I am nvestigating the effect of an intervention treatment on a group of samples over 5 time points (a period of 2 months in total) For example, Subject 1 - Timepoint 1 (Dose 1) ,2 (Dose 1) ,3 (Dose 2),4 (Dose 3),5 (No dose) Subject 2 - Timepoint 1 (Dose 1) ,2 (Dose 1) ,3 (Dose 2),4 (Dose 3),5 (No dose) etc. The dependent variable measured is a protein concentration, so it is a continuous variable. At timepoints 3 and 4, the dosage of the intervention was increased. To compare the protein concentration of the samples between all 5 timepoints, which test would be more suitable? I am personally leaning towards Friedman's test over Kruskal-Wallis, but would like some confirmation.