Sir.—In Professor Kitch's1 editorial comments about my article2 on diphtheria and tetanus toxoids and pertussis (DTP) vaccine litigation, he stated that the article "contributes little to useful 'quantitation'" because: (1) it "provides almost no information about the data set," (2) "its defect is more than one of omission," (3) one of its statements "is false," (4) it provided information on a "misleading indicator" (complaints filed), and (5) it did not contain "important and useful information that could have been obtained about the complaints that have been filed." He pointed out numerous types of information that would have been useful, including "the court in which the cases were filed," "the basis on which liability is claimed," and "the identity of the lawyer representing the plaintiff." He then went on to say that a physician could make more of a contribution if "instead of addressing legal issues, he addressed