Price Disparity of Medical Devices Between Japan and Foreign Countries
1996年の日本貿易振興会による報告と，1997年の医療経済研究機構による報告を契機に，医療材料の内外価格差問題は活発に議論され，複数の論者によっていくつかの原因が指摘されてきた。公定償還価格制度，立会いなどの付帯的サービス，業界保護的な法規制，暗黙の共謀など種々の原因が挙げられている。厚生労働省は2002年に外国価格参照制度を導入し，内外価格差の是正を試みた。しかし，2007年に出版された２つの報告によれば，内外価格差は上記の制度導入後も依然として存在していた。内外価格差を抜本的に解消する手段として，高額医療材料のコストを手技料に包括すること，薬事法規制改革による承認番号制度の見直し，行過ぎた立会いの是正などが重要と考えられる。
Price differences between Japan and the US for medical materials and how to reduce them.
INTRODUCTION
Previous reports (1996, 1997) have revealed that the market prices of medical materials in Japan were two to four times higher than those in the US. The Japanese government introduced the foreign price adjustment rule (FPA) in 2002 to reduce reimbursement prices in Japan. We aimed to investigate the current price differences between Japan and the US in the first half of 2005 and to evaluate the effectiveness of the FPA.


METHODS
The investigation was performed at two joint purchasing organizations (JPO) and a hospital group in the US, and at a university hospital in Japan. Forty-one items in 14 categories were selected in advance.


RESULTS
The price ratio (Japanese price/US price) was largest at 4.5-6.8 for percutaneous transluminal coronary angioplasty (PTCA) balloon catheters and 1.4-6.0 for vascular grafts. The price ratio was smallest at 1.2-2.4 for automatic sutures, 1.4-1.6 for Swan-Ganz catheters, and 1.5-2.3 for mechanical valves.


DISCUSSION
The price differences between Japan and the United States were found to have rather widened with the exception of the pacemaker, because their market prices decreased more markedly in the United States. The investigation suggests several problems with the FPA: (1) the determination process of reimbursement prices is inappropriate, which has made the Japanese market less competitive, (2) the FPA needs too much time for the resolution of price differences, and (3) price data collected according to the FPA lacks strictness.


CONCLUSIONS
The high prices of medical material in Japan need to be adjusted down with more appropriate measures such as the full cost or cost inclusion methods.
Lake Muzahi, Rwanda: limnological features and phytoplankton production
Lake Muhazi, a small lake of Rwanda (East Africa) was studied from 1986 to 1990. A dramatic decrease of the catch of Oreochromis niloticus (350 T y−1 in the fifties vs 30 T y−1 in 1982) suggested a loss of productivity or overfishing. In the same period, other ecological changes occurred: the submerged macrophytes regressed and there was a decrease in Secchi depth (0.65 m in 1987 vs 1.5 m in the fifties). Compared to other lakes of the same area, the plankton production seemed low. The results of the present study characterize lake Muhazi as a shallow lake with a rather unstable diurnal stratification and with slight differences in mixing regime between its eastern, deepest part and its western, shallowest part. Secchi disk depth does not vary seasonally to a large extent. The water has a rather high mineral content (conductivity of about 500 µS cm−1 at 25 °C) and low concentrations of dissolved N and P, except in the hypolimnion, where NHinf4sup+-N can be high.Two species, Microcystis aeruginosa and Ceratium hirundinella, account for most of the phytoplankton biomass, which is about 50–80 mg chlorophyll a m−2 in the euphotic zone, usually with little seasonal variation. Daily gross production estimates amount to about 6 to 9.5 g O2 m−2 d−1 with a significant difference between the two parts of the lake. Data on C:N and C:P ratio in the phytoplankton suggest that some N deficiency might occur in the eastern part. Moreover, the Zm:Zc ratio could also lead to rather low net production rates (0.21–0.25 d−1 for a mixed layer of 4 m)In conclusion, the primary production of lake Muhazi is medium for African lakes and the hypothesis that decreased planktonic production could account for a reduced fish production should be discarded. Whereas the present yield of the fishery is only 20 kg ha−1 y−1, the yield estimated from primary production ranges between 46 and 64 kg ha−1 y−1. This could be reached through proper management. Finally, some hypotheses are given to explain the ecological changes which occurred in the lake.