Sample size and study design
This study suggests that longer daily dosage may not necessarily be more effective. The sample size calculations (To reduce the burden of the study, most daily treatments could be carried out at home with attendance for pre- and posttreatment assessments weekly. To examine potential long-term effects, it is suggested that participants are followed up for a longer period (e.g., weekly for 1 month), although the data from this study do not inform the optimum follow-up period.