Physician Induced Demand and Hemodialysis Treatment in Taiwan

　　誘發需求假說預測當醫療供給者面對所得損失時，會增加病人醫療使用來彌補損失。由於尿毒症的透析治療遠較藥物昂貴，供給者可能縮短藥物治療，改採透析治療來彌補損失。據此，本文檢驗當供給者前期所得降低時，本期新病患(從未進行透析治療)的透析數目是否增加。為了控制供給者難以衡量特性(如品質)，實證上採一階差分估計。利用1996－2001年的健保透析治療記錄，我們證實這樣的負向關係。平均而言，新病患彌補院所5－10%所得。這結果不論以醫師或醫院為供給者，或以3、6、12個月做為期間均成立。此外，結果顯示財團法人醫院有較大的所得效果。
　　The “supplier-induced demand (SID)” hypothesis states that health suppliers, in the face of negative income shocks, may exploit their agency relationships with patients by providing excessive care. We argue SID leads providers to compensate for their losses by substituting away from drug treatment toward more heavily reimbursed dialysis treatment for chronic renal failure (CRF) patients. We test this hypothesis by examining whether a provider’s earlier loss increases the volume of dialysis treatment for new CRF patients during the current period. Using Taiwan National Health Insurance Data between 1996 and 2001, we found this negative correlation after controlling for unobserved characteristics of providers (e.g., reputation) using a “first difference” approach. On average, a provider would compensate for 5–10% of their losses with new dialysis treatment. These results holds for bofh clinics and physicians and for periods of 3, 6, or 12 months. Finally, our results show the strongest income effect occurs for non-profit hospitals supported by enterprises.