Postural Control Performance on the Functional Reach Test: Validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) Criteria.

OBJECTIVE: Evaluate the validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) clinical criteria for the Functional Reach Test (FRT) forward and lateral with laboratory measures of postural control in children with cerebral palsy (CP). DESIGN: Psychometric study of face, concurrent, and content validity. SETTING: Clinical laboratory. PARTICIPANTS: Children (N=58) aged 7-18 years (ambulant CP n=17, typically developing [TD] n=41). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Stability limits in standing were assessed using the Kids-BESTest items for FRT forwards (FRTFORWARD), FRT lateral preferred (FRTLATERAL(P)), and FRT lateral nonpreferred (FRTLATERAL(NP)). Force platforms and kinematic markers were used to collect information on center of pressure (CoP) and joint movement during reach. Analyses included face validity (Kids-BESTest scores compared between CP and TD groups), concurrent validity (agreement between Kids-BESTest scores and digitally derived scores), and content validity (relations between Kids-BESTest scores with kinematic and CoP data). RESULTS: Face validity of Kids-BESTest criteria was demonstrated with lower scores for CP compared to TD groups for FRTFORWARD (P<.001) and FRTLATERAL(NP) (P=.03) and equal scores for FRTLATERAL(P) (P=.12). For concurrent validity, agreement between Kids-BESTest scores and digitally derived scores was good to excellent for FRTLATERAL(both P/NP) (88%-100%) and good for FRTFORWARD (86%-88%) for both groups. For content validity, the CP group Kids-BESTest scores were correlated with CoP-RangeFORWARD during FRTFORWARD (ρ=0.68) and CoP-RangeLATERAL during FRTLATERAL(NP) (ρ=0.57). For kinematic data, correlations were moderate-high between Kids-BESTest scores and range of hip flexion (ρ=0.51) and ankle plantar flexion (ρ=0.75) during FRTFORWARD, and trunk lateral flexion (ρ=0.66) during FRTLATERAL(NP). CONCLUSION: The FRTFORWARD demonstrated face, concurrent, and content validity. The FRTLATERAL(P/NP) demonstrated concurrent validity, but partial face and content validity. To improve validity of Kids-BESTest FRT criteria, additional descriptors have been added under the scoring criteria to enable clinicians to quantify observed reach strategies.

Evaluating validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) Clinical Test of Sensory Integration of Balance (CTSIB) criteria to categorise stance postural control of ambulant children with CP.

PURPOSE: Evaluate the validity of the Clinical Test of Sensory Integration of Balance (CTSIB) scored using Kids-Balance Evaluation Systems Test (Kids-BESTest) criteria compared to laboratory measures of postural control. METHOD: Participants were 58 children, 7-18 years, 17 with ambulant cerebral palsy (CP) (GMFCS I-II), and 41 typically developing (TD). Postural control in standing was assessed using CTSIB items firm and foam surfaces, eyes open (EO) then closed (EC). Face validity was evaluated comparing clinical Kids-BESTest scores between groups. Correlating force plate centre-of-pressure (CoP) data and clinical scores allowed evaluation of concurrent and content validity. RESULTS: Face validity: TD children scored higher for all CTSIB conditions when compared to children with CP. Concurrent validity: the agreement between clinical and CoP derived scores was poor to excellent (Firm-EO = 76%, Firm-EC = 76%, Foam-EO = 59%, Foam-EC = 94%). Clinical scores of "2-unstable" and "3-stable" were not distinguished reliably by force plate measures. Content validity: significant correlations were found between clinical scores and CoP data for the two intermediate conditions (Firm-EC: rs -0.40 to -0.72; Foam-EO: rs -0.12 to -0.50), but not the easier (Firm-EO: rs -0.41 to -0.36) or harder conditions (Foam-EC: rs -0.25 to -0.27). CONCLUSION: Face validity of Kids-BESTest CTSIB criteria was supported. Content and concurrent validity were partially supported. Improved Kids-BESTest scoring terms were recommended to describe postural characteristics of "2-unstable."IMPLICATIONS FOR REHABILITATIONFace validity of the Kids-BESTest criteria for the CTSIB was confirmed.The Kids-BESTest criteria for the CTSIB can identify children with atypical postural control.Concurrent validity and content validity were partially supported, since children with CP resorted to a range of different balance strategies when "unstable."To improve CTSIB Kids-BESTest criteria, new terms were recommended to better describe postural characteristics of "2-unstable."