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.

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.