A structural equation model of environmental correlates of adolescent obesity for age and gender groups.

BACKGROUND: The relationships between environmental correlates of adolescent obesity are complex and not yet well defined by current research, especially when considering age and gender. OBJECTIVE: The purpose of this study was to test a model of proximal (home) and distal (neighbourhood) environmental correlates of obesity for adolescent age and gender groups. METHODS: This was a descriptive, cross-sectional study, using the 2007 National Survey of Children's Health of 39 542 children ages 11-17 years. RESULTS: The model fit the data well for early adolescents (ages 11-14 years) (root mean square standard error of approximation [RMSEA] 0.040, 90% confidence interval [CI]: 0.039-0.041; comparative fit index [CFI] 0.947; Tucker-Lewis index [TLI] 0.929) and middle adolescents (ages 15-17 years) (RMSEA 0.037, 90% CI: 0.036-0.038; CFI 0.052; TLI 0.937). The model also fit the data well for boy adolescents (RMSEA 0.038, 90% CI: 0.037-0.039; CFI 0.951; TLI 0.935) and girl adolescents (RMSEA 0.038, 90% CI: 0.037-0.040; CFI 0.949; TLI 0.932). CONCLUSIONS: All models provide loadings of the environmental correlates of adolescent obesity for specific age and gender groups that can be used for early identification of risks and targeted interventions.

Comparison of two outcome measures for infants with cerebral palsy and infants with motor delays.

BACKGROUND AND PURPOSE: The purpose of this study was to compare the Gross Motor Function Measure (GMFM) and the Peabody Developmental Gross Motor Scale (PDMS-GM) as measures of change in infants with cerebr-al palsy (CP) and infants with motor delays. We hypothesized that mean change scores would be greater for the GMFM than for the PDMS-GM. SUBJECTS AND METHODS: Subjects were 42 infants with a mean adjusted age of 13.9 months (SD=6.1, range=4.2-24.2). Twenty-four infants had CP, and 18 infants had motor delays. The GMFM and the PDMS-GM were administered to the infants 3 times over a 6-month period. Raw scores were standardized for data analysis. Data were analyzed using a 3-factor repeated-measures analysis of variance. RESULTS: For the 6-month period, mean PDMS-GM age-equivalent scores increased 3.8 months and mean scaled scores increased 35 points for infants with motor delays compared with increased scores of 1.8 months and 13 points for infants with CP. Mean GMFM scores increased by 12.2% for infants with rmotor delays and by 4.2% for infants with CP. The diagnosis X time interaction was significant. Infants with motor delays had a greater change in motor development compared with the infants with CP. The hypothesis that the GMFM is more responsive to change than the PDMS-GM was not supported. CONCLUSION AND DISCUSSION: The findings suggest that the GMFM and the PDMS-GM are comparable in measuring change in infants with CP or motor delays. Implications for selection and use of either measure are discussed.

Validity of the Peabody Developmental Gross Motor Scale as an evaluative measure of infants receiving physical therapy.

BACKGROUND AND PURPOSE: The purpose of this study was to examine the validity of the Peabody Developmental Gross Motor Scale (PDMS-GM) as an evaluative measure of infants receiving physical therapy. SUBJECTS AND METHODS: Infants who attended an early intervention program (N = 124) were grouped by diagnosis: cerebral palsy, Down syndrome, hydrocephalus, preterm with developmental delay, full term with developmental delay, and other. The PDMS-GM was administered to each infant three times over a 6-month period by a therapist who did not provide treatment. RESULTS: Mean scaled scores and age-equivalent scores increased for each group. Individual change was examined using the reliable change index. The results indicated that the change in total raw score for 62% of the infants was greater than what could be attributed to measurement error. When minimal clinically important change was defined as 10 scaled score points, the index of responsiveness was equal to 0.5. This finding indicates that a sample size of 68 subjects per group would be needed when the PDMS-GM is used as an outcome measure in research. CONCLUSION AND DISCUSSION: The mean change scores for each group support the use of the PDMS-GM as an evaluative measure. For many infants, particularly infants with cerebral palsy, the PDMS-GM was not responsive to change over a 6-month period. The index of responsiveness suggests that the PDMS-GM should be used only as an outcome measure in large clinical trials. The PDMS-GM is not recommended for evaluating the direct effects of physical therapy but is recommended for providing a global measure of change in motor development as part of a multidimensional assessment.

Construct validity of the test of infant motor performance.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the construct validity of the Test of Infant Motor Performance (TIMP), specifically the test's sensitivity for assessing age-related changes in motor skill and correlation with risk for developmental abnormality. SUBJECTS: Subjects were 137 term and preterm infants stratified by postconceptional age, medical complications score on the Problem-Oriented Perinatal Risk Assessment System, and ethnicity and race (non-Latino Caucasian, African-American, and Latino). METHODS: Subjects were tested on the TIMP at ages ranging from 32 weeks postconceptional age to 3.5 months past term-equivalent age. Scores (Rasch logit ability measures) were correlated with postconceptional age. A multiple regression analysis was used to assess the contributions of age, risk, and ethnicity to the variance in TIMP scores. RESULTS: The correlation between postconceptional age and TIMP performance measures was .83. Risk and age together explained 72% of the variance in TIMP performance (R = .85, P < .00001). No differences related to ethnicity were found. CONCLUSION AND DISCUSSION: The TIMP has validity for assessing age-related development of functional motor skills in young infants and is sensitive to risk for poor developmental outcome.