醫院資源投入對醫療收入的影響－以時間序列分析某醫院為例

摘　要研究目的本研究利用1999年1月至2005年7月共79筆月資料，以時間序列的方式，分析探討長期均衡下，醫院生產函數的影響因素，研究目的如下：ㄧ、探討人力資源（主治醫師、住院醫師、護理人力、醫療技術專業人員）的投入對醫療收入的影響。二、探討門診診次的投入對醫療收入的影響。三、探討病床數（一般病床、特殊病床）的投入對醫療收入的影響。四、探討手術例數（全麻手術、局麻手術）的投入對醫療收入的影響。五、探討資本設備淨值的投入對醫療收入的影響。六、建立醫院醫療收入之生產函數，尋求資源投入的最適組合。研究方法由於一般的總體時間序列資料大多不具定態性，亦即本期資料受上期資料的影響，若直接以傳統的迴歸方法估計，可能出現「假性迴歸」（spurious regression）的現象，亦即很有可能使原本毫無「因果關係」的變數之間，卻出現假性的因果關係。本研究採時間序列分析理論，是先以單根檢定（DF、ADF檢定）來判斷各變數是否為定態，再以共整合檢定判斷所有變數是否存在長期均衡的關係，同時以ARIMA模型尋求各變項短期動態調整下的穩定序列，再以逐步迴歸的方法建立醫院的醫療收入生產函數。研究結果本研究實證分析的結果，影響樣本醫院醫療收入（健保核減、浮動點值前之產值）的影響因素為：護理人力、門診診次、住院醫師、全身麻醉手術例數、局部麻醉手術例數、資本設備淨值等六項，其中護理人力為決定醫療產值之重要因素，其次為門診診次；又，護理人力、門診診次、局麻手術例數為正向關係，住院醫師、全麻手術例數、資本設備淨值為負相關。討論與建議本研究顯示，主治醫師人數的成長和醫療收入成長無顯著的因果關係，住院醫師人數增加和醫療收入呈負相關。查證過去文獻的研究結果：每萬人口醫師數在長期與全國醫療支出負相關，結果相符。另，研究發現：護理人力在長期為醫院醫療收入的重要決定因素，反應出護理人員長期之下對醫院的產值具相當的貢獻度；自健保實施總額預算制度後，雖護理人力與醫療收入正相關，但醫院額度已被限制，護理人力在長期均衡的情況下將面臨人力過剩的壓力。門診診次與醫療收入正相關，在總額限制下，醫院欲有效控制門診醫療費用的成長，減少門診診次是提早達到長期均衡最直接、有效的方式。局麻手術例數和醫療收入正相關，全麻手術例數與醫療收入負相關，本實證結果應與樣本醫院的主治醫師輪調制度有關，每次主治醫師與母院之間的輪調，在短期將顯著影響個別醫師病人數，此效應需透過時間的經過或調整，個別醫師的業務量才能達到長期的均衡。樣本醫院為區域醫院，全麻手術調整時間大過於局麻手術，輪調制度不利於住診業務，住診業務在外科系統又以手術為主要，樣本醫院的輪調制度已影響到全麻手術的長期發展，建議樣本醫院降低醫師的輪調頻率，否則長期均衡之下將影響醫院整體的住院業務。資本設備淨值（扣除折舊後的帳面價值）和醫療收入呈負相關，因設備的投資效益可延續多年，設備的投入在長期的時間趨勢下，扣除折舊費用後對醫院收入還是有正面的影響。鑒於設備有一定的耐用年限且為生產工具的一種，依本研究結果建議樣本醫院可考慮資本設備再投資，在每年的設備投資金額小於折舊提列總額的原則下，必定有利於醫院的長期均衡與發展。關鍵詞：時間序列、單根檢定、ARIMA、醫療費用、醫院收入

關鍵字

時間序列；單根檢定； ARIMA ；醫療費用；醫院收入

並列摘要

Abstract Research goal This research used one hospital charges claim data from January, 1999 to July, 2005 totally 79 months, by time series way, to analyze the effective factors of hospital production, and the research goal was as follows: First, to discuss the impact of human resources (doctor in charge, resident, nursing manpower, medical technology specialist) investment in medical income. Second, to discuss the impact of outpatient service in the medical income. Third, to discuss the impact of hospital bed number (common hospital bed, special hospital bed) investment in medical income. Fourth, to discuss the impact of surgery number (general anesthesia surgery, local anesthesia surgery) investment in medical income. Fifth, to discuss the impact of capital equipment net worth investment in medical income. Sixth, to establish production function of the hospital medical service income, in order to seek the resources investment the most suitable combination. Research technique Because the general overall time series material mostly does not have the stationary state, i.e. this issue of material last time material influence, if estimated directly by the traditional return method, possibly appears the phenomenon “the pseudo return” (spurious regression), i.e. very much has the possibility causes originally not in the least “the causal relation” between the variable, appears the pseudo actually causal relation. This research picks the time series analysis theory, first by the simple root examination (DF, the ADF examination) to judge various variables whether it is the stationary state. Then by altogether conformity examination judgment all variables whether has the long-term balanced relations, and simultaneously seeks under each variable short-term dynamic alignment by the ARIMA model the stable sequence. Finally by the method which returns gradually establishes the hospital medical income production function. Findings This research findings showed that affects the sample hospital medical service income (health insurance examines and lowers, floats in front of moving point value output value) are: the nursing manpower, the outpatient service examine the time, resident, the general anesthesia surgery number, the local anesthesia surgery number, the capital equipment net worth and so on. The nursing manpower was one important attribute for the decision medical service output value, following the time for the outpatient service; also, the nursing manpower, the outpatient service examine the time, the local anesthesia surgery number for are approaching the relations, resident, the general anesthesia surgery number, the capital equipment net worth are inverse correlations. Discussion and suggestion This research demonstrates doctor in charge the population growth and the medical income grow the not remarkable causal relation, resident the population increase and the medical income assume the inverse correlation. The past literature findings confirmed that every ten thousand population doctor counts in for a long time with the national medical service disbursement inverse correlation, finally tallies. In addition, the research discovered that the nursing manpower in for the hospital medical service income was one important determining factor, responded for a long time the nursing staff has the suitable degree of contribution to the hospital output value. Since health insurance implementation total amount budget system, the nursing manpower and the medical income are being connected, but the hospital specified amount has been limited. The nursing manpower will face the manpower surplus pressure in the long-term balanced situation. The outpatient service examines the time and the medical income is being connected. Under the total amount limit, the hospital wants the active control outpatient service medical expense the growth, reduces the outpatient service to examine the time is shifts to an earlier time achieves long-term balanced most direct, the effective way. The local anesthesia surgery number and the medical income are being connected, the general anesthesia surgery number and the medical income inverse correlation, this real diagnosis result should turn the moudulation percentage with sample hospital doctor in charge related, each time between doctor in charge and the female courtyard wheel accent, will be remarkable in the short-term affects individual doctor the patient to count. This effect will have to penetrate the time the process or the adjustment, the individual doctor's business volume will be able to achieve long-term balanced. The sample hospital is the region hospital, the general anesthesia surgery time serious offense in the local anesthesia surgery, and turns the moudulation percentage not to favor examines the service, lives to examine the service in the surgical department system take the surgery as mainly. The sample hospital wheel moudulation percentage has affected the general anesthesia surgery long-term development, suggested the sample hospital reduces doctor's wheel frequency modulation rate, otherwise long-term balanced under will affect the hospital whole to be hospitalized the service. The capital equipment net worth (deduction amortizes after the book value) and the medical income assumes the inverse correlation, because the equipment investment benefit may continue many years, the equipment investment under the long-term time tendency, after deducts amortizes the expense to have the positive influence to the hospital income. In view of the fact that the equipment has certain serviceable life also for the production tool one kind, according to these findings suggested the sample hospital may consider the capital equipment invests again, is smaller than in every year equipment investment amount amortizes proposes a row total amount under the principle, is surely advantageous to the hospital long-term balanced and the development. Key word: Time series, simple root examination, ARIMA, medical expense, hospital income