A 3-group randomized controlled trial comparing a positioning protocol, the MPS, and a combination of both would further clarify the effect of each intervention.
Blanchard, Y. & Lammers, K.M. (2018). Commentary on "Use of a midliner positioning system for prevention of dolichocephaly in preterm infants". Pediatric Physical Therapy, 30(2), 134. doi: 10.1097/PEP.0000000000000496