From: Matching actual treatment with patient administration-route-preference improves analgesic response among acute low back pain patients—a randomized prospective trial
Administration route preference
PO (n = 21)
IM (n = 17)
Actual administration method
PO (n = 13)
A (prefer PO, received PO, n = 9)
B (prefer IM, received PO, n = 4)
IM (n = 25)
C (prefer PO, received IM, n = 12)
D (prefer IM, received IM, n = 13)