市場競爭對醫師行為的影響—以西醫基層診所為例

Abstract

許多國內外的研究發現，在醫療市場競爭程度高的地方，醫師會訂定較高的價格；此外，由於病患與醫師間的資訊不對稱，可能讓醫師有機會誘發需求。 本研究目的為評估市場競爭程度對醫師行為的影響，所討論的醫師行為包含兩個部份：醫師訂價行為和供給者誘發需求行為。本研究以診所醫師人口比（分為低中、高三組）來測量地區的競爭程度，訂價是以診所醫師向民眾看診時所收取的費用來測量，供給者誘發需求則以醫師申報資料與醫師吩咐回診比例來測量。資料來源取自2005年全民健保調漲部份負擔之民眾調查、內政部統計資料、中研院社會意向調查和國衛院全民健保資料庫，並以整理合併後的50個次醫療區作為分析單位。 初步分析結果顯示，診所醫師收費價格介於85~176元之間，吩咐回診比例約在0%~15%之間，診所醫師人口比（用來代理市場競爭程度）則介於3.1~7.6之間。以迴歸模型分析，結果顯示，在控制該區醫師個人特質與都市化程度後，市場競爭程度對於醫師收費價格沒有顯著的影響；此外利用醫師申報資料（醫師每月申報件數、平均每件申報金額）和醫師吩咐回診比例以驗證診所是否有供給者誘發需求的現象，在控制地區醫師個人特質和人口特性後，競爭程度高較競爭程度低的地區，醫師每月申報件數較少，但每案件申報的金額較多，推論不同的競爭程度可能會導致不同的醫師行為。 本研究結論為台灣的市場競爭程度不會影響診所醫師的訂價行為，也沒有發現支持供給者誘發需求的證據。良性的競爭可促進產業的發展，故建議衛生主管機關應該審慎評估醫療市場的競爭對於供給者行為的改變。

Many studies both in Taiwan and foreign countries found physicians could set higher price in the regions of high competition level. Furthermore, because of the information asymmetry between patients and physicians, physicians may have opportunities to induce demand. The objective of this study is to evaluate the effect of market competition on physician behavior—using community clinics in Taiwan as an example. This study includes two parts: physician pricing behavior and supplier-induced demand. This study uses the number of clinical physicians per 10,000 populations to measure the competition level among regions (which were divided into low, medium, and high level groups). We use clinics’ charges to measure physician pricing behavior; and we use the clinics’ claim data (i.e. the volumes and expenses) and the rates of physician-initiated re-visit to measure supplier-induced demand. The data came from several sources: “2005 Outpatient Cost-sharing Increase Survey”, “The statistics of the Ministry of the Interior of 2005”, “The Academia Sinica Taiwan Social Image Survey”, and “National Health Insurance claim data of National Health Research Institutes”. In this study we combined the medical regions nation-wide into fifty sub-medical regions as our analysis unit. The preliminary result shows that the price charged by community clinics ranged between 85-176 NTD, the rates of physician-initiated re-visit is between 0%-15%, and the number of clinical physicians per 10,000 populations is between 3.1-7.6. Results from the regression models show that after controlling for physicians characteristics and the area urbanization, the market competition level has no significant impact on the average price of physician visit. Furthermore, we tested the possibility that physicians induced demand by using the NHI claim data (number of visit per month, average cost per case) and the rates of physician requested follow-up consultations. After controlling for regional and physician characteristics, results indicates that physician in higher level of competition claim fewer visits per month but higher cost per case. Therefore, the result inferred that different levels of competition may lead to different physician behaviors. The study concludes that Taiwan's healthcare market competition may not affect the clinic physician’s pricing behavior; we also found no support for the supplier-induced demand. Healthy competition can promote the development of the industry, therefore, it is suggested that the health authority should monitor the healthcare market competition and the supplier behavior changes.