Machine Learning to Quantify Physical Activity in Children with Cerebral Palsy: Comparison of Group, Group-Personalized, and Fully-Personalized Activity Classification Models.

Pattern recognition methodologies, such as those utilizing machine learning (ML) approaches, have the potential to improve the accuracy and versatility of accelerometer-based assessments of physical activity (PA). Children with cerebral palsy (CP) exhibit significant heterogeneity in relation to impairment and activity limitations; however, studies conducted to date have implemented "one-size fits all" group (G) models. Group-personalized (GP) models specific to the Gross Motor Function Classification (GMFCS) level and fully-personalized (FP) models trained on individual data may provide more accurate assessments of PA; however, these approaches have not been investigated in children with CP. In this study, 38 children classified at GMFCS I to III completed laboratory trials and a simulated free-living protocol while wearing an ActiGraph GT3X+ on the wrist, hip, and ankle. Activities were classified as sedentary, standing utilitarian movements, or walking. In the cross-validation, FP random forest classifiers (99.0-99.3%) exhibited a significantly higher accuracy than G (80.9-94.7%) and GP classifiers (78.7-94.1%), with the largest differential observed in children at GMFCS III. When evaluated under free-living conditions, all model types exhibited significant declines in accuracy, with FP models outperforming G and GP models in GMFCS levels I and II, but not III. Future studies should evaluate the comparative accuracy of personalized models trained on free-living accelerometer data.

Validity of the OMNI rating of perceived exertion scale for children and adolescents with cerebral palsy.

AIM: This study evaluated the validity of the OMNI Walk/Run Rating of Perceived Exertion (OMNI-RPE) scores with heart rate and oxygen consumption (VO2) for children and adolescents with cerebral palsy (CP). METHOD: Children and adolescents with CP, aged 6 to 18 years and Gross Motor Function Classification System (GMFCS) levels I to III completed a physical activity protocol with seven trials ranging in intensity from sedentary to moderate-to-vigorous. VO2 and heart rate were recorded during the physical activity trials using a portable indirect calorimeter and heart rate monitor. Participants reported OMNI-RPE scores for each trial. Concurrent validity was assessed by calculating the average within-subject correlation between OMNI-RPE ratings and the two physiological indices. RESULTS: For the correlational analyses, 48 participants (22 males, 26 females; age 12y 6mo, SD 3y 4mo) had valid bivariate data for VO2 and OMNI-RPE, while 40 participants (21 males, 19 females; age 12y 5mo, SD 2y 9mo) had valid bivariate data for heart rate and OMNI-RPE. VO2 (r=0.80; 95% CI 0.66-0.88) and heart rate (r=0.83; 95% CI 0.70-0.91) were moderately to highly correlated to OMNI-RPE scores. No difference was found for the correlation of physiological data and OMNI-RPE scores across the three GMFCS levels. The OMNI-RPE scores increased significantly in a dose-response manner (F(6,258) =116.1, p<0.001) as exercise intensity increased from sedentary to moderate-to-vigorous. INTERPRETATION: OMNI-RPE is a clinically feasible option to monitor exercise intensity in ambulatory children and adolescents with CP.

Systematic review of the clinimetric properties of laboratory- and field-based aerobic and anaerobic fitness measures in children with cerebral palsy.

OBJECTIVE: To systematically evaluate the level of evidence of the clinimetric properties of measures of aerobic and anaerobic capacity used for children with cerebral palsy (CP). DATA SOURCES: A systematic search of databases PubMed, Embase, SPORTDiscus, and PsycINFO through April 2011 was performed. STUDY SELECTION: Two independent raters identified and examined studies that reported laboratory- or field-based measures of maximal aerobic or anaerobic capacity in children with CP aged 5 to 14 years. DATA EXTRACTION: The COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) checklist was used by 2 independent raters to evaluate the methodologic quality of the included clinimetric studies and to identify measures used in these studies. DATA SYNTHESIS: Twenty-four studies that used a maximal aerobic or anaerobic capacity measure were identified. Five studies reported clinimetric properties for 5 measures (2 aerobic and 3 anaerobic measures). Methodologic quality was excellent in 3 studies, showing good validity and reliability of field-based aerobic (Shuttle Run Test) and anaerobic (Muscle Power Sprint Test) measures. The studies on laboratory-based measures were rated fair, mainly because of inadequate statistics. The level of evidence was strong for good validity and reliability of the field-based tests. The level of evidence was unknown for validity and low to moderate for good reliability of laboratory-based tests. CONCLUSIONS: There is a paucity of research on the clinimetric properties of measurement instruments to assess aerobic and anaerobic capacity for children with CP. Further clinimetric studies of laboratory-based measures in children with CP at all Gross Motor Function Classification System (GMFCS) levels, and clinimetric studies of field-based measures in children who are classified as GMFCS levels III to V are required.

Policy brief: adaptive cycling equipment for individuals with neurodevelopmental disabilities as durable medical equipment.

- Durable medical equipment (DME) policies require that the equipment be medically necessary; however, adaptive cycling equipment (bicycles and tricycles) are usually not deemed medically necessary. - Individuals with neurodevelopmental disabilities (NDD) are at high risk for secondary conditions, both physical and mental, that can be mitigated by increasing physical activity. - Significant financial costs are associated with the management of secondary conditions. - Adaptive cycling can provide improved physical health of individuals with NDD potentially reducing costs of comorbidities. - Expanding DME policies to include adaptive cycling equipment for qualifying individuals with NDD can increase access to equipment. - Regulations to ensure eligibility, proper fitting, prescription, and training can optimize health and wellbeing. - Programs for recycling or repurposing of equipment are warranted to optimize resources.

Perspectives of therapist's role in care coordination between medical and early intervention services.

This study explored perspectives of therapist's role in care coordination between early intervention (EI) and medical services, and identified strategies for improving service delivery. Fifty adults participated in one of six focus groups. Participants included parents, pediatricians, and therapists working in hospital and EI programs. Structured guiding questions were used to obtain participants' perceptions. Transcript analysis included open code identification, axial code grouping, and constant comparative methods. The researchers established inter-rater reliability (kappa = 0.85) in the coding scheme before data analysis. The themes identified included information exchange, communication among parents and therapists, approaches toward child and family care, supporting social and emotional needs, perceptions of therapists' roles, and understanding service delivery systems to improve care coordination. Participants recommended training for therapy service providers and pediatricians in the areas of child development, team building, and service systems. Family-centered strategies emphasizing systems of care are recommended to improve therapists' role in care coordination.

Parents' perspectives on access to rehabilitation services for their children with special healthcare needs.

PURPOSE: This study examined parents' (caregivers') perspectives on problems related to access to therapy services for their children with special healthcare needs (CSHCN) as predicted by child, family, and health insurance characteristics. METHODS: Secondary data analysis was conducted using the Family Partners Project database. A subsample of 1027 parents of CSHCN who received rehabilitation services in the year before the study were the participants. RESULTS: Child, family, and insurance characteristics explained 19.1% of problems related to access to rehabilitation services with family characteristics being the strongest predictor (10.8%). Odds ratios are reported for these characteristics. CONCLUSION: Family financial hardship, the child's age, and managed care practices in health insurance plans may be the primary factors contributing to problems related to access to therapy services for CSHCN. Therapists may need a better understanding of family challenges with access to services to be more effective advocates.

Calculating Heart Rate Variability from ECG Data from Youth with Cerebral Palsy During Active Video Game Sessions.

The aim of this study was to generate a method for calculating heart rate variability (HRV) from electrocardiogram (ECG) waveforms. The waveforms were recorded by a HR monitor that participants (youth with cerebral palsy (CP)) wore during active video game (AVG) sessions. The AVG sessions were designed to promote physical activity and fitness (aerobic performance) in participants. The goal was to evaluate the feasibility of AVGs as a physical therapy (PT) intervention strategy. The maximum HR (mHR) was determined for each participant and the Target Heart Rate Zone (THRZ) was calculated for each of three exercise phases in the 20 min AVG session: (warm-up at 40-60% mHR, conditioning at 60-80% mHR, and cool down at 40-60% mHR). Each participant played three 20 min games during the AVG session. All games were played while sitting on a bench because many youth with CP cannot stand for extended periods of time. Each game condition differed with participants using hand icons only, hand and feet icons together or feet icons only to collect objects. The objective of the game (called KOLLECT) is to collect objects to gain points and avoid hazards to not lose points. Hazards were used in the warm-up and cool down phases only to promote slower, controlled movement to maintain HR in the target heart rate zone (THRZ). There were no hazards in the conditioning phase to promote higher levels and more intense physical activity. Analytic methods were used to generate HRV (selected time-domain and frequency-domain measures) from ECG data to examine aerobic workload. Recent applications of HRV indicate that short-term measurements (5 min bouts) are appropriate and that HRV biofeedback may help improve symptoms and the quality of life in a variety of health conditions. Although HR is a well-accepted clinical measure to examine aerobic performance and intensity in PT interventions, HRV may provide information of the autonomic system functions, recovery and adaptation during AVG sessions.

Utilization of Physical Therapy Services During Transition for Young People With Cerebral Palsy: A Call for Improved Care Into Adulthood.

Background: Many young adults with cerebral palsy (CP) face limited participation in activities, including employment and independent living. Physical therapy during the transition period can help to support participation through promotion of self-care, ambulation, and functional mobility. Thus, ensuring appropriate access to physical therapy services for young people who can benefit from them before, during, and after transition is imperative. Objective: The objective of this study was to identify factors contributing to the utilization of physical therapy services for youth with CP both during and after secondary school. Design: The design was a deidentified secondary analysis of the National Longitudinal Transition Study 2 (NLTS2). Methods: Multivariate regression models were run to examine demographic and disability characteristics influencing utilization of physical therapy services for youth with CP both during and after secondary school. Results: The total weighted population sample included 35,290 young people with CP. When all youth were in secondary school, 59.4% of the youth utilized physical therapy services; however, once all youth were out of school, only 33.7% of them were reported to have utilized physical therapy since leaving secondary school. For young people with difficulties accessing general disability support services, demographic characteristics, including sex, race, income, and parent education status, influenced use of physical therapy services in addition to disability characteristics. Limitations: This population sample included only young people in special education with Individual Education Plans (IEPs) and may not generalize to young people with CP in general education settings. Conclusions: Frequency of physical therapy services decreases drastically once young adults with CP leave secondary school. Future work should examine this trend in more depth to identify therapy intervention strategies to optimize participation in young adult life for persons with CP.

Decision Trees for Detection of Activity Intensity in Youth with Cerebral Palsy.

PURPOSE: To develop and test decision tree (DT) models to classify physical activity (PA) intensity from accelerometer output and Gross Motor Function Classification System (GMFCS) classification level in ambulatory youth with cerebral palsy (CP) and compare the classification accuracy of the new DT models to that achieved by previously published cut points for youth with CP. METHODS: Youth with CP (GMFCS levels I-III) (N = 51) completed seven activity trials with increasing PA intensity while wearing a portable metabolic system and ActiGraph GT3X accelerometers. DT models were used to identify vertical axis (VA) and vector magnitude (VM) count thresholds corresponding to sedentary (SED) (<1.5 METs), light-intensity PA (LPA) (≥1.5 and <3 METs) and moderate-to-vigorous PA (MVPA) (≥3 METs). Models were trained and cross-validated using the "rpart" and "caret" packages within R. RESULTS: For the VA (VA_DT) and VM DT (VM_DT), a single threshold differentiated LPA from SED, whereas the threshold for differentiating MVPA from LPA decreased as the level of impairment increased. The average cross-validation accuracies for the VC_DT were 81.1%, 76.7%, and 82.9% for GMFCS levels I, II, and III. The corresponding cross-validation accuracies for the VM_DT were 80.5%, 75.6%, and 84.2%. Within each GMFCS level, the DT models achieved better PA intensity recognition than previously published cut points. The accuracy differential was greatest among GMFCS level III participants, in whom the previously published cut points misclassified 40% of the MVPA activity trials. CONCLUSIONS: The GMFCS-specific cut points provide more accurate assessments of MVPA levels in youth with CP across the full spectrum of ambulatory ability.

Reliability and Validity of Objective Measures of Physical Activity in Youth With Cerebral Palsy Who Are Ambulatory.

BACKGROUND: Physical therapy for youth with cerebral palsy (CP) who are ambulatory includes interventions to increase functional mobility and participation in physical activity (PA). Thus, reliable and valid measures are needed to document PA in youth with CP. OBJECTIVE: The purpose of this study was to evaluate the inter-instrument reliability and concurrent validity of 3 accelerometer-based motion sensors with indirect calorimetry as the criterion for measuring PA intensity in youth with CP. METHODS: Fifty-seven youth with CP (mean age=12.5 years, SD=3.3; 51% female; 49.1% with spastic hemiplegia) participated. Inclusion criteria were: aged 6 to 20 years, ambulatory, Gross Motor Function Classification System (GMFCS) levels I through III, able to follow directions, and able to complete the full PA protocol. Protocol activities included standardized activity trials with increasing PA intensity (resting, writing, household chores, active video games, and walking at 3 self-selected speeds), as measured by weight-relative oxygen uptake (in mL/kg/min). During each trial, participants wore bilateral accelerometers on the upper arms, waist/hip, and ankle and a portable indirect calorimeter. Intraclass coefficient correlations (ICCs) were calculated to evaluate inter-instrument reliability (left-to-right accelerometer placement). Spearman correlations were used to examine concurrent validity between accelerometer output (activity and step counts) and indirect calorimetry. Friedman analyses of variance with post hoc pair-wise analyses were conducted to examine the validity of accelerometers to discriminate PA intensity across activity trials. RESULTS: All accelerometers exhibited excellent inter-instrument reliability (ICC=.94-.99) and good concurrent validity (rho=.70-.85). All accelerometers discriminated PA intensity across most activity trials. LIMITATIONS: This PA protocol consisted of controlled activity trials. CONCLUSIONS: Accelerometers provide valid and reliable measures of PA intensity among youth with CP.

Decision making for physical therapy service delivery in schools: a nationwide survey of pediatric physical therapists.

BACKGROUND AND PURPOSE: A nationwide survey was conducted to explore decision making among school-based physical therapists and to examine recommendations regarding the models, contexts, frequency, and intensity of physical therapy service delivery. Factors that the therapists considered important in making clinical decisions also were examined. SUBJECTS AND METHODS: A survey instrument using a clinical case format was sent to all members of the American Physical Therapy Association's Section on Pediatrics who identified themselves as school-based therapists (N=1,154); 626 respondents, from all 50 states, completed the survey. Four case descriptions were presented in the survey: 2 preschool girls with developmental delay (1 with and 1 without cognitive impairment) and a boy with cerebral palsy (at 6 and 12 years of age). RESULTS: Individual direct services were recommended by 52% to 55% of the respondents for both 4-year-old girls and for the boy at 12 years of age; 92% of the respondents recommended them for the boy at 6 years of age. The most prevalent choice (48%-73%) for the context of service delivery (location or environment) was a combination of integrated and isolated contexts. For those respondents who selected direct services (individual or group, or both), the mean recommended monthly frequency for the boy at 6 years of age (5.8) was more than twice that for the boy at 12 years of age (2.4). The mean suggested direct frequency for the girl with cognitive impairment (4.5) was greater than that for the girl without cognitive impairment (4). The students' functional levels were considered very to extremely important in decision making by 87% to 90% of the respondents. DISCUSSION AND CONCLUSION: Survey responses were relatively consistent with current literature regarding school practice and principles of motor learning. Recommendations varied for each case, regarding the models, contexts, frequency, and intensity of physical therapy service delivery.

Clinical findings and resource use of infants and toddlers dependent on oxygen and ventilators.

Medical records were reviewed to describe characteristics, report clinical and resource measures, and determine if differences exist between the diagnostic groups of prematurity and multiple congenital anomalies/neurologic conditions for initial admissions of 37 infants and toddlers to an inpatient pulmonary rehabilitation program. More than 75% of the children had a tracheostomy at admission and discharge. Forty-six percent of the sample was admitted requiring only oxygen, whereas 51% were discharged requiring only oxygen and not mechanical ventilation. Thirty percent of the children weaned to a less invasive mode of ventilation while just under half of the children were discharged home. Between-group comparisons indicated statistically significant differences for nutritional support at discharge (p < or = 0.05) and discharge disposition (p = 0.04). Complete weaning of oxygen or ventilator support during an initial inpatient pulmonary rehabilitation admission occurred less frequently than weaning to a less invasive mode of ventilation. This is an important consideration for referring children to rehabilitation programs, for clinical program improvement activities, and for setting realistic expectations for referral sources, patients and families, clinical staff, and payers. Further study is recommended using clinical data in program planning, in program improvements, and for setting outcome expectations for infants and toddlers dependent on pulmonary technology.

Measuring reliability and validity of the ActiGraph GT3X accelerometer for children with cerebral palsy: a feasibility study.

PURPOSE: The purposes of this study were to: 1) establish inter-instrument reliability between left and right hip accelerometer placement; 2) examine procedural reliability of a walking protocol used to measure physical activity (PA); and 3) confirm concurrent validity of accelerometers in measuring PA intensity as compared to the gold standard of oxygen consumption measured by indirect calorimetry. METHODS: Eight children (mean age: 11.9; SD: 3.2, 75% male) with CP (GMFCS levels I-III) wore ActiGraph GT3X accelerometers on each hip and the Cosmed K4b^{2} portable indirect calorimeter during two measurement sessions in which they performed the six minute walk test (6MWT) at three self-selected speeds (comfortable/slow, brisk, fast). Oxygen consumption (VO2) and accelerometer step and activity count data were recorded. RESULTS: Inter-instrument reliability of ActiGraph GT3X accelerometers placed on left and right hips was excellent (ICC=0.96-0.99, CI_{95}: 0.81-0.99). Reproducibility of the protocol was good/excellent (ICC=0.75-0.95, CI_{95}: 0.75-0.98). Concurrent validity of accelerometer count data and VO2 was fair/good (rho=0.67, p< 0.001). The correlation between step count and VO2 was not significant (rho=0.29, p=0.2). CONCLUSION: This preliminary research suggests that ActiGraph GT3X accelerometers are reliable and valid devices to monitor PA during walking in children with CP and may be appropriate in rehabilitation research and clinical practice. ActiGraph GTX3 step counts were not valid for this sample and further research is warranted.

Aquatic aerobic exercise for children with cerebral palsy: a pilot intervention study.

PURPOSE: The primary purpose of this pilot study was to evaluate the effectiveness of a14-week aquatic exercise program on gross motor function and walking endurance in children with cerebral palsy (CP). The secondary purpose was to evaluate changes in functional strength, aerobic capacity and balance. METHOD: A prospective time series group design consisting of four measurement sessions (two baseline, one post intervention, and 1-month follow-up) was used. Eight ambulatory children ages 6-15 years with CP and classified at Gross Motor Function Classification System Level I or Level III participated in an aquatic aerobic exercise program. RESULTS: Significant improvements were observed for the primary outcomes of gross motor function and walking endurance. No significant differences between any of the secondary measures were observed, although all of the measures demonstrated trends of improvement after intervention. CONCLUSION: Ambulatory children with CP may improve their gross motor skills and walking endurance after an aquatic exercise program held twice per week for 14 weeks, utilizing moderate-to-vigorous exercise intensity and consisting of functional activities.

Factors influencing physical activity in children and youth with special health care needs: a pilot study.

Background. Evidence suggests that children and youth with special health care needs (CYSHCN) have decreased physical activity compared to peers. This study describes weight status and physical activity in CYSHCN and identifies factors associated with physical activity and community resources to promote physical activity. Methods. Parents (n = 21) and CYSHCN (n = 23) were recruited from a pediatric clinic. The most prevalent diagnoses were autism (n = 7, 30%) and cerebral palsy (n = 3, 13%). Interviews were conducted with parents for information on physical activity and community resources. Children's height and weight were measured to calculate body mass index (BMI). Results. The majority of CYSHCN (n = 13, 59%) were obese. CYSHCN did not meet recommended levels of 60 minutes of daily physical activity and engaged in more screen time than recommended. More children with cognitive/behavioral/emotional diagnoses were obese compared to children with physical/medical diagnoses. A majority of parents (n = 16, 73%) indicated their CYSHCN need more supervision to participate in physical activity in community programs. Conclusion. The majority of CYSHCN in this study were obese and sedentary. Resources to promote physical activity are needed for this population.