[Calculation of drug information necessity factor of generic drugs]

The utilization of generic drugs has been promoted, but there is concern about the insufficiency of the information provided on generic drugs. To make an objective evaluation of the amount of information supplied by generic drug manufactures, we tried to quantify the information supply. The information described in the package insert and the interview form were used in the evaluation. We sent a questionnaire to 1000 randomly selected hospitals nationwide to determine the necessity of each information item in medical practice, and weighted the score allotted to each item based on replies from 524 hospitals. We applied these procedures to diclofenac sodium products and found that the score for a branded drug was 60.5 points and that for generic drugs ranged from 1.6 to 58.3 points. This indicates that there were great variations in information supply activities among the manufacturers. The Qua value, which was the ratio of the points of a generic drug per unit price in the drug tariff to the points of the branded drug, ranged from 0.1 to 2.4. We think that these procedures will make it possible to select the appropriate generic drugs in medical practice.