World J Mens Health.  2013 Aug;31(2):157-162.

A Quality Analysis of Randomized Controlled Trials about Erectile Dysfunction

• Chung JH
• Lee JW
• Jo JK
• Kim KS
• Lee SW

Abstract

PURPOSE
A low quality clinical trial could produce errors, and these errors could, in turn, distort the results of the clinical trial. To avoid applying distorted results of trials clinically, a quality analysis of clinical trials is needed.
MATERIALS AND METHODS
We selected randomized controlled trials (RCTs) about erectile dysfunction (ED) conducted in Korea using Medline and KoreaMed. Quality assessment of selected RCTs was performed using three assessment tools (Jadad scales, van Tulder scale, Cochrane Collaboration Risk of Bias Tool [CCRBT]).
RESULTS
The first RCT about ED conducted in Korea was published in 2002. Since 2002, a total of 20 RCTs have been published in medical journals. Among the 20 articles, only 1 article was found to have a low risk of bias according to the CCRBT. On the Jadad scale, there were 17 high quality articles, while 19 articles were assessed as high quality by the VTS. Only 2 RCTs described the randomization method adequately. Only 1 RCT presented allocation concealment.
CONCLUSIONS
A low quality clinical trial could produce errors, and these errors could, in turn, distort the results of the clinical trial. To avoid applying distorted results of trials clinically, a quality analysis of clinical trials is needed. The quality of RCTs was found to be high because almost all of the selected RCTs were double blinded studies. However, the quality of RCTs was inadequate with regard to the lack of randomization and absence of allocation concealment. Therefore, performing adequate randomization and adding a description of the appropriate concealment of allocation may improve the quality of RCTs.

Keyword

Randomized controlled trial; Journal article; Erectile dysfunction

MeSH Terms

Bias (Epidemiology)
Erectile Dysfunction
Korea
Male
Random Allocation

Figure

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  Fig. 1 Medical institution of corresponding author.

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