The phrase "a sham case" is correct and usable in written English.
It can be used to describe a situation or legal case that is not genuine or is intended to deceive.
Example: "The lawyer argued that the evidence presented was merely a sham case designed to mislead the jury."
Alternatives: "a fraudulent case" or "a bogus case".
To inform the design and assess selection bias of a future case-control study of rotavirus vaccine effectiveness (VE) in western Kenya, we performed a sham case-control study evaluating VE of pentavalent vaccine (DTP-Hib-HepB) against rotavirus acute gastroenteritis (AGE).
The advantage of the bias-indicator approach is that it can be done contemporaneously with an actual case-control study of rotavirus AGE cases, which cannot be done for a sham case-control study like ours due to the co-administration of most EPI vaccines.
In all sham cases, the initial surgical procedure was as described above.
Bias-indicator studies are a different type of sham case-control study than we performed, in that the sham is not the exposure (i.e. vaccine) but rather the outcome (i.e. type of gastroenteritis).
Aside from the expected tract marks, there was nothing remarkable about the brains of the remaining seven Sham cases, with the exception of one other ShamHpc case (with a small patch of unilateral atrophy in the parietal cortex).
Sham case-control or pilot studies before vaccine introduction can be useful in designing case-control VE studies.
Sham case-control studies, like real ones of vaccine effectiveness, are not useful in settings of extremely high vaccine coverage.
The findings from this sham case-control study will enable future rotavirus vaccine case-control studies in Kenya to be designed more efficiently.
In severe cases, the cortical thickness of the ipsilateral hemisphere was significantly reduced by ~40% compared to sham cases (P < 0.001).
Our sham case-control study provided several important lessons that can be applied to a case-control study of rotavirus VE in the same setting after vaccine introduction, expected in 2014 [ 2].
For the sham case-control study, we did not expect to find statistically significant "effectiveness" of the pentavalent vaccine against rotavirus AGE, but rather to determine if the study found a point estimate that gave an indication of potential bias (i.e. the odds ratio was significantly different from 1.0).
