Hains A H, Baer D M
Department of Exceptional Education, University of Wisconsin-Milwaukee 53201.
J Appl Behav Anal. 1989 Spring;22(1):57-69. doi: 10.1901/jaba.1989.22-57.
A single-subject design often used to compare the effectiveness of two or more independent variables (like treatment programs) is the multielement (alternating treatments or simultaneous treatments) design. Variants of this design approximate the concurrent comparison of the effects of two or more variables (or levels of variables) by programming the variables (or levels) in rapid alternation, typically across or within daily sessions. Properly combined with conventional reversal designs, these designs can also display a variety of interaction effects, some of them worrisome, others highly desirable for the future development of the field. A worrisome model is the possibility that when Treatment B alternates rapidly with Treatment C, the effects of each will not be the same as when each is the only treatment used. A desirable model is the use of the multielement design as a fast-paced component of an otherwise conventional reversal design examining contextual control of some relationship; the possibility that some behavior responds differently to Controlling Variables A and B in Context X than in Context Y. This second possibility opens single-subject designs to the more efficient examination of all interactive effects and is highly desirable, considering the prevalence and importance of interactions in determining the limits and the generality of currently understood behavioral phenomena.
一种常用于比较两个或多个自变量（如治疗方案）有效性的单一被试设计是多元素（交替治疗或同时治疗）设计。通过快速交替安排变量（或变量水平），通常是在每天的疗程之间或之内，这种设计的变体近似于对两个或多个变量（或变量水平）的效果进行同时比较。与传统的反转设计适当地结合，这些设计还可以显示出各种交互作用效果，其中一些令人担忧，另一些则对该领域的未来发展非常有利。一个令人担忧的模式是，当治疗B与治疗C快速交替时，每种治疗的效果可能与单独使用时不同。一个理想的模式是将多元素设计用作传统反转设计的快节奏组成部分，以检验某种关系的情境控制；即某些行为在情境X中对控制变量A和B的反应与在情境Y中不同的可能性。第二种可能性使单一被试设计能够更有效地检验所有交互作用效果，考虑到交互作用在确定当前所理解的行为现象的局限性和普遍性方面的普遍性和重要性，这是非常可取的。
