方法对比

	Single-System Design	AB设计
领域	Social Work	实验设计
方法族	Process / pipeline	Process / pipeline
起源年份	2009	1960s
提出者	Martin Bloom, Joel Fischer & John G. Orme (codification in social work)	Murray Sidman; Baer, Wolf & Risley
类型	Time-series design for evaluating intervention with a single client system	Single-subject experimental design
开创性文献	Bloom, M., Fischer, J., & Orme, J. G. (2009). Evaluating Practice: Guidelines for the Accountable Professional (6th ed.). Pearson/Allyn & Bacon. ISBN: 9780205458066	Sidman, M. (1960). Tactics of Scientific Research: Evaluating Experimental Data in Psychology. Basic Books.
别名	Single-Subject Design, Single-Case Design, N-of-1 Design, Single-System Evaluation	baseline-intervention design, AB single-case design, AB phase design
相关	4	6
摘要	A single-system design is a time-series approach to evaluating practice in which a single client system — an individual, family, group, or organization — is measured repeatedly on a clearly defined target before and during (and sometimes after) an intervention. By tracking the same system over time rather than comparing a treatment group to a control group, it lets a practitioner judge whether their own intervention is associated with change in the people they actually serve. It is the methodological backbone of the 'accountable professional' tradition codified by Bloom, Fischer, and Orme.	The AB design is the simplest single-subject experimental design, consisting of two sequential phases: a baseline phase (A) in which the target behavior is observed under natural conditions without intervention, followed by an intervention phase (B) in which the treatment or manipulation is introduced. Changes in the behavior's level, trend, or variability between phases are used to infer the effect of the intervention on the individual participant.