y contrast with the weaknesses of anecdotal observations from case series, the power of randomised clinical trials for deciding the benefit of therapy has become increasingly evident and indisputable world wide. Nowadays, to argue against the validity of this assertion may seem superfluous; however, a recent paper reported by Del Brutto1 regarding treatment in neurocysticercosis ignores basic procedures for well performed clinical trials by using inappropriate and misleading methodology to evaluate medical therapy.
By definition, a clinical trial is a prospective study comparing the effect and value of treatment against a control in human subjects. The main drawback of Del Brutto’s report is that it does not include a control group against which the intervention group is compared; therefore, its results are definitely flawed. Additionally, a basic experimental study design requires at least minimal information regarding inclusion and exclusion criteria, randomisation, and definitions of response or outcome variables. This information is not provided by Del Brutto’s report; its design fails to protect against potential bias in patient selection or evaluation of outcome. The definition of subarachnoid cysterci used by Del Brutto was based on “appearance on CT of hypodense cystic lesions located over the convexity of the cerebral hemispheres, the sylvian fissure, or the CSF cisterns at the base of the brain”. It is well known that there are many other diagnostic possibilities to be considered in the differential diagnosis of subarachnoid hypodense lesions.2 3 Besides, CT is not a reliable procedure for diagnosing subarachnoid cysterci, as is MRI. In fact, we cannot be completely sure, for example, that the CT images shown in the report of Del Brutto correspond to subarachnoid cysterci. If we were to use MRI on this patient, they might correspond to a parenchymal cyst which resolved as a reflection of the natural history of the condition. There is no evidence that objectively confirms or rejects this assertion.