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Randomized controlled trials on erectile dysfunction: quality assessment and relevant clinical impact (2007–2018)

Abstract

The aim of this study was to assess the quality of randomized controlled trials (RCTs) on erectile dysfunction (ED) conducted from 2007 to 2018. We searched for RCT original articles on ED published between 2007 and 2018 using PubMed, Embase, and Cochrane Library databases. RCT quality assessment was performed using Jadad scale, van Tulder scale, and Cochrane Collaboration’s Risk of Bias Tool. The effects on RCT quality of including treatment methods, funding sources, institutional review board (IRB) approval statements, and intervention description to the studies were assessed. Blinding and allocation concealment were described in 67.9 and 8.7% of the RCTs, respectively. Blinding tended to decrease, but a sharp rise in blinding was observed in 2011–2012 and allocation in 2017–2018. Funding statement inclusion (60.3% overall) and intervention description (96.4% overall) tended to increase steadily. IRB statement inclusion (78.3% overall) increased (p = 0.05). Jadad scores rose significantly until 2011–2012 but decreased thereafter except 2017–2018 (p = 0.09). RCTs with funding statements had higher Jadad and van Tulder scores than unfunded RCTs (p < 0.01 and 0.02, respectively). Quality improvement has observed from 2007 to 2012 and 2017 to 2018 with Jadad scale because of increased funding, multicenter studies, and intervention description.

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Correspondence to Seung Wook Lee.

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Kim, K.S., Chung, J.H. & Lee, S.W. Randomized controlled trials on erectile dysfunction: quality assessment and relevant clinical impact (2007–2018). Int J Impot Res 32, 213–220 (2020). https://doi.org/10.1038/s41443-019-0143-x

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