Clinical prediction rules: the importance of the validation phase

Commentary On: Hicks K.E., Zhao Y., Fallah N, Rivers C, Noonan V, Plashkes T, Wai EK, Roffey DM, Tsai E, Paquet J, Attabib N, Marion T, Ahn H, Phan P. A simplified clinical prediction rule for prognosticating independent walking after spinal cord injury: a prospective study from a Canadian multicenter spinal cord injury registry. The Spine Journal. Article in press.