Abstract
CONTEXT: Two-dimensional (2D) video-based analysis is often used by clinicians to examine the foot strike pattern (FSP) and step rate in runners. Reliability and validity of 2D video-based analysis have been questioned. OBJECTIVE: To synthesize the psychometric properties of 2D video-based analysis for assessing runners' FSP and step rate while running. DATA SOURCES: Medline/PubMed, Science Direct, Embase, EBSCOHost/CINAHL, and Scielo were searched from their inception to August 2018. STUDY SELECTION: Studies were included if (1) they were published in English, French, Portuguese or Spanish; (2) they reported at least 1 psychometric property (validity and/or reliability) of 2D video-based analysis to assess running kinematics; and (3) they assessed FSP or step rate during running. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 2. DATA EXTRACTION: Studies were screened for methodological (MacDermid checklist) and psychometric quality (COSMIN checklist) by 2 independent raters. RESULTS: Eight studies, with a total of 702 participants, were included. Seven studies evaluated the reliability of 2D video to assess FSP and found very good to excellent reliability (0.41 ≤ κ ≤ 1.00). Two studies reported excellent reliability for the calculation of step rate (0.75 ≤ intraclass correlation coefficient [ICC] ≤ 1.00). One study demonstrated excellent concurrent validity between 2D and 3D (gold standard) motion capture systems to determine FSP (Gwet agreement coefficient [AC] > 0.90; ICC > 0.90), and another study found excellent concurrent validity between 2D video and another device to calculate step rate (0.84 ≤ ICC ≤ 0.95). CONCLUSION: Strong evidence suggests that 2D video-based analysis is a reliable method for assessing FSP and quantifying step rate, regardless of the experience of the assessor. Limited evidence exists on the validity of 2D video-based analysis in determining FSP and calculating step rate during running.