Objectives : Pharmaceutical companies in Japan can attach pharmacoeconomic (PE) data to their application for new drug prices covered by the National Health Insurance (NHI) system since 1992. To examine the present state of PE studies in Japan by investigating the situation of PE data attachments and their details and also to identify problems concerning how to reflect the PE information in new drug pricing, a questionnaire-based survey of pharmaceutical companies was conducted.
Method : The survey covered 115 drugs filed by the members of the Japanese Pharmaceutical Manufacturers Association (JPMA), which are among the 137 drugs listed between June 20, 1997, when the NHI drug price formula was published, and November 17, 2000. Questionnaires were returned on 114 of the 115 drugs studied and the response rate was 99%.
Results : PE data was attached to 37 of the 114 drugs (32%) at the time of application. The ratio of applications accompanied by PE data tended to be decreased from 1998. No significant relation was observed between a premium for a drug and the attachment of PE data. The most common method used in the attached PE data was cost-effective analysis (14 of 37 drugs ; 38%), followed by cost-benefit analysis (7 drugs) and cost-minimization analysis (6 drugs). Cost-utility analysis was not applied to any of the 37 drugs.
Discussion : Compared with overseas PE studies, Japanese studies were found to be less comparable with one another due to the lack of a uniform system of research and reporting results. Other problems observed included insufficient epidemiological data for analysis and difficulty in the cost data collection. The questionnaire-based survey revealed that Japan needs to set guidelines for PE studies and to establish epidemiological and cost databases for these research activities. It also suggested the necessity of reviewing the present method of clinical tests so that economic parameters for PE analysis and QOL may be obtained from these tests.

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Objective : To outline new methods developed in Medicines Control Agency (MCA) in the UK, Food and Drug Administration (FDA) in the USA and WHO Uppsala Monitoring Centre (UMC) to detect signals from spontaneous reports on suspected drug reactions.
Methods : Presentations in the Signal Generation Symposium (Southampton, UK, June 2001) and related articles identified by hand searching were examined.
Results : All of the 3 methods compare the number or probability of reports on a particular drug-event combination with the expected number or probability for the combination. For example, in the MCA's method, the expected number is estimated as (the total number of reports on a drug) × (the fraction of an event among all spontaneous reports). A signal is detected when Proportional Reporting Ratio (PRR) defined as the ratio of observed/expected numbers>2 and the corresponding chi-square value> 4. In the FDA's method, the observed number of a drug-event combination is supposed to have a Poisson distribution with a mean of μ and the signal score is defined as the expected value of a random variable λ=μ/E where E is the expected number of reports on that combination. A signal is detected when signal score>2. The “Information Component” (IC) in the UMC's methods is estimated from the ratio of posterior to prior probabilities for a particular drug-event combination. A signal is detected when the 95% confidence interval for the IC is positive and does not include 0.
Conclusion : New methods outlined in this article require further theoretical development and its application to the analysis of spontaneous reports.

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