A 2005 review, published in The Lancet, of six trials of conventional medicine and 8 studies of homeopathy had revealed that homeopathic medicines are just placebo.
George Lewith, Professor of Health Research at Southampton University claims that the conclusions are 'not' reliable.
"The review gave no indication of which trials were analysed nor of the various vital assumptions made about the data," the Lancet quoted Lewith, as saying.
"This is not usual scientific practice. If we presume that homeopathy works for some conditions but not others, or change the definition of a 'larger trial', the conclusions change.
"This indicates a fundamental weakness in the conclusions: they are NOT reliable," he added.
The 8 larger higher quality trials of homeopathy were all for different conditions, if homeopathy works for some of these but not others the result changes, implying that it is not placebo.
The researchers have criticised the review for being based on loose assumptions. Doubts remain on the unpublished criteria used in the review, including the definition of 'higher quality'.
The review was led by Prof Matthias Egger of the Department of Social and Preventive Medicine at the University of Berne, who started with 110 matched clinical trials of homeopathy and conventional medicine, reduced these to 'higher quality trials' and then to 8 and 6 respectively 'larger higher quality trials'.
It showed 'weak evidence for a specific effect of homoeopathic remedies, but strong evidence for specific effects of conventional interventions'.
The researchers claim that comparison with conventional medicine was meaningless: the original 110 trials were matched, but matching was lost after they were reduced to 8 and 6.
They claim that the review was based on a series of hidden judgments unfavourable to homeopathy.
The current evidence suggests that homeopathy is effective for a various conditions including allergies, upper respiratory tract infections and 'flu, but further research is required.