• Physical Therapy Korea
• /
• v.24 no.4
• /
• pp.20-28
• /
• 2017

Background: Rasch analysis has the advantage of placing both the items and the person along a single ratio scale and calibrates person ability and item difficulty onto an interval scale by logits. Therefore, Rasch analysis has been recommended as a better method for evaluating functional outcome questionnaires than traditional analyses. Objects: The aim of current study was to investigate item fit, item difficulty, rating scale, and separation index of the Korean version of the Fullerton Advanced Balance (KFAB) scale using Rasch analysis. Methods: In total, 93 patients with stroke (male=58, female=35) participated in this study. To investigate the item fit, difficulty, rating scale, and separation index of the KFAB scale, Rasch analysis was completed by the Winsteps software program. Results: In this study, all items of the KFAB scale were included in the Rasch model. The most difficult item was 'standing with feet together and eyes closed', and the easiest item was 'two-footed jump'. The rating scale was a 4-point scale instead of the original 5-point scale. Person and item separation indices showed high values that can identify a person with a wide range of balance ability. Conclusion: The KFAB scale appears to be a reliable and valid tool to assess balance function in patients with stroke. Furthermore, the scale was found to discriminate among stroke patients of varying balance abilities.

• Physical Therapy Korea
• /
• v.11 no.2
• /
• pp.9-16
• /
• 2004

The purpose of this study was to validate the Korean version of the Gross Motor Function Measure (GMFM) using Rasch analysis. The data was obtained from the assessments of 59 children with cerebral palsy in Korea and were applied to Rasch's rating scale model to estimate the difficulty and goodness-of-fit of each item. Rasch modeling helped us to identify 76 items from the original 88-item GMFM that form an unidimensional hierarchical scale to rearrange 76 items in order of difficulty. Reliability coefficients of the 88-item and 76-item GMFM were .99 and .99, respectively. In this preliminary report, the Korean version of GMFM seems to have significant validity and reliability. These results may be useful in assessment of gross motor functions in children with cerebral palsy.

• Physical Therapy Korea
• /
• v.21 no.2
• /
• pp.74-81
• /
• 2014

The versions of the Oswestry disability questionnaire (ODQ) is regarded as one of the most extensively used condition-specific instruments measuring disability resulting from low back pain. It has been shown to have adequate psychometrics, reliability, validity, and responsiveness as a whole, yet the summated total score of the instrument often provide little information to rehabilitation clinicians. A keyform analysis based on Rasch measurement model is an innovative way of illustrating the specific test items that an individual may or may not perform. By applying the keyform of the Rasch measurement model to the ODQ, rehabilitation clinicians may able to select more challenging ODQ items matching an individual's ability and document them as attainable treatment goals. The results demonstrated how a keyform analysis assist to setting possible goals for the treatment of individuals with low back pain. Forty-two individuals with low back pain were recruited from rehabilitation clinics in Gainesville, Florida. A series of Rasch analyses on the 10 items of the ODQ were performed using Winsteps software. The performance of two individuals on those 10 items was illustrated on the keyform. The keyform analysis of the Rasch measurement model may be translated into a useful tool for making clinical judgements.

• Korean Journal of Social Welfare
• /
• v.59 no.4
• /
• pp.273-296
• /
• 2007

In this Study, to reconstruct the disability identity scale(Lee and Shin, 2006)), Rasch rating scale model was applied to the four sub-dimensions of the Disability Identity Scale in a sample of spinal cord injuries(N=397). The Disability Identity Scale was verified by explorative factor analysis and confirmatory factor analysis. However, factor analytic procedures can't evaluate item-fit indices, item difficulty, and appropriate scale category. A number of limitations posed by confirmatory factor analytic procedures can be averted with the use of Rasch rating scale model which is in the item response theory(IRT). So in this study, Rasch model was applied to the Disability Identity Scale. Results revealed that (A) 20 items were selected from Rasch model, (B) the difficulty level of the Disability Identity Scale was the average level, (C) 4-point rating scale was appropriate for the Disability Identity Scale. Finally, we could suggest that the sub-dimensions concepts of the disability identity became clearer and items were to the good fitting.

• Physical Therapy Korea
• /
• v.23 no.1
• /
• pp.46-54
• /
• 2016

Background: Rasch analysis estimates the probability that a respondent will endorse an item and select a particular rating for that item. It has the advantage of placing both the items and the person along a single ration scale and calibrates person ability and item difficulty onto an interval scale by logits. In addition, Rasch analysis is a useful tool for exploring the validity of questionnaires that have been developed using traditional methods. Therefore, it has been recommended as a method for developing and evaluating functional outcome measures. Objects: The purpose of this study was to investigate the item fit, item difficulty, and rating scale of the Korean version of the Fullerton Advanced Balance Scale (KFAB) using Rasch analysis. Methods: Total 97 subjects (39 males and 58 females) with dwelling elderly adults were participated, but 3 people were excluded for misfit persons. Rasch analysis was then done by means of the Winsteps program to determine the item fit, item difficulty, rating scale, and reliability of the KFAB. Results: In this study, the 'standing with feet together and eyes closed', 'two-footed jump', 'walk with head turns', and 'stand on foam, eyes closed' items shown misfit statistics. The most difficult item was 'stand on one leg', whereas the easiest item was 'turn in full circle'. The rating scale was acceptable with all criteria. Both item and person separation indices and reliability showed acceptable values. This would indicated that each domain covers a useful range of item difficulty that is appropriate for measuring a person with a wide range of functional ability. Conclusion: The KFAB has been proven reliable, valid and an appropriate tool with which to evaluate the balance of the elderly people.

• Physical Therapy Korea
• /
• v.15 no.3
• /
• pp.26-34
• /
• 2008

The purposes of this study were to assess and modify the original classification categories of the modified Oswestry Low Back Pain Disability Questionnaire (ODQ) and to determine the unidimensionality of the modified ODQ applying Rasch Analysis. The data were obtained from 108 work-related low back pain patients by physical therapists. Construct validity of the scale using the Rasch model required the structure of the rating scale to be modified from 6 response levels to 4 response levels. Eight items from the modified ODQ fit the Rasch model. The items, "pain intensity" and "social life" showed misfit statistics. In general, the order of item difficulty of the remaining 8 items showed a logical item difficulty hierarchy with the "changing degree of pain" item being the most difficult and the "walk" item being the easiest. The results showed that further study is needed to expand the construct of ODQ including additional higher-level items related to work activities. This study may be useful for establishing a standard method to assess the functionality of low back pain patients.

• Journal of the Korean School Mathematics Society
• /
• v.24 no.1
• /
• pp.1-18
• /
• 2021

The purpose of the study was to examine the psychometric properties of the personal teaching efficacy of the Mathematics Teaching Efficacy Beliefs Instrument and revise the scale for the use of Korean elementary school teachers. Data were collected from 299 elementary teachers. A Rasch analysis was used to evaluate unidimensionality and appropriateness of category use and item difficulty levels. Moreover, person separation and reliability as well as item separation and reliability were examined using the revised scale. Results suggested that the original personal teaching efficacy scale (13 items with five categories) had several problems in its psychometric properties. Thus, we revised the scale into eight items with four categories. The follow-up analysis results showed the revised scale provided sufficient psychometric properties for measuring Korean elementary school teachers' self-efficacy beliefs for teaching mathematics. Limitations and implications of the study were also discussed.

• Physical Therapy Korea
• /
• v.14 no.1
• /
• pp.82-89
• /
• 2007

The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is a valid and widely used instrument for the assessment of osteoarthritis patients. In this study, data was obtained from the out-patients with painful osteoarthritis of the knee. One hundred-three out-patients were interviewed by physical therapists. In an exploratory way, a Korean version of the KWOMAC was analyzed for unidimensionality, item separation, and item difficulty using the Winsteps programs. Ninety-five patients with osteoarthritis of the knee over 65 years were analyzed for Rash analysis. In the analysis several functional items poorly fit to the model. These items included "heavy domestic duties" and "standing". In the pain domain, one item ("at night while in bed") did not fit the model. In the stiffness domain one item ("after sitting, lying, or resting later in the day") did not fit the model. Although 4 items from the 3 domains (pain, stiffness, function domain) do not fit well, the KWOMAC domains were confirmed by Rasch analysis. Thus the KWOMAC needs to be further examined before it can be used to properly determine the health status of the elderly with OA.

• Physical Therapy Korea
• /
• v.14 no.1
• /
• pp.37-45
• /
• 2007

This study was designed to examine, applying Rasch analysis based on item response theory, the questionnaires of the Activities-Specific Balance Confidence (ABC) scale for the elderly. The subjects were 99 institutional older adults and clients of social welfare facilities. The subjects (17 men, 72 women) ranged in age from 65 to 94 years (mean age 76.5 yrs). The Winsteps software was used to assess whether the ABC scale fits the Rasch model, to estimate the score and to refine the rating scale. The results are as follows. Twenty-two subjects were excluded as misfit persons. Four items were found to be misfits and the order of difficulty of the remaining 12 items was rearranged. Their balance confidence is indicated by -.64~1.12 logit, and the transformation formula is score=[(logit score+2.76)/(2.76+3.48)]${\times}$100. The most difficult item was "Walk outside in icy sidewalks" and the easiest item was "Walk around house." In conclusion, the ABC scale for the elderly has been proven reliable and valid. Therefore, it is expected to be used as an effective examination tool for treatment planning and screening for older adults.

• Physical Therapy Korea
• /
• v.23 no.4
• /
• pp.71-80
• /
• 2016

Background: Functional capacity evaluations (FCEs) are designed to systematically assess the capacity to perform work-related tasks and to determine worker's ability to return to the previous job following work-related injuries. These evaluations may be rated either by clinician or worker. There has been a lack of consensus between the two scoring methods. Objects: This study aimed: 1) to confirm if the data are fit to the Rasch rating scale model and 2) to investigate the item-level concordance rate between the ratings of clinician and injured worker of the FCE. Methods: A cross-sectional study was conducted with a sample (n=124) of a rehabilitation program with the Occupational Rehabilitation Data Base for workers with low back pain. The functional capacity evaluation at admission and discharge was administered to clinicians and workers. The data were analyzed using both classical test theory-based Pearson's r and intra-class coefficient followed by item-level analysis with Rasch rating scale model. Results: All items of the FCE, except sitting items rated by clinician at admission and handling items rated by both clinician and worker throughout admission and discharge, were acceptable fit statistics with minor out of ranges for a misfit criterion. This may indicate that the items of the FCE overall fit to the Rasch rating scale model. Few problematic items responding differently to clinician and worker both at admission and discharge were detected with the differential item functioning analysis despite the excellent concordance rate using the two conventional statistics-sitting and handling items at admission and handling item at discharge. Conclusion: The item-level speculations using Rasch analysis of the FCE demonstrate that the ratings of clinician and self ratings of worker were psychometrically acceptable though there was an apparent discrepancy between the raters both at admission and discharge.