Using Machine Learning to Develop a Short-Form Measure Assessing 5 Functions in Patients With Stroke.

OBJECTIVE: This study aimed to develop and validate a machine learning-based short measure to assess 5 functions (the ML-5F) (activities of daily living [ADL], balance, upper extremity [UE] and lower extremity [LE] motor function, and mobility) in patients with stroke. DESIGN: Secondary data from a previous study. A follow-up study assessed patients with stroke using the Barthel Index (BI), Postural Assessment Scale for Stroke (PASS), and Stroke Rehabilitation Assessment of Movement (STREAM) at hospital admission and discharge. SETTING: A rehabilitation unit in a medical center. PARTICIPANTS: Patients (N=307) with stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The BI, PASS, and STREAM. RESULTS: A machine learning algorithm, Extreme Gradient Boosting, was used to select 15 items from the BI, PASS, and STREAM, and transformed the raw scores of the selected items into the scores of the ML-5F. The ML-5F demonstrated good concurrent validity (Pearson's r, 0.88-0.98) and responsiveness (standardized response mean, 0.28-1.01). CONCLUSIONS: The ML-5F comprises only 15 items but demonstrates sufficient concurrent validity and responsiveness to assess ADL, balance, UE and LE functions, and mobility in patients with stroke. The ML-5F shows great potential as an efficient outcome measure in clinical settings.

A functional generalized F-test for signal detection with applications to event-related potentials significance analysis.

Motivated by the analysis of complex dependent functional data such as event-related brain potentials (ERP), this paper considers a time-varying coefficient multivariate regression model with fixed-time covariates for testing global hypotheses about population mean curves. Based on a reduced-rank modeling of the time correlation of the stochastic process of pointwise test statistics, a functional generalized F-test is proposed and its asymptotic null distribution is derived. Our analytical results show that the proposed test is more powerful than functional analysis of variance testing methods and competing signal detection procedures for dependent data. Simulation studies confirm such power gain for data with patterns of dependence similar to those observed in ERPs. The new testing procedure is illustrated with an analysis of the ERP data from a study of neural correlates of impulse control.

Effects of luminance contrast and character size on reading speed.

Both luminance contrast and character size are critical factors affecting reading performance. Previous studies reported on the effect of luminance contrast on the reading-speed function, that is, the relationship between reading speed and character size. In particular, when contrast was reduced, the critical print size (CPS) was found to shift to a larger character size even though the maximum reading speed and function shape did not change [Japanese Journal of Ophthalmology 52(1) (2008) 44-47]. In the present study, the effect of luminance contrast on the reading function was quantitatively examined. Japanese phrases with a luminance contrast of 0.03-0.99 were prepared as stimuli. Observers with normal vision were asked to read aloud phrases with several character sizes. Then, the reading functions were obtained for each luminance contrast. CPS was found to increase as the luminance contrast decreased. The relationship between contrast and CPS was linear in log-log coordinates, that is, log-CPS increased as the log-contrast of the characters decreased. It was found that the contrast of the stimulus systematically affects the location of the reading function.

Latino-American Mothers' Perspectives on Feeding Their Young Children: A Qualitative Study.

OBJECTIVE: We explored the cultural beliefs that influence Latino-American mothers' feeding practices with their young children and the sources they referenced in making food choices for their children. METHOD: We conducted semistructured interviews with 12 Latino-American mothers focusing on their experiences of feeding their young children. Data analysis, based in grounded theory, consisted of interview transcription, content analysis, coding, and theme development. RESULTS: We identified four themes summarizing the mothers' feeding practices: (1) "Grandma knows best," (2) "I want my child(ren) to be healthy," (3) "always soup and always rice," and (4) "mealtime is family time." CONCLUSION: Occupational therapy practitioners need to obtain accurate information from families about feeding practices and to understand and interpret those practices in broader cultural contexts to design and implement targeted feeding intervention strategies that avoid stereotyping or misinterpreted information. To promote family-centered, meaningful interventions, practitioners must understand the cultural influences on feeding practices and be sensitive to mothers' needs.

Feeding Patterns and Parental Perceptions of Feeding Issues of Preterm Infants in the First 2 Years of Life.

We explored parental feeding practices, feeding issues during the first 2 yr of life, and the relationship between feeding issues and levels of maternal distress in preterm infants. Four hundred twenty mothers (239 with preterm infants, 181 with full-term infants) participated in the study. The Behavior-Based Feeding Questionnaire for Infants With Premature History and the Parenting Stress Index-Chinese Version were used as the two outcome measures. The results indicated that preterm infants had different feeding experiences compared with their full-term counterparts. They tended to start solid food later in life and had limited experiences in food variation. Parenting stress was prevalent in parents with preterm infants and was associated with the frequency of feeding issues, especially at later ages when supplementary foods were being introduced.

Teaching Theory in Occupational Therapy Using a Cooperative Learning: A Mixed-Methods Study.

Cooperative learning provides an important vehicle for active learning, as knowledge is socially constructed through interaction with others. This study investigated the effect of cooperative learning on occupational therapy (OT) theory knowledge attainment in professional-level OT students in a classroom environment. Using a pre- and post-test group design, 24 first-year, entry-level OT students participated while taking a theory course in their second semester of the program. Cooperative learning methods were implemented via in-class group assignments. The students were asked to complete two questionnaires regarding their attitudes toward group environments and their perception toward group learning before and after the semester. MANCOVA was used to examine changes in attitudes and perceived learning among groups. Students' summary sheets for each in-class assignment and course evaluations were collected for content analysis. Results indicated significant changes in students' attitude toward working in small groups regardless of their prior group experience.

Predicting neurodevelopmental outcomes at preschool age for children with very low birth weight.

The purpose of this study was to examine predictors of neurodevelopmental outcome in very low birth weight children without major impairment at 5 years of age, as well as to identify the contribution of early neurodevelopmental assessment to preterm children's later developmental outcomes. The participants in this study included 126 children who were prematurely born with very low birth weight. Outcomes of the childrens' later development were measured in tests that factored cognitive function, motor performance, and adaptive behavior. The results indicated that more than 50% of full-scale intelligence and 30% of both motor performance and adaptive behavior at the age of 5 can be explained by four predictors. The four predictors include preterm children's medical complications at birth, maternal education, early motor assessments, and cognitive assessments. Adding each test score obtained in early ages provides additional information to predict children's cognitive, motor, and adaptive behavior at 5 years of age. Manifold assessments conducted in multiple time periods strengthen the predictive values of later developmental outcomes. In addition, the findings of this study indicate that very low birth weight children tend to have lower adaptive behavior at 5 years old. With regard to our findings, we believe that having adaptive function is a reflection of a child's overall integrated abilities. Further study is warranted to increase understanding of this topic, as well as to be able to predict adaptive strengths and weakness and pinpoint limiting factors that may be useful for targeting behaviors in intervention.

Practice effects and test-re-test reliability of the Five Digit Test in patients with stroke over four serial assessments.

OBJECTIVES: To investigate practice effect and test-re-test reliability of the Five Digit Test (FDT) over four serial assessments in patients with stroke. DESIGN: Single-group repeated measures design. METHODS: Twenty-five patients with stroke were administered the FDT in four consecutive assessments every 2 weeks. The FDT contains four parts with five indices: 'basic measures of attention and processing speed', 'selective attention', 'alternating attention', 'ability of inhibition' and 'ability of switching'. RESULTS: The five indices of the FDT showed trivial-to-small practice effects (Cohen's d = 0.03-0.47) and moderate-to-excellent test-re-test reliability (intra-class correlation coefficient = 0.59-0.97). Practice effects of the five indices all appeared cumulative, but one index, 'basic measures of attention and processing speed', reached a plateau after the second assessment. The minimum and maximum values of the 90% confidence interval (CI) of reliable change index modified for practice (RCIp) for this index were [-17.6, 11.2]. CONCLUSIONS: One of five indices of the FDT reached a plateau, whose minimum and maximum values of the 90% CI RCIp are useful to determine whether the change in an individual's score is real. However, clinicians and researchers should be cautious when interpreting the test results of these four indices over repeated assessments.

Parenting stress in families with very low birth weight preterm infants in early infancy.

Taking care of a premature infant adds an extra burden to already stressed parents. Previous studies have shown that parental stress occurs during the initial hospitalization. However, there is little information on parental stress over time, and the few existing results are conflicting. In addition, many studies have focused on maternal stress but there is little information about a father's long-term adaptation to stress. The purpose of this study was to examine the degree and type of parenting stress in the families of very low birth weight (VLBW) preterm infants over the first two years of life. We compared parenting stress in families with preterm infants with control families, while also comparing the stress in mothers to that in fathers. Furthermore, we explored the relationship between parenting stress in the preterm group with identified factors that included the infant's age, medical complications, and parents' perceived feeding issues after they had been discharged from the hospital. This was an exploratory study with a cross sectional design. Participants included a total of 505 mothers from Tainan, Taiwan; 297 with preterm children (239 mothers, 58 fathers) and 208 with full-term children (181 mothers, 27 fathers). Assessments including the Parenting Stress Index, Neonatal Medical Index and Behavior-based Feeding Questionnaire were used to measure parental distress, infants' medical complications and parents' perceived feeding issues, respectively. Results of the study, though not statistically significant, indicated the presence of increased parenting stress in parents of preterm infants as compared to parents of full-term infants. 13.1% of mothers with preterm infants demonstrated total stress levels that warranted clinical intervention. We also found that mothers of preterm infants presented different parenting stress patterns than fathers of preterm infants. Fathers of preterm infants tended to have overall higher stress scores than mothers. On the other hand, mothers of preterm infants tended to report more health related difficulties, more depression, higher social isolation and role restriction, and less support from their spouses, than reported by fathers. Moreover, as time went on, parents with preterm infants continued to experience greater parenting stress than those with full-term infants. Understanding the experiences of parents with preterm children is important for health care providers while interviewing parents for information regarding their children and designing intervention programs to improve children's outcomes.

Latent classes in the developmental trajectories of infant handedness.

Handedness for acquiring objects was assessed monthly from 6 to 14 months in 328 infants (182 males). A group based trajectory model identified 3 latent groups with different developmental trajectories: those with an identifiable right preference (38%) or left preference (14%) and those without an identifiable preference (48%) but with a significant trend toward right-handedness. Each group exhibited significant quadratic trends: Those with a right preference increased to asymptote at about 10 months and began decreasing thereafter; those with a left preference increased to asymptote at about 11 months; those without a preference exhibited increasing right-hand use. Since adult handedness reflects different patterns of neural organization which relate to differences in psychological functioning, the observed differences in infant handedness development may relate to differences in the development of infant neurobehavioral organization and functioning. Several methods were used to explore the relation of latent classes to more conventional ways of classifying infant handedness. Classification into handedness groups according to either a monthly z-score or a combination of 4 or fewer months for a handedness index failed to provide reliable estimates of handedness identified by the trajectory analysis. If identified trajectories of handedness development relate to the development of the infant's neurobehavioral organization, researchers who assess infant handedness only once in order to relate it to cognitive, social and emotional functioning may risk misclassifying the handedness of as many as 37-45% of infants.

Validating and improving the reliability of the EORTC qlq-c30 using a multidimensional Rasch model.

OBJECTIVE: The reliability and validity of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) has not been examined while taking into account the correlation between subscales. The reliability of the EORTC QLQ-C30 subscales is modest, thus limiting their utility in both clinical and research settings. The purpose of this study was to validate the factor structure of multiple-item subscales of the EORTC QLQ-C30 and to improve their reliability by means of an item response analysis by using the multidimensional partial credit model. METHODS: A total of 2295 patients with complete data were used for the analysis. One- and nine-dimensional partial credit models were used to fit the data to validate the construct validity of the multiple-item subscales of the QLQ-C30. RESULTS: The model comparison showed that the nine-dimensional factor structure of multiple-item subscales was satisfactory. The multidimensional partial credit model fit data of the multiple-item subscales of the QLQ-C30 reasonably well. The estimated test reliabilities of each domain obtained from the multidimensional approach were higher than those obtained from the unidimensional approach. CONCLUSIONS: The constructs represented by the multiple-item subscales of the QLQ-C30 were validated. The improved reliability of the multiple-item subscales of the QLQ-C30 under the multidimensional approach can facilitate their applications in clinical and research settings.

Integrating health-related quality of life with sickness leave days for return-to-work assessment in traumatic limb injuries.

PURPOSE: A novel indicator called health-adjusted leave days (HALDs) is proposed. It integrates the opposite level of health-related quality of life (HRQoL) with the sick leave days (LDs) before return-to-work (RTW) to better measure the impact of injuries on occupational health. METHODS: A total of 1,167 limb injuries were consecutively recruited in a teaching hospital from January to December 2009. The number of LDs was calculated between the date of injury and the first episode of RTW. Each subject was repeatedly assessed with EuroQol instrument (EQ-5D) before RTW. The HRQoL index is defined as 1 minus the EQ-5D utility and re-scaled to 0-1 range to reflect the impact of injuries. The expected HALD of each group is calculated by integrating the product of the proportion of non-RTW function and the mean HRQoL index function over the days followed up to 2 years for the group. We compared the expected HALDs between subgroups according to various demographic characteristics and consequences of injury. RESULTS: Older and female workers tended to have longer LDs than men and younger workers, with an increase in percentage change of 16.0 or 139.5 %, respectively. After adjusting for HRQoL index, the percentages for HALDs were changed to 28.7 or 186.6 %, respectively. The percentages for the less-educated workers and blue collar workers were 185.7 and 155.8 %. The expected HALDs showed statistical significant differences in all subgroup analyses. CONCLUSION: We believed that the proposed HALD could better measure the impact of injuries and is potentially useful for the clinical decision and industrial policy-making with respect to the assessment of the importance of limb injury due to a worker's sick leaves.

Return to work and quality of life in workers with traumatic limb injuries: a 2-year repeated-measurements study.

OBJECTIVES: To assess the impact of return-to-work (RTW) status on health-related quality of life (HRQOL) over a 2-year period in workers with traumatic limb injuries and to elucidate factors that may contribute to the association of RTW with HRQOL. DESIGN: A 2-year repeated-measurements follow-up study using the generalized estimating equations approach for model fitting to account for within-subject correlations of HRQOL. SETTING: One teaching hospital. PARTICIPANTS: Injured patients (N=966, 61% men) with a mean age of 44.7 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The RTW status, HRQOL (assessed by the EuroQol five-dimensional questionnaire), and activity/participation were repeatedly surveyed at 2 weeks and 1, 3, 6, 12, 18, and 24 months after injury. A series of regression models was used to examine the associations between HRQOL and RTW, with sequential adjustment for explanatory variables such as personal and environmental factors, body structure and function, activity/participation, and postinjury period. RESULTS: Over a 2-year study period, 81.2% of the study participants had 1 or more RTW episodes; 38.2% of them successfully maintained their RTW status until the end. A significant positive association was found between RTW status and HRQOL. The association could largely be explained by the domains of activity/participation. A higher HRQOL was associated with a shorter length of hospital stay, better coping ability, frequent participation in activities of daily living, and a longer postinjury period. A reduced HRQOL, however, was observed for participants with more depressive symptoms. CONCLUSIONS: RTW showed a positive and independent influence on HRQOL in workers with limb injury. In addition, the activity/participation domains and the elapsed time since injury largely explained the association between RTW and HRQOL.

Assessing handwriting intervention effectiveness in elementary school students: a two-group controlled study.

This study examined the effectiveness of two approaches used in elementary schools to improve children's handwriting. Participants were 72 New York City public school students from the first and second grades. A nonequivalent pretest-posttest group design was used in which students engaged in handwriting activities using two approaches: intensive handwriting practice and visual-perceptual-motor activities. Handwriting speed, legibility, and visual-motor skills were examined after a 12-wk Handwriting Club using multivariate analysis of variance. The results showed that students in the intensive handwriting practice group demonstrated significant improvements in handwriting legibility compared with students in the visual-perceptual-motor activity group. No significant effects in handwriting speed and visual-motor skills were found between the students in intensive handwriting practice group and the students in visual-perceptual-motor activities group. The Handwriting Club model is a natural intervention that fits easily into existing school curriculums and can be an effective short-term intervention (response to intervention Tier II).

Aggressive and prosocial behavior: community violence, cognitive, and behavioral predictors among urban African American youth.

We use longitudinal multilevel modeling to test how exposure to community violence and cognitive and behavioral factors contribute to the development of aggressive and prosocial behaviors. Specifically, we examine predictors of self-, peer-, and teacher-reported aggressive and prosocial behavior among 266 urban, African American early adolescents. We examine lagged, within-person, between-person, and protective effects across 2 years. In general, results suggest that higher levels of violence exposure and aggressive beliefs are associated with more aggressive and less prosocial peer-reported behavior, whereas greater self-efficacy to resolve conflict peacefully is associated with less aggression across reporters and more teacher-reported prosocial behavior. Greater knowledge and violence prevention skills are associated with fewer aggressive and more prosocial teacher-reported behaviors. Results also suggest that greater self-efficacy and lower impulsivity have protective effects for youth reporting higher levels of exposure to community violence, in terms of teacher-reported aggressive behavior and peer-reported prosocial behavior. Differences among reporters and models are discussed, as well as implications for intervention.

A factor-adjusted multiple testing procedure for ERP data analysis.

Event-related potentials (ERPs) are now widely collected in psychological research to determine the time courses of mental events. When event-related potentials from treatment conditions are compared, often there is no a priori information on when or how long the differences should occur. Testing simultaneously for differences over the entire set of time points creates a serious multiple comparison problem in which the probability of false positive errors must be controlled, while maintaining reasonable power for correct detection. In this work, we extend the factor-adjusted multiple testing procedure developed by Friguet, Kloareg, and Causeur (Journal of the American Statistical Association, 104, 1406-1415, 2009) to manage the multiplicity problem in ERP data analysis and compare its performance with that of the Benjamini and Hochberg (Journal of the Royal Statistical Society B, 57, 289-300, 1995) false discovery rate procedure, using simulations. The proposed procedure outperformed the latter in detecting more truly significant time points, in addition to reducing the variability of the false discovery rate, suggesting that corrections for mass multiple testings of ERPs can be much improved by modeling the strong local temporal dependencies.

Development of a computerized adaptive testing system of the Fugl-Meyer motor scale in stroke patients.

OBJECTIVE: To develop a computerized adaptive testing system of the Fugl-Meyer motor scale (CAT-FM) to efficiently and reliably assess motor function in patients with stroke. DESIGN: First, a simulation study was used to develop and examine the psychometric properties of the CAT-FM. Second, a field study was employed to determine the administration efficiency of the CAT-FM. SETTING: One medical center and 1 teaching hospital. PARTICIPANTS: Patients' responses (n=301) were used for the simulation study; 49 patients participated in the field study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The 2 CAT-FM item banks (upper extremity and lower extremity) include 37 items from the original Fugl-Meyer scale. The reliability, validity, and responsiveness of the CAT-FM were determined by the simulation study. RESULTS: Two stopping rules (reliability ≥0.9 or an increase of reliability <.01 after testing an item) were used. The simulation study showed that the CAT-FM had high reliability (≥.93 for upper-extremity and lower-extremity subscales) and concurrent validity (Pearson r≥.91 for the upper-extremity and lower-extremity subscales and motor scale). The responsiveness was moderate (standardized response mean for the upper extremity=.67, lower extremity=.79, and motor=.77) for the 226 patients who completed both assessments at 14 and 90 days after stroke. The field study found that, on average, the time needed to administer the CAT-FM was 242 seconds with 4.7 items. CONCLUSIONS: The CAT-FM is an efficient, reliable, valid, and responsive clinical tool for assessing motor function in patients with stroke.

Trajectories and predictors of return to work after traumatic limb injury--a 2-year follow-up study.

OBJECTIVES: This study aims to explore the trajectories of return to work (RTW) and examine the predictors of different trajectories among workers following traumatic limb injury. METHODS: A total of 804 participants were recruited during hospital admission for a 2-year prospective study. The RTW outcome was repeatedly assessed at 1, 3, 6, 12, 18, and 24 months after the injury. A group-based trajectory model (GBTM) was employed to identify trajectories of RTW among the participants. Comparisons of group characteristics of different trajectories were performed based on a multinomial logistic regression. RESULTS: GBTM identified three distinct trajectories of RTW: (i) fast RTW consisted of workers with early and stable RTW status from the first month after the injury; (ii) average RTW consisted of workers who achieved and remained at a stable RTW status within 6 months; and (iii) slow RTW consisted of workers who had slow and unsustainable RTW status within the 2-year follow-up period. The estimated proportions were 21.5%, 50.7%, and 27.8%, respectively. Workers with slow and unsustainable RTW after injury were found to be older, married, less educated, employed as repair personnel/operators/laborers, seriously injured, and depressed; they were also found to feel more disturbance in daily life, have lower self-efficacy, and believe they experience a poorer quality of life. CONCLUSION: Following traumatic limb injury, individual workers showed three distinct RTW trajectories, each of which was associated with different categories of biopsychosocial factors. An understanding of how different factors contribute to increasing the likelihood of RTW for injured workers in each trajectory group should aid policy-making in worker-oriented vocational rehabilitation programs.

Comparison of virtual reality versus physical reality on movement characteristics of persons with Parkinson's disease: effects of moving targets.

OBJECTIVE: To compare the performance of reaching for stationary and moving targets in virtual reality (VR) and physical reality in persons with Parkinson's disease (PD). DESIGN: A repeated-measures design in which all participants reached in physical reality and VR under 5 conditions: 1 stationary ball condition and 4 conditions with the ball moving at different speeds. SETTING: University research laboratory. PARTICIPANTS: Persons with idiopathic PD (n=29) and age-matched controls (n=25). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Success rates and kinematics of arm movement (movement time, amplitude of peak velocity, and percentage of movement time for acceleration phase). RESULTS: In both VR and physical reality, the PD group had longer movement time (P<.001) and lower peak velocity (P<.001) than the controls when reaching for stationary balls. When moving targets were provided, the PD group improved more than the controls did in movement time (P<.001) and peak velocity (P<.001), and reached a performance level similar to that of the controls. Except for the fastest moving ball condition (0.5-s target viewing time), which elicited worse performance in VR than in physical reality, most cueing conditions in VR elicited performance generally similar to those in physical reality. CONCLUSIONS: Although slower than the controls when reaching for stationary balls, persons with PD increased movement speed in response to fast moving balls in both VR and physical reality. This suggests that with an appropriate choice of cueing speed, VR is a promising tool for providing visual motion stimuli to improve movement speed in persons with PD. More research on the long-term effect of this type of VR training program is needed.

Neuromotor outcomes in children with very low birth weight at 5 yrs of age.

OBJECTIVE: : The aim of this study was to assess a cohort of children with very low birth weight (VLBW) with premature history at the age of 5 yrs for the proportion of deficits in growth, motor, cognitive, and adaptive functions and to compare them with children with normal birth weight (>2500 g) in these areas. DESIGN: : This is a descriptive, exploratory study using a convenience sample. A cohort of 160 children with VLBW and 124 children with normal birth weight were examined. Standardized clinical and neuropsychologic assessments were administered. Correlation and multiple comparison procedures were used to analyze the relationships among all continuous outcome variables. RESULTS: : There is a significant difference in overall performance between the VLBW children and children with normal birth weight. Deficits in motor, cognitive, visual perception, visual-motor, and adaptive functions were more prominent when we further examined the VLBW children with motor problems. CONCLUSIONS: : The VLBW children performed more poorly at age 5 yrs than did their counterparts. This validates the need for early screening and regular follow-up of VLBW preterm children, particularly those who have motor problems.