Deductive automated pollen classification in environmental samples via exploratory deep learning and imaging flow cytometry.

Pollen and tracheophyte spores are ubiquitous environmental indicators at local and global scales. Palynology is typically performed manually by microscopic analysis; a specialised and time-consuming task limited in taxonomical precision and sampling frequency, therefore restricting data quality used to inform climate change and pollen forecasting models. We build on the growing work using AI (artificial intelligence) for automated pollen classification to design a flexible network that can deal with the uncertainty of broad-scale environmental applications. We combined imaging flow cytometry with Guided Deep Learning to identify and accurately categorise pollen in environmental samples; here, pollen grains captured within c. 5500 Cal yr BP old lake sediments. Our network discriminates not only pollen included in training libraries to the species level but, depending on the sample, can classify previously unseen pollen to the likely phylogenetic order, family and even genus. Our approach offers valuable insights into the development of a widely transferable, rapid and accurate exploratory tool for pollen classification in 'real-world' environmental samples with improved accuracy over pure deep learning techniques. This work has the potential to revolutionise many aspects of palynology, allowing a more detailed spatial and temporal understanding of pollen in the environment with improved taxonomical resolution.

Ability of PROMIS Pediatric Measures to Detect Change in Children With Cerebral Palsy Undergoing Musculoskeletal Surgery.

BACKGROUND: The Patient Reported Outcomes Measurement Information System (PROMIS) was developed to provide patient-reported outcome measures that are designed as being universally relevant across health conditions, low burden, and precise. A major problem for research and clinical practice in cerebral palsy (CP) is the void of outcomes instruments that are capable of evaluating the wide range of abilities and broad age spectrum inherent in this clinical population. Given the tremendous potential of PROMIS, the research questions for this study were "How do PROMIS pediatric computer adaptive tests and short forms detect change in children with CP following elective musculoskeletal surgery?" and "How do PROMIS instruments compare to the Pediatric Quality of Life Inventory Cerebral Palsy Module Version 3.0 (PedsQL CP), Pediatric Outcomes Data Collection Instrument (PODCI), the Timed Up and Go (TUG), and the Gross Motor Functional Measure (GMFM)." METHODS: PROMIS Pediatric computer adaptive tests and short forms and the PedsQL, PODCI, TUG, and GMFM were administered before and after surgery. Effect size (ES) and standardized response mean (SRM) were calculated. Floor and ceiling effects were evaluated and, exposure rates for the PROMIS item banks were examined. RESULTS: ES and SRM for all PROMIS Pediatric Measures were nonsignificant. PedsQL CP detected significant, positive change in mobility at 6 (ES=0.26; SRM=0.31) and 12 (ES=0.36; SRM=0.36) months; pain at 12 months (ES=0.29; SRM=0.34); and fatigue at 6 (ES=0.24; SRM=0.22) and 12 (ES=0.36; SRM=0.41) months. Significant negative changes were detected by the PODCI (ES=-0.20; SRM=-0.26), GMFM (ES=-0.13; SRM=-0.24), and TUG (ES=-0.29; SRM=-0.25). Ceiling effects were high. Exposure to an appropriate range of the PROMIS Mobility item bank was limited. CONCLUSIONS: PROMIS measures were less able to detect change than other measures. PROMIS measures may be improved by tailoring start/stop rules or by adding items to include content appropriate for children with mobility impairments. LEVEL OF EVIDENCE: Level III-diagnostic study.

Tracking functional status across the spinal cord injury lifespan: linking pediatric and adult patient-reported outcome scores.

OBJECTIVE: To use item response theory (IRT) methods to link scores from 2 recently developed contemporary functional outcome measures, the adult Spinal Cord Injury-Functional Index (SCI-FI) and the Pedi SCI (both the parent version and the child version). DESIGN: Secondary data analysis of the physical functioning items of the adult SCI-FI and the Pedi SCI instruments. We used a nonequivalent group design with items common to both instruments and the Stocking-Lord method for the linking. Linking was conducted so that the adult SCI-FI and Pedi SCI scaled scores could be compared. SETTING: Community. PARTICIPANTS: This study included a total sample of 1558 participants. Pedi SCI items were administered to a sample of children (n=381) with SCI aged 8 to 21 years, and of parents/caregivers (n=322) of children with SCI aged 4 to 21 years. Adult SCI-FI items were administered to a sample of adults (n=855) with SCI aged 18 to 92 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Five scales common to both instruments were included in the analysis: Wheelchair, Daily Routine/Self-care, Daily Routine/Fine Motor, Ambulation, and General Mobility functioning. RESULTS: Confirmatory factor analysis and exploratory factor analysis results indicated that the 5 scales are unidimensional. A graded response model was used to calibrate the items. Misfitting items were identified and removed from the item banks. Items that function differently between the adult and child samples (ie, exhibit differential item functioning) were identified and removed from the common items used for linking. Domain scores from the Pedi SCI instruments were transformed onto the adult SCI-FI metric. CONCLUSIONS: This IRT linking allowed estimation of adult SCI-FI scale scores based on Pedi SCI scale scores and vice versa; therefore, it provides clinicians with a means of tracking long-term functional data for children with an SCI across their entire lifespan.

An examination of the PROMIS(®) pediatric instruments to assess mobility in children with cerebral palsy.

PURPOSE: The Patient-Reported Outcomes Measurement Information System (PROMIS(®)) provides adult and pediatric self-report measures of health-related quality of life designed for use across medical conditions and the general population. The purpose of this study was to examine the feasibility and validity of the PROMIS(®) Pediatric Short Form and computer-adaptive test (CAT) mobility measures in children with cerebral palsy (CP). METHODS: Eighty-two children with CP completed self-report (PROMIS(®) Mobility Short Form, PROMIS(®) Mobility CAT, Pediatric Quality of Life Inventory™) and performance-based assessments of mobility (Timed Up and Go, Gross Motor Function Measure). Parents provided three proxy reports of child mobility (Pediatric Outcomes Data Collection Instrument, Functional Assessment Questionnaire, Shriners Hospitals for Children CP-CAT). Validity of PROMIS(®) instruments was examined through correlations with other measures and "known groups" analyses determined by Gross Motor Function Classification System (GMFCS). RESULTS: On average, the PROMIS(®) CAT required less than seven items and 2 minutes to administer. Both PROMIS(®) measures showed moderate to high correlations with child- and parent-proxy report of child mobility; correlations with performance-based measure were small for the PROMIS(®) Short Form and non-significant for the PROMIS(®) CAT. All measures except for the PROMIS(®) CAT were able to distinguish between GMFCS categories. CONCLUSIONS: Results support the convergent and discriminant validity of the pediatric PROMIS(®) Mobility Short Form in children with CP. The PROMIS(®) Mobility CAT correlates well with child report and parent report of mobility but not with performance-based measures and does not differentiate between known mobility groups.

Development of a computer-adaptive physical function instrument for Social Security Administration disability determination.

OBJECTIVES: To develop and test an instrument to assess physical function for Social Security Administration (SSA) disability programs, the SSA-Physical Function (SSA-PF) instrument. Item response theory (IRT) analyses were used to (1) create a calibrated item bank for each of the factors identified in prior factor analyses, (2) assess the fit of the items within each scale, (3) develop separate computer-adaptive testing (CAT) instruments for each scale, and (4) conduct initial psychometric testing. DESIGN: Cross-sectional data collection; IRT analyses; CAT simulation. SETTING: Telephone and Internet survey. PARTICIPANTS: Two samples: SSA claimants (n=1017) and adults from the U.S. general population (n=999). INTERVENTIONS: None. MAIN OUTCOME MEASURES: Model fit statistics, correlation, and reliability coefficients. RESULTS: IRT analyses resulted in 5 unidimensional SSA-PF scales: Changing & Maintaining Body Position, Whole Body Mobility, Upper Body Function, Upper Extremity Fine Motor, and Wheelchair Mobility for a total of 102 items. High CAT accuracy was demonstrated by strong correlations between simulated CAT scores and those from the full item banks. On comparing the simulated CATs with the full item banks, very little loss of reliability or precision was noted, except at the lower and upper ranges of each scale. No difference in response patterns by age or sex was noted. The distributions of claimant scores were shifted to the lower end of each scale compared with those of a sample of U.S. adults. CONCLUSIONS: The SSA-PF instrument contributes important new methodology for measuring the physical function of adults applying to the SSA disability programs. Initial evaluation revealed that the SSA-PF instrument achieved considerable breadth of coverage in each content domain and demonstrated noteworthy psychometric properties.

Development of an instrument to measure behavioral health function for work disability: item pool construction and factor analysis.

OBJECTIVES: To develop a broad set of claimant-reported items to assess behavioral health functioning relevant to the Social Security disability determination processes, and to evaluate the underlying structure of behavioral health functioning for use in development of a new functional assessment instrument. DESIGN: Cross-sectional. SETTING: Community. PARTICIPANTS: Item pools of behavioral health functioning were developed, refined, and field tested in a sample of persons applying for Social Security disability benefits (N=1015) who reported difficulties working because of mental or both mental and physical conditions. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Social Security Administration Behavioral Health (SSA-BH) measurement instrument. RESULTS: Confirmatory factor analysis (CFA) specified that a 4-factor model (self-efficacy, mood and emotions, behavioral control, social interactions) had the optimal fit with the data and was also consistent with our hypothesized conceptual framework for characterizing behavioral health functioning. When the items within each of the 4 scales were tested in CFA, the fit statistics indicated adequate support for characterizing behavioral health as a unidimensional construct along these 4 distinct scales of function. CONCLUSIONS: This work represents a significant advance both conceptually and psychometrically in assessment methodologies for work-related behavioral health. The measurement of behavioral health functioning relevant to the context of work requires the assessment of multiple dimensions of behavioral health functioning. Specifically, we identified a 4-factor model solution that represented key domains of work-related behavioral health functioning. These results guided the development and scale formation of a new SSA-BH instrument.

Conceptual foundation for measures of physical function and behavioral health function for Social Security work disability evaluation.

Physical and mental impairments represent the 2 largest health condition categories for which workers receive Social Security disability benefits. Comprehensive assessment of physical and mental impairments should include aspects beyond medical conditions such as a person's underlying capabilities as well as activity demands relevant to the context of work. The objective of this article is to describe the initial conceptual stages of developing new measurement instruments of behavioral health and physical functioning relevant for Social Security work disability evaluation purposes. To outline a clear conceptualization of the constructs to be measured, 2 content models were developed using structured and informal qualitative approaches. We performed a structured literature review focusing on work disability and incorporating aspects of the International Classification of Functioning, Disability and Health as a unifying taxonomy for framework development. Expert interviews provided advice and consultation to enhance face validity of the resulting content models. The content model for work-related behavioral health function identifies 5 major domains: (1) behavior control, (2) basic interactions, (3) temperament and personality, (4) adaptability, and (5) workplace behaviors. The content model describing physical functioning includes 3 domains: (1) changing and maintaining body position, (2) whole-body mobility, and (3) carrying, moving, and handling objects. These content models informed subsequent measurement properties including item development and measurement scale construction, and provided conceptual coherence guiding future empirical inquiry. The proposed measurement approaches show promise to comprehensively and systematically assess physical and behavioral health functioning relevant to work.

Development of a self-report physical function instrument for disability assessment: item pool construction and factor analysis.

OBJECTIVES: To build a comprehensive item pool representing work-relevant physical functioning and to test the factor structure of the item pool. These developmental steps represent initial outcomes of a broader project to develop instruments for the assessment of function within the context of Social Security Administration (SSA) disability programs. DESIGN: Comprehensive literature review; gap analysis; item generation with expert panel input; stakeholder interviews; cognitive interviews; cross-sectional survey administration; and exploratory and confirmatory factor analyses to assess item pool structure. SETTING: In-person and semistructured interviews and Internet and telephone surveys. PARTICIPANTS: Sample of SSA claimants (n=1017) and a normative sample of adults from the U.S. general population (n=999). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Model fit statistics. RESULTS: The final item pool consisted of 139 items. Within the claimant sample, 58.7% were white; 31.8% were black; 46.6% were women; and the mean age was 49.7 years. Initial factor analyses revealed a 4-factor solution, which included more items and allowed separate characterization of: (1) changing and maintaining body position, (2) whole body mobility, (3) upper body function, and (4) upper extremity fine motor. The final 4-factor model included 91 items. Confirmatory factor analyses for the 4-factor models for the claimant and the normative samples demonstrated very good fit. Fit statistics for claimant and normative samples, respectively, were: Comparative Fit Index=.93 and .98; Tucker-Lewis Index=.92 and .98; and root mean square error approximation=.05 and .04. CONCLUSIONS: The factor structure of the physical function item pool closely resembled the hypothesized content model. The 4 scales relevant to work activities offer promise for providing reliable information about claimant physical functioning relevant to work disability.

Scale refinement and initial evaluation of a behavioral health function measurement tool for work disability evaluation.

OBJECTIVE: To use item response theory (IRT) data simulations to construct and perform initial psychometric testing of a newly developed instrument, the Social Security Administration Behavioral Health Function (SSA-BH) instrument, that aims to assess behavioral health functioning relevant to the context of work. DESIGN: Cross-sectional survey followed by IRT calibration data simulations. SETTING: Community. PARTICIPANTS: Sample of individuals applying for Social Security Administration disability benefits: claimants (n=1015) and a normative comparative sample of U.S. adults (n=1000). INTERVENTIONS: None. MAIN OUTCOME MEASURE: SSA-BH measurement instrument. RESULTS: IRT analyses supported the unidimensionality of 4 SSA-BH scales: mood and emotions (35 items), self-efficacy (23 items), social interactions (6 items), and behavioral control (15 items). All SSA-BH scales demonstrated strong psychometric properties including reliability, accuracy, and breadth of coverage. High correlations of the simulated 5- or 10-item computer adaptive tests with the full item bank indicated robust ability of the computer adaptive testing approach to comprehensively characterize behavioral health function along 4 distinct dimensions. CONCLUSIONS: Initial testing and evaluation of the SSA-BH instrument demonstrated good accuracy, reliability, and content coverage along all 4 scales. Behavioral function profiles of Social Security Administration claimants were generated and compared with age- and sex-matched norms along 4 scales: mood and emotions, behavioral control, social interactions, and self-efficacy. Using the computer adaptive test-based approach offers the ability to collect standardized, comprehensive functional information about claimants in an efficient way, which may prove useful in the context of the Social Security Administration's work disability programs.

Validity of computer adaptive tests of daily routines for youth with spinal cord injury.

OBJECTIVE: To evaluate the accuracy of computer adaptive tests (CATs) of daily routines for child- and parent-reported outcomes following pediatric spinal cord injury (SCI) and to evaluate the validity of the scales. METHODS: One hundred ninety-six daily routine items were administered to 381 youths and 322 parents. Pearson correlations, intraclass correlation coefficients (ICC), and 95% confidence intervals (CI) were calculated to evaluate the accuracy of simulated 5-item, 10-item, and 15-item CATs against the full-item banks and to evaluate concurrent validity. Independent samples t tests and analysis of variance were used to evaluate the ability of the daily routine scales to discriminate between children with tetraplegia and paraplegia and among 5 motor groups. RESULTS: ICC and 95% CI demonstrated that simulated 5-, 10-, and 15-item CATs accurately represented the full-item banks for both child- and parent-report scales. The daily routine scales demonstrated discriminative validity, except between 2 motor groups of children with paraplegia. Concurrent validity of the daily routine scales was demonstrated through significant relationships with the FIM scores. CONCLUSION: Child- and parent-reported outcomes of daily routines can be obtained using CATs with the same relative precision of a full-item bank. Five-item, 10-item, and 15-item CATs have discriminative and concurrent validity.

Accuracy and precision of the Pediatric Evaluation of Disability Inventory computer-adaptive tests (PEDI-CAT).

AIM: The aims of the study were to: (1) build new item banks for a revised version of the Pediatric Evaluation of Disability Inventory (PEDI) with four content domains: daily activities, mobility, social/cognitive, and responsibility; and (2) use post-hoc simulations based on the combined normative and disability calibration samples to assess the accuracy and precision of the PEDI computer-adaptive tests (PEDI-CAT) compared with the administration of all items. METHOD: Parents of typically developing children (n = 2205) and parents of children and adolescents with disabilities (n = 703) between the ages of 0 and 21 years, stratified by age and sex, participated by responding to PEDI-CAT surveys through an existing Internet opt-in survey panel in the USA and by computer tablets in clinical sites. RESULTS: Confirmatory factor analyses supported four unidimensional content domains. Scores using the real data post hoc demonstrated excellent accuracy (intraclass correlation coefficients ≥ 0.95) with the full item banks. Simulations using item parameter estimates demonstrated relatively small bias in the 10-item and 15-item CAT versions; error was generally higher at the scale extremes. INTERPRETATION: These results suggest the PEDI-CAT can be an accurate and precise assessment of children's daily performance at all functional levels.

Linking the activity measure for post acute care and the quality of life outcomes in neurological disorders.

OBJECTIVE: To use item response theory (IRT) methods to link physical functioning items in the Activity Measure for Post Acute Care (AM-PAC) and the Quality of Life Outcomes in Neurological Disorders (Neuro-QOL). DESIGN: Secondary data analysis of the physical functioning items of AM-PAC and Neuro-QOL. We used a nonequivalent group design with 36 core items common to both instruments and a test characteristic curve transformation method for linking AM-PAC and Neuro-QOL scores. Linking was conducted so that both raw and scaled AM-PAC and Neuro-QOL scores (mean ± SD converted-logit scores, 50 ± 10) could be compared. SETTING: AM-PAC items were administered to rehabilitation patients in post-acute care (PAC) settings. Neuro-QOL items were administered to a community sample of adults through the Internet. PARTICIPANTS: PAC patients (N=1041) for the AM-PAC sample and community-dwelling adults (N=549) for the Neuro-QOL sample. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Mobility (N=25) and activity of daily living (ADL) items (N=11) common to both instruments were included in analysis. RESULTS: Neuro-QOL items were linked to the AM-PAC scale by using the generalized partial credit model. Mobility and ADL subscale scores from the 2 instruments were calibrated to the AM-PAC metric. CONCLUSIONS: An IRT-based linking method placed AM-PAC and Neuro-QOL mobility and ADL scores on a common metric. This linking allowed estimation of AM-PAC mobility and ADL subscale scores based on Neuro-QOL mobility and ADL subscale scores and vice versa. The accuracy of these results should be validated in a future sample in which participants respond to both instruments.

Precision and content range of a parent-reported item bank assessing lower extremity and mobility skills in children with cerebral palsy.

AIM: The aim of this study was to determine the psychometric properties, content range, and measurement precision of a lower extremity physical functioning and mobility skills item bank (LE85) in children with cerebral palsy (CP). METHOD: Lower extremity functioning and mobility skill items were administered to 308 parents of children (169 males, 139 females; mean age 10y 8mo, SD 4y) with spastic CP (145 diplegia, 73 hemiplegia, 89 quadriplegia; [for one person type of CP was unknown]) classified using the Gross Motor Function Classification System (75 level I, 91 level II, 79 level III, 37 level IV, 26 level V). Additional legacy measures were administered to assess concurrent validity. Psychometric characteristics, differential item functioning, content range, and score precision were examined. RESULTS: The LE85 had acceptable psychometric properties. Content range matched the ability range of the sample population and exceeded legacy measures with minimal differential item functioning. The LE85 had good correlation with the Paediatric Outcomes Data Collection Instrument, Functional Independence Measure for Children, Gillette Functional Assessment Questionnaire, and Paediatric Quality of Life Inventory-CP module (range r=0.63-0.86). Precision of the LE85 and 10-item simulated computer adaptive test scores outperformed legacy measures. INTERPRETATION: The LE85 appears to be suitable to administer as a computer adaptive test to measure lower extremity physical functioning and mobility in children with CP.

Validity and reliability of physical functioning computer-adaptive tests for children with cerebral palsy.

BACKGROUND: The purpose of this study was to assess the concurrent validity and reliability of scores from 4 new parent-report computer-adapted testing (CAT) programs developed to measure the physical functioning of children with cerebral palsy (CP). The Shriners Hospitals for Children CP-CAT battery includes upper-extremity skills, lower-extremity and mobility skills, activity, and global physical health. METHODS: This was a prospective study of 91 children with CP who were tested cross-sectionally and 27 children with CP who were administered the CP-CAT programs twice within approximately a 1-month interval. We examined the concurrent validity of the 4 Shriners Hospitals for Children CP-CAT programs by Pearson correlations with comparative parent-report instruments. The scale reliability was tested by developing estimates of marginal reliability; test-retest reliability was assessed by intraclass correlations. RESULTS: Pearson correlations were moderate to high in matching content domains of the CATs with the comparison measures. Marginal reliability estimates were always better for the CAT program than the comparative instruments. Average test-retest reliability using Intraclass correlations across the 4 CATs was ICC3,1=0.91 with a range of 0.88 to 0.94. CONCLUSIONS: We found the CAT scores to be related to expected domains from external instruments, to have good scale reliability, and to have stable scores as determined by test-retest reliability. These results support the use of parent-report CATs in the assessment of physical functioning in children with CP.

Children's and parents' perspectives about activity performance and participation after spinal cord injury: initial development of a patient-reported outcome measure.

OBJECTIVE: To report on a cognitive testing study on newly constructed items designed to evaluate client-reported outcomes of activity performance and participation after spinal cord injury (SCI). METHOD: Thirty-three children with SCI and 13 caregivers participated in cognitive testing interviews. Open-ended questions were used to gain a better understanding of activity performance and participation. The interviews were transcribed verbatim. A thematic analysis was carried out independently by 2 researchers, and key sentences and phrases from both analyses were merged. RESULTS: Four themes were defined: (1) apprehension related to activity performance and participation, (2) reference point, (3) missing out, and (4) autonomy. CONCLUSION: Insight into children's and caregivers' perspectives provided important information that helped refine the wording of test items and response scales. The theme of autonomy provided a stronger catalyst to solidify items for both child- and parent-reported outcomes. This study further validated the complexity of the construct of participation.

Functional recovery in children and adolescents with spinal cord injury.

PURPOSE: To examine functional recovery in mobility and self-care measured using the Pediatric Evaluation of Disability Inventory (PEDI) in children with spinal cord injury (SCI) during an inpatient rehabilitation stay and to identify how demographic and clinical variables relate to functional recovery. METHODS: PEDI scores were collected through retrospective chart review for 32 children and adolescents with SCI (mean age, 10.6 +/- 6.2 years; range, 1-19 years) admitted to an inpatient physical rehabilitation program between 1995 and 2007. RESULTS: Children with SCI showed significantly improved functional skill recovery and reduced caregiver assistance for the PEDI mobility and self-care domains after rehabilitation. Item analyses suggested more recovery in mobility than in self-care skills. Children with incomplete injury gained more independence in self-care than those with complete injury. CONCLUSIONS: Children with SCI showed improved functional skills and reduced need for caregiver assistance as measured by the PEDI during inpatient rehabilitation.

Lessons from use of the Pediatric Evaluation of Disability Inventory: where do we go from here?

PURPOSE: The purpose of this article is to review the innovations, applications, and effect of the original Pediatric Evaluation of Disability Inventory (PEDI) published in 1992 and to describe planned revisions. SUMMARY OF KEY POINTS: During the past decade, the PEDI has helped to shift thinking from a developmental to a functional focus. Using the PEDI, researchers and clinicians worldwide have highlighted variations in functional skill acquisition in clinical populations, the importance of recognizing cultural differences, and the value of documenting functional progress in relation to interventions. CONCLUSIONS: The PEDI has had a rich tradition in helping to document functional development. New methods are proposed for the next generation of the PEDI by using item banks and computer adaptive testing. RECOMMENDATIONS FOR CLINICAL PRACTICE: The computer adaptive testing feature and the revised and expanded content of the new PEDI will enable therapists to more efficiently assess children's functioning to a broader age group of children.

Development of a parent-report computer-adaptive test to assess physical functioning in children with cerebral palsy I: lower-extremity and mobility skills.

The objective of this project was to develop computer-adaptive tests (CATs) using parent reports of physical function in children and adolescents with cerebral palsy (CP). The specific aims of this study were to (1) examine the psychometric properties of an item bank of lower-extremity and mobility skills for children with CP; (2) evaluate a CAT using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) and the Functional Assessment Questionnaire (FAQ); and (4) establish the discriminant validity of simulated CATs with Gross Motor Function Classification System (GMFCS) levels and CP type (diplegia, hemiplegia, or quadriplegia). Parents (n=190) of children and adolescents with spastic diplegic (48%), hemiplegic (22%), or quadriplegic (30%) CP consisting of 108 males and 82 females with a mean age of 10 years 7 months (SD 4y 1mo, range 2-21y) and in GMFCS levels I to V participated in item pool calibration and completed the PODCI and FAQ. Confirmatory factor analyses supported a unidimensional model for the 45 basic lower-extremity and mobility items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficients [ICCs] >0.91) with the full item bank and had high correlations with PODCI transfers and mobility (ICC = 0.86) and FAQ scores (ICC = 0.77). All CATs discriminated among GMFCS levels and CP type. The lower-extremity and mobility skills item bank and simulated CATs demonstrated excellent performance over a wide span of ages and severity levels.

Development of a parent-report computer-adaptive test to assess physical functioning in children with cerebral palsy II: upper-extremity skills.

The specific aims of this study were to (1) examine the psychometric properties (unidimensionality, differential item functioning, scale coverage) of an item bank of upper-extremity skills for children and adolescents with cerebral palsy (CP); (2) evaluate a simulated computer-adaptive test (CAT) using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) upper-extremity core scale; and (4) determine the discriminant validity of the simulated CAT with Manual Ability Classification System (MACS) levels and CP type (i.e. diplegia, hemiplegia, or quadriplegia). Parents (n=180) of children and adolescents with CP (spastic diplegia 49%, hemiplegia 22%, or quadriplegia 28%) consisting of 102 males and 78 females with a mean age of 10 years 6 months (SD 4y 1mo, range 2-21y), and MACS levels I through V participated in calibration of an item pool and completed the PODCI. Confirmatory factor analyses supported a unidimensional model using 49 of the 53 upper-extremity items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficient [ICCs] >0.93) with the full item bank, had high correlations with the PODCI upper-extremity core scale score (ICC 0.79), and discriminated among MACS levels. The simulated CATs demonstrated excellent overall content coverage over a wide age span and severity of upper-extremity involvement. The future development and refinement of CATs for parent report of physical function in children and adolescents with CP is supported by our work.

Creating a computer adaptive test version of the late-life function and disability instrument.

BACKGROUND: This study applied item response theory (IRT) and computer adaptive testing (CAT) methodologies to develop a prototype function and disability assessment instrument for use in aging research. Herein, we report on the development of the CAT version of the Late-Life Function and Disability Instrument (Late-Life FDI) and evaluate its psychometric properties. METHODS: We used confirmatory factor analysis, IRT methods, validation, and computer simulation analyses of data collected from 671 older adults residing in residential care facilities. We compared accuracy, precision, and sensitivity to change of scores from CAT versions of two Late-Life FDI scales with scores from the fixed-form instrument. Score estimates from the prototype CAT versus the original instrument were compared in a sample of 40 older adults. RESULTS: Distinct function and disability domains were identified within the Late-Life FDI item bank and used to construct two prototype CAT scales. Using retrospective data, scores from computer simulations of the prototype CAT scales were highly correlated with scores from the original instrument. The results of computer simulation, accuracy, precision, and sensitivity to change of the CATs closely approximated those of the fixed-form scales, especially for the 10- or 15-item CAT versions. In the prospective study, each CAT was administered in <3 minutes and CAT scores were highly correlated with scores generated from the original instrument. CONCLUSIONS: CAT scores of the Late-Life FDI were highly comparable to those obtained from the full-length instrument with a small loss in accuracy, precision, and sensitivity to change.