Toxic shock and tampons. Evaluation of the epidemiologic evidence.

The main evidence that tampons are an etiologic cofactor in the development of toxic shock syndrome (TSS) comes from epidemiologic case-control studies. The patients chosen as cases in those studies were assembled from reports submitted to health agencies in response to publicity that may have influenced physicians to diagnose TSS and to submit reports particularly in situations where the patient was a menstruating tampon user. When the submitted reports were checked for fulfillment of TSS diagnostic criteria, and when cases or controls were asked about antecedent tampon usage, suitable scientific precautions were not used to achieve "blinded" objective decisions. Since these biases would have distorted the statistical relationships, the etiologic role of tampons in TSS has not been scientifically proved.