I have been working on a dementia intervention study that assesses the impact of the intervention on people with dementia at three timepoints: T0, T1 and T2 with 3 months between each timeline (total intervention time = 6 months)
Due to COVID-19, timelines were not observed. For example, T0 - T1 ended up being ~ 10 months instead of 3 months. Then T1 - T2 ended up being 6 months.
Are you aware of any literature that discusses such delays with respect to intervention studies or dementia or other degenerative diseases?