Rotman B L, Sullivan A N, McDonald T, DeSmedt P, Goodnature D, Higgins M, Suermondt H J, Young C Y, Owens D K
Department of Veterans Affairs Medical Center, Palo Alto, CA, USA.
Proc Annu Symp Comput Appl Med Care. 1995:693-7.
We are performing a randomized, controlled trial of a Physician's Workstation (PWS), an ambulatory care information system, developed for use in the General Medical Clinic (GMC) of the Palo Alto VA. Goals for the project include selecting appropriate outcome variables and developing a statistically powerful experimental design with a limited number of subjects. As PWS provides real-time drug-ordering advice, we retrospectively examined drug costs and drug-drug interactions in order to select outcome variables sensitive to our short-term intervention as well as to estimate the statistical efficiency of alternative design possibilities. Drug cost data revealed the mean daily cost per physician per patient was 99.3 cents +/- 13.4 cents, with a range from 0.77 cent to 1.37 cents. The rate of major interactions per prescription for each physician was 2.9% +/- 1%, with a range from 1.5% to 4.8%. Based on these baseline analyses, we selected a two-period parallel design for the evaluation, which maximized statistical power while minimizing sources of bias.
我们正在对一种为帕洛阿尔托退伍军人事务部综合医疗诊所（GMC）开发的医师工作站（PWS）——一种门诊护理信息系统——进行一项随机对照试验。该项目的目标包括选择合适的结果变量，并在受试者数量有限的情况下制定一个具有强大统计效力的实验设计。由于PWS提供实时药物订购建议，我们回顾性地检查了药物成本和药物相互作用，以便选择对我们的短期干预敏感的结果变量，并估计替代设计可能性的统计效率。药物成本数据显示，每位医生每位患者的每日平均成本为99.3美分±13.4美分，范围从0.77美分到1.37美分。每位医生每张处方的主要相互作用发生率为2.9%±1%，范围从1.5%到4.8%。基于这些基线分析，我们选择了两阶段平行设计进行评估，该设计在最大限度地提高统计效力的同时，将偏差来源降至最低。
