Page 42 - Maximizing the efficacy of ankle foot orthoses in children with cerebral palsy

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Chapter II
Other outcomes
Other study outcome measures will include 1) the patient’s personal treatment goals, measured with Goal Attainment Scaling (GAS), 2) treatment adherence, assessed with a motivation diary and with the @monitor[54], 3) satisfaction with the FRO, as perceived by the patient and parents and 4) FRO stiffness, measured with BRUCE, which is a recently developed device for measuring mechanical AFO properties[55].
Statistical analysis
Subject population
Demographic variables and disease characteristics will be summarised using descrip- tive statistics. Furthermore, the means, medians, standard deviations and 95% confi- dence interval (CI) of primary and secondary outcome measures will be presented for all visits. In addition, correlations between parameters will be examined using correlation coefficients and graphical techniques.
Evaluation of FRO efficacy
Evaluation of the efficacy of a subject’s optimal FRO will be based on analyses of pre/post-intervention differences in primary and secondary outcome measures. The pre- intervention (control) condition will be for shoes-only. Mean data for these measure- ments (assessed at T1K2) will be compared to follow-up measurements (T2), using paired sample t-tests.
To identify working mechanisms, multivariate linear regression analyses will be applied to investigate which of the changes in gait biomechanics are associated with changes in walking energy cost (model 1) and daily activity (model 2). First, a univari- ate regression analysis (ANOVA) will be performed to determine which factors are sig- nificantly associated with changes in the biomechanics of gait (p≤0.1), followed by the analysis of significant factors (p≤.05) in a multivariate regression analysis model.
Identifying prognostic factors
Multivariate regression analysis will also be applied to investigate to what extent child characteristics and FRO stiffness represent determinants for success of FRO treat- ment, defined as decreased walking energy cost (model 1), improvement in daily activity (model 2) and positive GAS scores (model 3). Initially, a univariate regression analysis