoping review of clinical trials evaluating the efficacy of low-intensity extracorporeal shockwave therapy in erectile dysfunction to determine the fragility index of trials with clinically significant results. We hypothesized that the fragility index would be low, indicating the results are less robust and generalizable.

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The data that support the findings of this study are available upon request from the corresponding author. The data can be made available for reasonable requests and subject to confidentiality agreements and ethical considerations. Any additional data that may be required to validate the findings of this study will be made available upon reasonable request.


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Funding for this project was provided by the National Institute of Health Grant R01 DK 130991 to RR at the University of Miami. The authors otherwise have no financial disclosures.

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Authors and Affiliations



JW, FP, ND, AG, BL, MCSA, AM, TK, AB, and RR all made significant contributions to this research study. JW, AB, and RR contributed to the conceptualization and design of the study. JW, BL, and MCSA were involved in data collection and analysis. MCSA, AM, TK, AB, and RR contributed to the interpretation of the data and provided critical insights. JW, FP, AG, and RR were involved in writing the initial draft of the manuscript. All authors critically reviewed and revised the manuscript for important intellectual content. JW, FP, and RR supervised the overall research project. All authors have read and approved the final version of the manuscript.

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Correspondence to Joshua White.

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White, J., Petrella, F., Deebel, N. et al. A fragility index analysis of clinical trials evaluating low-intensity extracorporeal shockwave therapy for erectile dysfunction. Int J Impot Res (2023).

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