多時段預約系統之看診名額與約診時間規劃

Designing Quota Size and Patient Arrival Time in Multiple Block Systems

張瑋庭(Wei-Ting Chang)

指導教授 ： 黃奎隆

國立臺灣大學/工學院/工業工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.03166

摘要

為了有效的管理醫療門診，規劃病患預約時間為很重要的課題，在降低病患等候時間、提升病患對於看診滿意度的同時，可節省門診空間成本。本研究針對病患等候時間問題設計病患預約系統，目的為減少病患等候看診時間，系統中考量兩種平均服務時間不同的病患：追蹤型與首次門診病患，且將病患等候時間分為兩類：(1)等候天數：病患有看診需求至實際看診當天間的等候時間，以天為單位，(2)在院等候時間：為病患抵達門診至實際看診的時間。為有效減少這兩種病患等候時間，本研究提出一兩階段病患預約系統模型，利用兩階段分別針對不同類型的等候時間進行探討。本研究假設病患會準時抵達門診、病患服務時間服從指數分配。
第一階段的病患名額指派系統，概念為將一天的開放時間切割等距小時段，利用動態規劃方法，計算如何將兩種病患當日開放名額分配至各個小時段，以求得最低的「病患等候時間超過可容忍時間機率(POTT)」，以及最佳的病患配置，降低病患在院等候時間。第二階段為逐日預約排程系統，利用階段一之結果做為每日門診的開放名額，使用模擬方法比較三種不同預約排程規則之考量病患預約即時性的績效表現，本研究使用的預約規則為臺大醫院腹部超音波門診目前使用的FCFS規則、學者Vermeulen(2009)提出之FCFSBU規則，以及本研究改善FCFSBU規則所提出的IFB規則、IFBP規則，第二階段目的為希望降低病患等候天數。
本研究結果比較兩種不同的情境，第一種為在等距小時段設定下，比較FCFS規則、FCFSBU規則和IFB規則的績效結果，第二種為IFB規則使用在醫院目前時段設定也就是將一天只分為上、下午兩個大時段，和30分鐘小時段的情況下，各績效指標的表現。發現在等距小時段模型設定下，IFB規則皆優於其餘兩種規則，且較不易受到進入系統病患人數影響，績效表現較其餘規則穩定；在IFB規則使用至醫院本身時段設定與切割30分鐘等距小時段的結果比較上，結果顯示小時段可明顯的改善病患在院等候時間，而雖然小時段之病患等候天數略高，但整體而言，小時段對於病患等候情況還是較大時段改善。

關鍵字

預約系統 ； 配額預約 ； 動態規劃 ； 系統模擬 ； 病患延遲

並列摘要

In this study, we consider appointment scheduling for a medical service with scarce resource while patients are required to make a reservation ahead. Two kinds of patients are observed with different average service times: the follow-up patient and outpatient. In addition, two types of patient waiting time are considered: waiting time of days and waiting time in the clinic. Waiting time of days is the difference between the time a patient requests an appointment and the time of that appointment. Waiting time in the clinic is the difference between a patient's waiting time and the time he/she actually served. To effectively reduce the waiting time for patients, we propose a two-stage appointment scheduling system.
The first stage of the system deals with the waiting time in the clinic and is about quota assignment. We divided the opening hours into the same length of time slots and determine the best quota for each time slot, in order to achieve the lowest probability of patients waiting time exceeding a given tolerable time (POTT). Dynamic programming is used in this stage. The second stage is daily appointment system which addresses the waiting time of days. We consider system workload of each time slot, patient priorities and FCFS principle in IFB rule when scheduling appointments. In this stage, we use a simulation model to compare the proposed appointment policy with other two policies with four performance measures: patient delay proportion, average delay days, maximum delay days and standard deviation of delay days. The simulation data are collected from historical data of National Taiwan University Hospital.
Furthermore, we examine the proposed appointment rules under two different scenarios. The first scenario is we compare the performance of rules when we divided open hours into time slots. In the second scenario, we investigate that whether the open hours are divided into time slots with shorter time length or not will affect the performance of IFB policy. In conclusion, IFB rules performance is better than other two rules, and less likely to be affected by the number of patients entering the system. In the second scenario, the results show that schedule patients by time slots can significantly improve patients’ waiting time before treatment although the waiting time of days are slightly higher.

並列關鍵字

appointment system ； quota assignment ； dynamic planning ； simulation ； delay

參考文獻

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