病歷完成時效對DRG與病例組合指標之影響－以某醫學中心為例

The Influence of Medical Records’ Completion Timing on DRG＆Case Mix Index－A Case Study of a Private Medical Center

許淑珍(Shu-Chen Hsu)

指導教授 ： 廖宏恩博士

亞洲大學/健康學院/健康管理研究所/碩士(2005年)

摘要

目前全民健保總額制度下的論量計酬制，對於醫療資源有效率的重分配效果有限，所以健保局規劃朝向多元化與前瞻性支付制度發展，並擬於民國九十五年住院部份採用診斷關係群（Diagnosis Related Group, DRG）作為診療項目的支付基準。DRG的歸類係根據ICD-9-CM碼，若病歷未及時完成，將導致編碼不完整或錯誤，進而可能影響醫院的財務收入。
本研究主要探討病歷未於申報前及時完成對疾病分類碼不一致性、DRG與病例組合指標（Case Mix Index, CMI）之影響，以及比較在期限內完成病歷之獎勵辦法實施後疾病分類碼不一致情形，以某醫學中心之出院病歷為對象進行研究。因93年9月開始提高獎勵辦法，所以選取93年6-8月及9-11月兩組出院病歷為個案組；而以92年6-8月及9-11月為對照組。利用健保局申報之住院資料檔，與申報後病歷完成之疾病分類檔比對，篩選出疾病分類碼不一致個案，運用健保局第一版DRG編審規則進行分類，比較申報前後DRG碼與病例組合指標（CMI）之變化。統計部分採用Brio軟體、Microsoft Excel、SPSS10.0版套裝統計軟體進行描述性分析與配對t檢定。
研究結果發現病歷未完成的確會影響疾病分類編碼不一致，其分佈及影響如下：（1）申報前後各科疾病分類碼不一致性6%至55%，整體不一致性19%至26%，其中復健科、家庭醫學科、血液腫瘤科、胸腔科、心臟科、乳房外科、胸腔外科、消化外科、心臟血管外科不一致性比例較高。造成疾病分類碼不一致主要原因是主診斷編碼不一致、遺漏次要診斷、重要處置遺漏未編碼等。（2）申報前後疾病分類碼不一致性造成DRG的改變為6.3%至9.0%，全院CMI值申報後較申報前提高1.14%至2.06%，經配對t檢定結果皆達統計上顯著差異，且次診斷數申報後較申報前高。（3）提高獎勵措施後，未完成病歷比例，住院醫師由實施前1.6%降至實施後0.03%，主治醫師由7.5%降至6.5%，疾病分類碼不一致性由26%降至19%，獨立樣本t檢定結果，其變化達統計上顯著差異。另一方面，因DRG改變導致相對權值提高，其潛在效益增加，所以若實施DRG支付制度，本研究醫院每年可減少損失近550萬元。
本研究建議衛生主管機關統一病歷書寫規範、建立完整的審查機制、提昇疾病分類編碼一致性，建議醫院管理者加強未完成病歷之管理，實施同步審查，監控編碼正確性與費用異常管理。最後本研究亦歸納疾病分類碼不一致原因及常見錯誤或通則提供參考。

關鍵字

診斷關係群 ； 前瞻性付費制度 ； 病例組合指標 ； 病歷管理

並列摘要

Currently, fee-for-service based reimbursement scheme has led to inefficient distribution of medical resources. Therefore, Bureau of National Health Insurance intends to develop other predictable budget scheme, including Prospective Payment System (PPS). In addition, the authority plans to implement new payment standard for inpatient medical services based on Diagnosis Related Groups (DRGs) in year 2006. The DRG classification principle is based on ICD-9-CM code. Thus, if a medical record can’t be completed by the deadline of filing insurance claims, it may lead to incomplete or inaccurate coding, and further impacts on the financial revenues of a hospital.

The purpose of this thesis aims to discuss the inconsistency of ICD coding as well as the impacts on DRG and Case Mix Index (i.e, CMI) when medical records were not completed and reported by scheduled time of filing insurance claims. Furthermore, this study analyzed the effects of a rewarding policy for in-time completion of medical records. The discharged medical records of a private medical center were collected as our sources of data. Since the rewarding policy was put into operation on September, 2004, this study collected discharged medical records of June to August and September to November of Year 2004 as our case groups, with discharged medical records of June to August and September to November of Year 2003 chosen as our compared groups. This study employed Brio Software, Microsoft Excel, and SPSS software (version 10th) to proceed various binary analyses. The major findings and suggestions show as follows.

(1) Incomplete medical records by the scheduled time of filing insurance claims have led to overall inconsistent coding from 19% to 26%, depending on the case or comparison groups, and further inconsistent coding from 6% to 55%, depending on medical departments. Among these medical departments, Dept. of Rehabilitation, Family Medicine, Hematology, Chest Medicine, Cardiology, Breast Surgery, Thoracic Surgery, Digestive Surgery, and Cardiovascular Surgery showed higher percentage of inconsistent coding. In addition, inconsistency of major diagnosis, omission of secondary diagnosis, and omission left on major procedure coding constitute most of the inconsistency.
(2) Inconsistent ICD coding led to the significantly changes of DRG ranged from 6.3% to 9%. Also, the value of CMI significantly increased from previous 1.14% to 2.06% afterward. The same situation applied to the numbers of secondary diagnosis coding .
(3) The reward-driven policy statistically worked for residents from 1.6% of incomplete medical records to 0.03%. It also worked for attending physicians from 7.5% of incomplete medical records to 6.5%. The percentage of inconsistent ICD coding decreased significantly from 26% to 19%. Moreover, the increased relative values of DRGs, enlarged potential revenues. The study hospital, as an example, was estimated to avoid potential loss of nearly 5.5 million NT dollars, should DRG-based payment system was implemented at this moment.

This study suggests that the health authority should provide a consistent, unified medical record writing model, as well as more thorough peer-review mechanism to improve the consistency of ICD coding. Meanwhile, we also suggest that the hospital administration should use ways and means to manage incomplete medical records, as well as more monitoring toward inaccurate ICD coding. At last, this study make a contribution by offering a useful guide to common causes of ICD coding.

Key word：Diagnosis Related Groups (DRGs)
Prospective Payment System (PPS)
Case Mix Index (CMI)
Management of Medical Records

並列關鍵字

Diagnosis Related Groups (DRGs) ； Prospective Payment System (PPS) ； Case Mix Index (CMI) ； Management of Medical Records

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