過去研究指出Tw-DRGs對醫院之衝擊存在差異，凸顯Tw-DRGs醫療資源之公平性及病患就醫可近性之議題。本研究探討2008 Medicare Severity DRGs（MS-DRG）所定義之主要併發症/合併症（Major Complication or Comorbidity, MCC），作為Tw-DRGs分類基礎之可行性，期Tw-DRGs符合公平合理的支付原則。本研究為2004-2006年縱貫性研究，研究對象為健保研究資料庫中呼吸系統疾病費用極端值除外之Tw-DRGs08801，089，09101及47501個案。分析與比較有MCC與無MCC兩群組醫療資源耗用程度及醫院CMI值之改變量。結果發現四個DRGs依MCC分群組之有MCC病患之平均醫療費用均顯著高於無MCC之平均醫療費用，且有MCC病患幾何平均住院天數亦顯著高於無MCC之病患之幾何平均住院天數。醫院收治有無MCC病患比例與醫院特性有關聯，醫學中心平均醫療費用顯著高於其他層級醫院，尤以公立醫學中心最高。MCC分兩群後，醫學中心比其他層級醫院CMI值增加較明顯，其中又以公立醫學中心增加最多。
本研究驗證結果MS-DRG支付制度確實依疾病嚴重度反應資源耗用程度，Tw-DRGs依MS-DRGs之MCC分類，則醫院獲得合理償付，醫療品質方能得到保障。 Considerations of beneficiary access and provider equity highlight that is important to address the issue of how to reduce the varying impact of Tw-DRGs pricing policy across hospitals in the past results. In this study, we have undertaken analyses the feasibility of refining Tw-DRGs secondary diagnoses on the basis of the Major Complication and Comorbidity (MCC) adopted by Medicare Severity DRGs (MS–DRGs). Data sources were longitudinal data from Taiwan NHI inpatients database from 2004 through 2006. The subjects with Tw-DRGs 08801, 089, 09101 and 47501 were selected but excluding outlier cases. The differences in costs of care to patients with MCC versus without MCC were compared. Changes to the case mix index were further estimated across hospitals. This study found the cost per admission for each DRGs with MCC patients was higher than that of corresponding DRG without MCC significantly (P <.0001). Geometric mean length of stay per admission for each DRG was longer in the study DRG.s with MCC. CMI increase under the MCC refined Tw-DRGs and health care costs were the highest in public tertiary care institutions that treated a large number of patients with complex conditions. The results suggest that Tw-DRGs reform should incorporate the complication and comorbidity stratification to ensure and maintain equitable payment so that hospitals do not avoid treating expensive cases or are advantaged by treating less costly conditions.