New prescription medications are a primary driver of spending growth in the United States. For patients with severe mental illnesses, second generation antipsychotic (SGA) medications feature prominently. However, many SGAs are costly, particularly before generic entry, and some may increase the risk of diabetes. Because physicians play a prominent role in new prescription adoption, understanding their prescribing behaviors is policy-relevant. Several features of prescription data, such as different antipsychotic choice sets over time, variable physician prescription volumes, and correlation among drug choices within physicians, complicate inferences. We propose a multivariate Bayesian hierarchical model with piecewise random effects to characterize the diffusion of new antipsychotic drugs. This model captures the complex prescriber-specific relationships among the different diffusion processes and takes advantage of the Bayesian paradigm to quantify uncertainty for all parameters straightforwardly. To evaluate the prescribing patterns for each physician, we propose various indices to identify early new SGA adopters. A sample of nearly 17,000 U.S. physicians whose antipsychotic drug prescribing information was collected between January 1, 1997 and December 31, 2007 illustrates the methods. Determinants of high prescription rates and adoption speeds of new SGAs included physician sex, age, hospital affiliation, physician specialty, and office location. Large within- and between-provider variations in prescribing patterns of new SGAs were identified. Early adopters for one drug were not early adopters for another drug. This article is protected by copyright. All rights reserved.

中文翻译：

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表征新型抗精神病药物扩散的贝叶斯层次模型

新的处方药是美国支出增长的主要驱动力。对于患有严重精神疾病的患者，第二代抗精神病药物 (SGA) 具有显着的特点。然而，许多 SGA 的成本很高，尤其是在仿制药上市之前，有些可能会增加患糖尿病的风险。由于医生在新处方采用中发挥着重要作用，因此了解他们的处方行为与政策相关。处方数据的几个特征，例如随着时间的推移不同的抗精神病药物选择集、可变的医生处方量以及医生内部药物选择之间的相关性，使推论复杂化。我们提出了一种具有分段随机效应的多元贝叶斯层次模型来表征新抗精神病药物的扩散。该模型捕捉了不同扩散过程之间复杂的处方特定关系，并利用贝叶斯范式直接量化所有参数的不确定性。为了评估每位医生的处方模式，我们提出了各种指标来识别早期的新 SGA 采用者。在 1997 年 1 月 1 日至 2007 年 12 月 31 日期间收集了近 17,000 名美国医生的抗精神病药物处方信息的样本说明了这些方法。新 SGA 的高处方率和采用速度的决定因素包括医生性别、年龄、医院隶属关系、医生专业和办公地点。确定了新 SGA 的处方模式在提供者内部和提供者之间的巨大差异。一种药物的早期采用者不是另一种药物的早期采用者。本文受版权保护。版权所有。