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 multiplebaseline 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.