Two-dimensional (2D) video is often used to evaluate running gait. Cost effective and clinically applicable methods have not been validated. The objective of this study was to evaluate the concurrent validity and agreement of methods used to determine step rate (SR) and foot strike pattern (FSP) during running using 2D video. We observed excellent agreement assessing SR from a 30 Hertz (Hz) video for 10 seconds (s) and multiplying it by 6. We observed excellent interrater agreement assessing FSP for 10s at 240 Hz. These 10s methods for assessing running may be used to inform clinical decision making when evaluating running gait. Key point's Two-dimensional video assessment at 30 Hz demonstrated high intra-and interrater reliability for detecting step rate; the 10-second method is valid and reliable for detecting step rate when compared to the 60-second method; Detecting foot strike using a 2-point scale is more reliable at 240Hz rather than 30Hz.

a girl, aged 12, was observed one year ago to be walking peculiarly. Inability to use left band properly noticed about same time. Both disabilities have increased gradually since. Nothing of interest in past history. Family History.-Father suicide. Otherwise clear. Present Condition.-Cranial nerves: slight weakness of left lower face otherwise normal. Tone and deep reflexes increased in left upper limb. Latter retarded in development-arm, forearm and hand being smaller than on right side (about 1 in. of total shortening). Fine tremor of both hands. Abdominal reflexes present and equal. Tone and deep reflexes increased in left lower limb. Plantar reflex flexor. Slight weakness of extensor muscles of left foot. No tremor. There is half an inch shortening of left leg. Left side of face is smaller than right. Navus in right fronto-temporal region. No sensory changes; sphincters normal. Gait.-Sways to left as if tending to fall in that direction, and suggests that of a slight left hemiplegia.