Regulated randomization: A potentially sharper analytical tool for the multiple-baseline design

A dual-randomization procedure, regulated randomization, is proposed for behavioral and educational interventions that incorporate the logic of single-case multiple-baseline designs. The new approach is sharper conceptually and methodologically than previously developed approaches in that regulated randomization maintains the basic integrity of the multiple-baseline design (namely, the systematically staggered introduction of the intervention across the experimental units) while being statistically practicable with fewer units (N < 4). Moreover, previously suggested nonparametric analyses of multiple-baseline data can be subsumed by a general regulated randomization formula, The regulated randomization approach provides researchers with a flexible analytic tool that can take into account specific substantive, methodological, and statistical trade-offs.