Alternative Designs for Testing Speech, Language, and Hearing Interventions: Cluster-Randomized Trials and Stepped-Wedge Designs

Purpose: Individual-randomized trials are the gold standard for testing the effi-cacy and effectiveness of drugs, devices, and behavioral interventions. Health care delivery, educational, and programmatic interventions are often complex, involving multiple levels of change and measurement precluding individual ran-domization for testing. Cluster-randomized trials and cluster-randomized stepped-wedge trials are alternatives where the intervention is allocated at the group level, such as a clinic or a school, and the outcomes are measured at the person level. These designs are introduced along with the statistical implications of similarities among individuals within the same cluster. We also illustrate the parameters that have the most impact on the likelihood of detecting intervention effects, which must be considered when planning these trials.Conclusion: Cluster-randomized and stepped-wedge designs should be consid-ered by researchers as experimental alternatives to individual-randomized trials when testing speech, language, and hearing care interventions in real-world settings.

Automated summary

Cluster-randomized trials and cluster-randomized stepped-wedge trials are alternative methods where interventions are allocated at the group level and outcomes are measured at the individual level. These designs are particularly useful for testing speech, language, and hearing care interventions in real-world settings where individual-randomized trials are not feasible.