Homeopathy for mental fatigue: lessons from a randomized, triple blind, placebo-controlled cross-over clinical trial

BMC Complementary and Alternative Medicine

Hugh MacPherson²  Debbie Gooch¹  J Martin Bland²  Raj Karsandas²  Michael Emmans Dean² 

[1] Dept. of Psychology, University of York, York YO10 5DD, UK;Dept. of Health Sciences, University of York, York YO10 5DD, UK

关键词: Stroop test;    Kali phos 6x;    Mental fatigue;    Crossover study design;   

Others  :  1231991
DOI  :  10.1186/1472-6882-12-167

 received in 2012-03-30, accepted in 2012-09-19,  发布年份 2012

【 摘 要 】

Background

Difficulty in controlling attention can lead to mental fatigue in the healthy population. We identified one trial reporting a benefit in patients’ attention using a homeopathic formula preparation. One component of the preparation was potassium phosphate, widely available off the shelf as Kali phos 6x for cognitive problems. The aim of this exploratory trial was to assess the effectiveness of Kali phos 6x for attention problems associated with mental fatigue.

Methods

We recruited student and staff volunteers (University of York) with self-reported mental fatigue, excluding any using homeopathy or prescribed stimulants, or with a diagnosis of chronic fatigue syndrome. In a triple blind, cross-over, placebo-controlled clinical trial, 86 volunteers were randomized to receive Kali phos 6x or identical placebo 10 minutes before taking a psychological test of attention (Stroop Colour-Word Test). One week later they were crossed over and took the other preparation before repeating the test.

Results

We found no evidence of a treatment effect in a comparison of Kali phos 6x with placebo (Kali phos minus placebo = −1.1 (95% CI −3.0 to 0.9, P = 0.3) Stroop score units, Cohen effect size = −0.17) even when allowing for a weak period effect with accuracy scores in the second period being higher than those in the first (P = 0.05). We observed a ceiling effect in the Stroop test which undermined our ability to interpret this result.

Conclusions

Kali phos 6x was not found to be effective in reducing mental fatigue. A ceiling effect in our primary outcome measure meant that we could not rule out a type II error. Thorough piloting of an adequate outcome measure could have led to an unequivocal result.

Current Controlled Trials

ISRCTN16521161

【 授权许可】

   
2012 Dean et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

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