Researchers tested their SARS vaccine on four African green monkeys, with another four in the control group. |
Dr Duncan found that only one of the groups, the third group, showed any apparent effect in comparison with the control group. |
A further 932 were recruited from the public to act as a control group for comparison. |
The control group was maintained in a similar chamber ventilated with filtered air. |
Direct evaluation cannot be done because very few ganzfeld studies have included a control group. |
The possibly calming effect of having family present for the control group during the intervention could have played a part in the reaction. |