Analysis of the pediatric outcomes data collection instrument in ambulatory children with cerebral palsy using confirmatory factor analysis and item response theory methods

BACKGROUND: Traditional use of the Pediatric Outcomes Data Collection Instrument (PODCI) assumes that all items have the same structure, are measuring the intended constructs, and assess the right levels of function to show change after orthopaedic or neurological intervention. Item response theory (IRT) methods can statistically account for inherent differences in PODCI item characteristics and thus reveal attributes of the measure important to effectiveness research. Our study uses IRT methods to determine whether PODCI items fit the projected dimensional structure of the PODCI, assess function on each dimension at the right level for a population of ambulatory children with cerebral palsy (CP), and reveal changes after intervention in this population. METHODS: Proxy-reported PODCI questionnaires for 570 ambulatory children with CP were randomly divided into 2 groups for model creation and model testing using exploratory and then confirmatory factor analysis. The resulting model was compared with the projected dimensional structure, tested for fit of individual items, and examined for gaps and ceiling effects. Response changes at 1 year were compared between those with (n = 91) and without (n = 284) surgical intervention using paired t tests. RESULTS: Factor analysis reduced the projected dimensions from 5 to 4 for this population, resulting in dimensions for mobility, upper extremity function (UEF), comfort and general health, and self-worth. All but 3 items fit their respective dimensions; ceiling effects were noted in 3 dimensions. Responses showed changes in the comfort and general health, mobility, and UEF dimensions in those who had surgery; in those children who did not have surgery, only the UEF responses changed. CONCLUSIONS: The PODCI can show change after intervention when data are analyzed using IRT methods. Ceiling effects in 3 dimensions may limit the amount of change the PODCI can show in a population of ambulatory children with CP. LEVEL OF EVIDENCE: Level II. This was a retrospective investigation of a diagnostic tool, the PODCI, using a randomized cross-sectional design for model development, and a case-control design to assess sensitivity to change.     

Pediatric outcomes data collection instrument scores in ambulatory children with cerebral palsy: an analysis by age groups and severity level

BACKGROUND: The Pediatric Outcomes Data Collection Instrument (PODCI) was developed in 1994 as a patient-based tool for use across a broad age range and wide array of musculoskeletal disorders, including children with cerebral palsy (CP). The purpose of this study was to establish means and SDs of the Parent PODCI measures by age groups and Gross Motor Function Classification System (GMFCS) levels for ambulatory children with CP. METHODS: This instrument was one of several studied in a prospective, multicenter project of ambulatory patients with CP between the aged 4 and 18 years and GMFCS levels I through III. Participants included 338 boys and 221 girls at a mean age of 11.1 years, with 370 diplegic, 162 hemiplegic, and 27 quadriplegic. Both baseline and follow-up data sets of the completed Parent PODCI responses were statistically analyzed. RESULTS: Age was identified as a significant predictor of the PODCI measures of Upper Extremity Function, Transfers and Basic Mobility, Global Function, and Happiness With Physical Condition. Gross Motor Function Classification System levels was a significant predictor of Transfers and Basic Mobility, Sports and Physical Function, and Global Function. Pattern of involvement, sex, and prior orthopaedic surgery were not statistically significant predictors for any of the Parent PODCI measures. Mean and SD scores were calculated for age groups stratified by GMFCS levels. Analysis of the follow-up data set validated the findings derived from the baseline data. Linear regression equations were derived, with age as a continuous variable and GMFCS levels as a categorical variable, to be used for Parent PODCI predicted scores. CONCLUSIONS: The results of this study provide clinicians and researchers with a set of Parent PODCI values for comparison to age- and severity-matched populations of ambulatory patients with CP.     

Understanding the motives for food choice in Western Balkan Countries

Substantial empirical evidence exists regarding the importance of different factors underlying food choice in Western Europe. However, research results on eating habits and food choice in the Western Balkan Countries (WBCs) remain scarce. A Food Choice Questionnaire (FCQ), an instrument that measures the reported importance of nine factors underlying food choice, was administered to a representative sample of 3085 adult respondents in six WBCs. The most important factors reported are sensory appeal, purchase convenience, and health and natural content; the least important are ethical concern and familiarity. The ranking of food choice motives across WBCs was strikingly similar. Factor analysis revealed eight factors compared to nine in the original FCQ model: health and natural content scales loaded onto one factor as did familiarity and ethical concern; the convenience scale items generated two factors, one related to purchase convenience and the other to preparation convenience. Groups of consumers with similar motivational profiles were identified using cluster analysis. Each cluster has distinct food purchasing behavior and socio-economic characteristics, for which appropriate public health communication messages can be drawn.     

Hepatitis C virus testing,liver disease assessment and treatment uptake among people who inject drugs pre‐ and post‐universal access to direct‐acting antiviral treatment in Australia: The LiveRLife study

Gaps in hepatitis C virus (HCV) testing, diagnosis, liver disease assessment and treatment uptake among people who inject drugs (PWID) persist. We aimed to describe the cascade of HCV care among PWID in Australia, prior to and following unrestricted access to direct‐acting antiviral (DAA) treatment. Participants enrolled in an observational cohort study between 2014 and 2018 provided fingerstick whole‐blood samples for dried blood spot, Xpert HCV Viral Load and venepuncture samples. Participants underwent transient elastography and clinical assessment by a nurse or general practitioner. Among 839 participants (mean age 43 years), 66% were male (n = 550), 64% (n = 537) injected drugs in the previous month, and 67% (n = 560) reported currently receiving opioid substitution therapy. Overall, 45% (n = 380) had detectable HCV RNA, of whom 23% (n = 86) received HCV treatment within 12 months of enrolment. HCV treatment uptake increased from 2% in the pre‐DAA era to 38% in the DAA era. Significant liver fibrosis (F2‐F4) was more common in participants with HCV infection (38%) than those without (19%). Age 50 years or older (aOR, 2.88; 95% CI, 1.18‐7.04) and attending a clinical follow‐up with nurse (aOR, 3.19; 95% CI, 1.61‐6.32) or physician (aOR, 11.83; 95% CI, 4.89‐28.59) were associated with HCV treatment uptake. Recent injection drug use and unstable housing were not associated with HCV treatment uptake. HCV treatment uptake among PWID has increased markedly in the DAA era. Evaluation of innovative and simplified models of care is required to further enhance treatment uptake.