Bias in clinical trials into the effects of complementary and alternative medicine therapies on hemodialysis patients

BACKGROUND: Chronic renal failure is among the major health challenges in the world. Many clinical trials have been conducted to assess the effects of complementary and alternative therapies on hemodialysis-related outcomes. However, a number of biases may affect the results of these studies. AIMS: This study aimed to assess biases in randomized clinical trials into the effects of complementary and alternative therapies on hemodialysis patients. SETTINGS AND DESIGN: A critical review on clinical trials into the effects of complementary and alternative therapies therapies on hemodialysis patients. MATERIALS AND METHODS: This study was conducted on 114 randomized clinical trials which had been published in 2012–2017 into the effects of complementary and alternative therapies on hemodialysis patients. The Cochrane Risk of Bias Tool was employed to assess biases in the included trials. The collected data were presented using the measures of descriptive statistics, namely absolute and relative frequencies. RESULTS: Among 114 included trials, 71.05% (81 trials) had used low bias methods for random sequence generation, while 60.52% (69 trials) had provided no clear information about allocation concealment. Moreover, respecting blinding, 57.89% of trials (66 trials) were low bias. Around 60.52% of trials (69 trials) had no attrition between randomization and final follow-up assessment and 84.21% (96 trials) had apparently reported all intended outcomes. CONCLUSIONS: This study shows that 50% of randomized clinical trials into the effects of complementary and alternative therapies on hemodialysis patients have low bias. Yet, quality improvement is still needed to produce more conclusive evidence.