Validity and Reliability of Kinetic Step Box on vertical Ground Reaction Forces Measurement

Kinetic Step Box was developed with the purpose for analyzing body movements by detecting vertical Ground Reaction Forces. The objective is to test on validity and reliability of vertical Ground Reaction Forces measurement from Kinetic Step Box compared with Standard Force Plate. 13 females and 7 males performed sitting to standing posture on Kinetic Step Box and Standard Force Plate for 3 sets of 5 times (each set was measured by each rater). All data were collected on the frequency at 100 Hz/sec for 2 seconds. The validity of mean vertical Ground Reaction Forces between Standard Force Plate and Kinetic Step Box was tested by Pearson’s Correlation Coefficient. Intra-rater reliability of Standard Force Plate and Kinetic Step Box were calculated by using intraclass correlation coefficient (3,1) and for inter-rater reliability by using intraclass correlation coefficient 
(3, 3). Standard Force Plate and Kinetic Step Box had the validity of mean vertical Ground Reaction Forces at the very high level with r = 0.996. The intra-rater reliability of Standard Force Plate and Kinetic Step Box were at the very high level with r = 1.000 and 1.000.  The inter-rater reliability of Standard Force Plate and Kinetic Step Box were at the very high level with r = 1.000 and 1.000. Kinetic Step Box has vertical Ground Reaction Forces measuring capacity similar of Standard Force Plate. Kinetic Step Box can be an alternative of Standard Force Plate for simple motion measurement. Kinetic Step Box is low cost, real-time display, and portability.