ICF-Based simple scale for children with cerebral palsy: Application of Mokken scale analysis and Rasch modeling

Using a nonparametric item response theory model to identify patterns of cognitive decline: The Mokken scale analysis

Cognitive decline, particularly in dementia, presents complex challenges in early detection and diagnosis. While Item Response Theory (IRT) has been instrumental in identifying patterns of cognitive impairment through psychometric tests, its parametric models often require large sample sizes and strict assumptions. This creates a need for more adaptable, less demanding analytical methods. This study aimed to evaluate the effectiveness of Mokken scale analysis (MSA), a nonparametric IRT model, in identifying hierarchical patterns of cognitive impairment from psychometric tests. Using data from 1164 adults over 60 years old, we applied MSA to the orientation subscale of ACE-III. Our analysis involved calculating scalability, monotone homogeneity, invariant item ordering (IIO) and response functions. The MSA effectively retrieved the hierarchical order of cognitive impairment patterns. Most items showed strong scalability and consistent patterns of cognitive performance. However, challenges with IIO were observed, particularly with items having adjacent difficulty parameters. The findings highlight MSA's potential as a practical alternative to parametric IRT models in cognitive impairment research. Its ability to provide valuable insights into patterns of cognitive deterioration, coupled with less stringent requirements, makes it a useful tool for clinicians and researchers.

Research Paradigm of the International Classification of Functioning, Disability and Health (ICF) With Item Response Theory: Clarification, Classification, and Challenge

BACKGROUND

The International Classification of Functioning, Disability and Health (ICF) is the worldwide terminology system for measuring health and disability at both individual and population levels. However, the underlying challenges remain in achieving widespread adoption and implementation of ICF within healthcare contexts, including the unequal interval scale of the ICF Likert-type qualifier system ranging from 0 to 4, a lack of consensus on conceptualization and grading criteria of ICF items, and an excessive number of ICF items associated with each disease. The utilization of item response theory (IRT) for ICF studies demonstrated potential benefits in addressing these issues. Here, a review attempted to provide clarification of two predominant needs (sufficiency and efficiency) and two dimensions of scoring principles (stratification and assignment principles) in the ICF.

METHODS

A literature search was conducted on the PubMed database, and 44 relative articles were selected. On this basis, this review was undertaken to track the research progress of the ICF based on the parameter IRT method, typically the Rasch model.

RESULTS

This review outlined the classification of Item response model (IRM) for ICF studies and summarized existing IRT-based ICF research paradigms. Moreover, this review identified blind spots regarding assignment principles and the difficulty parameter in current ICF-based IRT studies. The Mokken scale analysis (MSA), as a non-parametric IRT method, was introduced as a data shaping tool for parametric IRM. The pipeline of the ICF-based MSA-Rasch modeling might advance the understanding of ICF clinical application and shed light on a new paradigm of questionnaire design.

CONCLUSION

The advent of ICF-oriented IRM algorithms may advance the comprehension of ICF clinical application and pave the way for a new paradigm for IRT-derived ICF questionnaires, namely the parsimonious ICF core set. Additionally, the Wright map holds promise in facilitating insight into rehabilitation trajectories and personalizing rehabilitation goals.

Dysphagia-Specific Instrument Based on Item Response Theory and International Classification of Functioning, Disability and Health

This study aimed to identify functional challenges faced by individuals with non-esophageal dysphagia and to offer a tool for quantitatively evaluating the person abilities within the framework of the International Classification of Functioning, Disability and Health (ICF). Additionally, this study attempted to differentiate the personal abilities of individuals with dysphagia and hierarchize item difficulties using the ICF-based Item Response Theory (IRT) modeling approach. This cross-sectional study enrolled a cohort of 150 patients with dysphagia (105 male and 45 female) from a tertiary hospital in China. Participants were assigned to evaluate the 114-item ICF dysphagia questionnaire. To further assess their swallowing capabilities, eating patterns, quality of life, and nutritional status, participants underwent a battery of five additional scales. The ICF qualifiers underwent data shaping including dichotomization and missing value imputation, Mokken scale analysis (MSA) for checking unidimensionality, local independence, monotonicity, and invariant item ordering (IIO), and parametric IRT modeling for identifying an optimal model from the 1-parametric logistic model (1PLM), 2PLM, 3PLM, and 4PLM. Finally, we tested the robustness of the optimal model via Monte Carlo simulation and illustrated the usefulness of the model by its person-item map. The 1PLM emerged as the optimal model with a total of 50 ICF items (12 'd-Activities and Participation', 33 'b-Body Functions', and 5 'e-environmental' items). The final scale presented strong reliability with Cronbach's Alpha = 0.967. Furthermore, the scale showed good validity with a significant positive correlation (p < 0.001,r ^ Winsorized = 0.60) between model-estimated person abilities and swallowing-quality of life (SWAL-QoL) scores. The findings also demonstrated measurement equivalence of the final model for individuals with different genders or across various age groups. The utilization of the person-item map can effectively compare the difficulty levels of items with the abilities of patients, thereby facilitating the delivery of tailored care and precise rehabilitation strategies that match the individual competency of those suffering from dysphagia. This study developed a parsimonious dysphagia-specific ICF outcomes tool derived from the IRT, named iSWAL-Performance Scale. The findings complement quantitative information on the psychometric characteristics of this 50-item scale.

Interpretation of course conceptual structure and student self-efficacy: an integrated strategy of knowledge graphs with item response modeling

BACKGROUND

There is a scarcity of studies that quantitatively assess the difficulty and importance of knowledge points (KPs) depending on students' self-efficacy for learning (SEL). This study aims to validate the practical application of psychological measurement tools in physical therapy education by analyzing student SEL and course conceptual structure.

METHODS

From the "Therapeutic Exercise" course curriculum, we extracted 100 KPs and administered a difficulty rating questionnaire to 218 students post-final exam. The pipeline of the non-parametric Item Response Theory (IRT) and parametric IRT modeling was employed to estimate student SEL and describe the hierarchy of KPs in terms of item difficulty. Additionally, Gaussian Graphical Models with Non-Convex Penalties were deployed to create a Knowledge Graph (KG) and identify the main components. A visual analytics approach was then proposed to understand the correlation and difficulty level of KPs.

RESULTS

We identified 50 KPs to create the Mokken scale, which exhibited high reliability (Cronbach's alpha = 0.9675) with no gender bias at the overall or at each item level (p > 0.05). The three-parameter logistic model (3PLM) demonstrated good fitness with questionnaire data, whose Root Mean Square Error Approximation was < 0.05. Also, item-model fitness unveiled good fitness, as indicated by each item with non-significant p-values for chi-square tests. The Wright map revealed item difficulty relative to SEL levels. SEL estimated by the 3PLM correlated significantly with the high-ability range of average Grade-Point Average (p < 0.05). The KG backbone structure consisted of 58 KPs, with 29 KPs overlapping with the Mokken scale. Visual analysis of the KG backbone structure revealed that the difficulty level of KPs in the IRT could not replace their position parameters in the KG.

CONCLUSION

The IRT and KG methods utilized in this study offer distinct perspectives for visualizing hierarchical relationships and correlations among the KPs. Based on real-world teaching empirical data, this study helps to provide a research foundation for updating course contents and customizing learning objectives.

TRIAL REGISTRATION

Not applicable.

Simplified functioning assessment for low back pain: ICF-based item response theory modelling

BACKGROUND

Despite the growing interest of the item response theory (IRT) in assessment of person abilities and functioning difficulties in screening tools, there is scarcity of research using IRT on ICF-based tools for persons with low back pain (LBP).

AIM

To generate and validate a parsimonious core set of ICF (PCSI) for LBP based on the IRT modelling.

DESIGN

A cross-sectional study.

SETTING

Nine hospitals in Jiangsu Province, China.

POPULATION

We recruited patients with LBP.

METHODS

All participants completed the 78 items of the comprehensive ICF Core Set for LBP. The five-point scoring system was converted to dichotomous data with 1 as functioning/independent and 0 as impairment/dependent. Psychometric properties of the data were examined using Mokken Scale analysis and parametric item response modelling.

RESULTS

This study recruited 306 participants (185 females and 121 males) with LBP. The overall median age of the study participants was 50.28 (95% CI 23.34; 82.05) years. We constructed a three-parameter logistic model with 28 ICF categories (8 of body function, 18 of activities and participation, and two of body structures). The internal consistency was good with Cronbach's alpha = 0.927 and latent class reliability coefficient (LCRC) = 0.955. The model was validated by significant correlations (P<0.001) of its estimated person abilities with the Oswestry Disability Index (ODI, r=-0.41), the Roland-Morris Disability Questionnaire (RMDQ, r=-0.57), the Physical Component Summary (PCS, r=0.63), and the Mental Component Summary (MCS, r = 0.46) of 12-Item Short Form Survey (SF-12). The person abilities and item difficulties were integrated into a Wright map that offered a background for making individualized clinical decisions.

CONCLUSIONS

The PCSI of LBP with 28 categories has good construct validity and internal consistency, and is a convenient instrument for assessing functioning among persons with LBP. The IRT model provided theoretical and algorithmic support for deriving a simplified model for functioning assessment hence serving a basis for formulating rehabilitation plans in clinical practice and research.

CLINICAL REHABILITATION IMPACT

A parsimonious core set of ICF (PCSI) for LBP based on the IRT modelling provides a background for making individualized clinical decisions based on item difficulties.