背景：對於醫療人員而言，安全為提供醫療服務之首要條件。就藥師而言，單位時間內的處方量愈多，將導致評估處方的時間愈少，用藥疏失的風險會增加。根據文獻，繁重的工作量亦導致未偵測到的調劑疏失的發生，而藥師人力短缺是增加用藥疏失的潛在因素。
目的：建立臺灣各醫院層級合理的門診藥事調劑服務量，並得出影響調劑作業時間之因素。
方法：本研究為橫斷性研究，以民國90至93年度醫院評鑑暨教學醫院評鑑合格名單，於地區醫院以上之執業藥師為研究對象，依處方性質分為一般處方、磨粉處方及照會處方，實地測量依據標準操作程序所花費的時間。定義完成90%處方之時間為合理調劑時間，將處方量依性質做比例換算，利用工時估算每位藥師每日調劑之合理處方量，進而推估合理門診藥事人力。並利用問卷調查標準操作程序於藥事服務現況執行率，若執行率不到60%，則進而分析限制執行因素。本研究採用描述性統計和多元線性迴歸推估合理調劑量時間與影響調劑作業因素。
結果：本研究共收集1452張有效實測處方及1251份有效問卷，依26家醫院執行結果，一張處方合理調劑時間介於7分32秒與9分54秒，推估一位藥師每日調劑處方的合理上限值為64張，每小時調劑品項數不超過36項。依52家醫院問卷調查的結果顯示，現況以處方評估及用藥指導部分執行率最不佳，主要受限於人時不足。
結論：根據本研究的結果，臺灣的門診藥師人力尚不足夠，估算合理門診人力還需現行藥事門診人力之1.03～3倍。

Background
Under-staffed pharmacy and the lack of cognitive intervention from pharmacists have been suggested as reasons for the increased risks in dispensing interacting drugs and undetected medication errors.
Objective
To evaluate the optimal dispensing volume of pharmacist at outpatient department of hospitals in Taiwan.
Methods
Between September 2006 and June 2007, we conducted a field study in hospitals in Taiwan to evaluate the time required for hospital pharmacists to complete dispensing task in accord with the standard operating procedures (SOPs) developed by pharmacy experts. Linear regressions were used to estimate the required dispensing time and manpower, adjusting for characteristics of prescriptions, pharmacists, and hospitals. Pharmacists of the participating hospitals were also surveyed for their compliance to the SOPs during daily practice and the perceived barriers to comply with the SOPs.
Result
Twenty-six institutions had participated, which included medical centers, regional, and district hospital. A total of 1452 prescriptions were measured for the dispensing time, and 1290 questionnaires from pharmacists were collected. We employed the 90 percentile of dispensing time as the essential interval for complying with SOPs, which was found to be 7 minutes and 32 seconds to 9 minutes and 54 seconds. The maximum volume for a pharmacist to dispense in accord with the SOPs was 64 prescriptions per day. Among the SOPs, the compliance rates of prescription evaluation and consultation provision to patients were found to be lower than the other procedures, which could be attributed to the high workload.
Conclusion
The current dispensing load of pharmacist in the ambulatory care settings was significantly higher than the optimal volume. The implications on quality of pharmaceutical care need to be further explored.

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