Development of a Keratoconus-Specific Questionnaire Using Rasch Analysis

Khadka, Jyoti; Schoneveld, P; Pesudovs, Konrad

doi:10.1097/opx.0000000000001035

Cited by 33 publications

(47 citation statements)

References 36 publications

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“…KEPAQ-E ended up consisting of a total of 7 questions, while the KEPAQ-F ended up consisting of a total of 9 questions. Both subscales demonstrate a good behavior, complying with the Rasch model expectations as specified by Khadka et al 6 ( Table 3). For the final version of the KEPAQ, questions in both sub-scales were rearranged from the easiest-toendorse to the hardest-to-endorse items.…”

Section: Final Version Of the Scalesupporting

confidence: 76%

“…Nowadays, Keratoconus Outcomes Research Questionnaire (KORQ) is the only questionnaire designed and explicitly validated in patients with keratoconus, developed by Khadka et al 6 and recently evaluated by Kandel et al 7 However, one of the main limitations of this instrument is that it ignores one of the most important elements in the compromise of QoL in patients with keratoconus and the profound emotional effect that the disease has on its daily functioning. Moshos et al 8 have shown that the presence of keratoconus is associated not only with a higher prevalence of clinical depression but also with a greater intensity of it.…”

Section: Introductionmentioning

confidence: 99%

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<p>Development and Validation of the “Keratoconus End-Points Assessment Questionnaire” (KEPAQ), a Disease-Specific Instrument for Evaluating Subjective Emotional Distress and Visual Function Through Rasch Analysis</p>

Balparda¹,

Herrera-Chalarca

Silva-Quintero

et al. 2020

OPTH

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Background: Keratoconus is a disease characterized by progressive distortion of the corneal anatomy, coupled with a decrease in vision. Assessing quality of life (QoL) in keratoconus is essential. So far, no instrument in the world has been designed to evaluate both visual function and emotional distress in this population. The purpose of the following study is to develop and validate the "Keratoconus End-Points Assessment Questionnaire" (KEPAQ) in a population of ectatic patients, the very first disease-specific scale to measure emotional latent traits in keratoconus. Methods: A last generation, Rasch analysis method was used for scale validation. First, a number of focus groups were carried out to create a pool of potential items. Then, a series of processes (such as "Content Validity Index") was carried out to develop a prior, 20question version of the KEPAQ. Then, a study including 150 keratoconus patients was performed, followed by a careful Rasch analysis to validate and optimize both sub-scales (Emotional Compromise, KEPAQ-E, and Functional Compromise, KEPAQ-F). Results: Initially, 86 items were considered as potential elements. After test optimization, 20 items were retained. A total of 150 patients with a confirmed diagnosis of keratoconus were included for the Rasch analysis. The mean age was 29.84 ± 9.96 years. In 150 patients, 12.6% had a history of keratoplasty, 46.0% had corneal rings, and 31.3% had crosslinking. For both sub-scales, misfitting items were removed until no misfitting was determined by repetitive Rasch runs. For the final version of the KEPAQ-E sub-scale, variance explained by the model was 62.4% with a dimensional scale. Person Separation Index and Person Number of Strata were 2.43 and 3.57, respectively. For the final version of the KEPAQ-F sub-scale, variance explained by the model was 61.3% with a unidimensional scale. Person Separation Index and Person Number of Strata were 3.19 and 4.59, respectively. Both sub-scales showed excellent Person Reliability. Conclusion: The KEPAQ is a robust scale, developed and validated through the latest theoretical models. It shows excellent psychometric properties, which render it extremely useful for both clinical and research use. To date, the KEPAQ is the only disease-specific scale worldwide to evaluate both functional and emotional compromise in keratoconus patients.

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Section: Final Version Of the Scalesupporting

confidence: 76%

Section: Introductionmentioning

confidence: 99%

<p>Development and Validation of the “Keratoconus End-Points Assessment Questionnaire” (KEPAQ), a Disease-Specific Instrument for Evaluating Subjective Emotional Distress and Visual Function Through Rasch Analysis</p>

Balparda¹,

Herrera-Chalarca

Silva-Quintero

et al. 2020

OPTH

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“…Rasch analysis is a widely accepted methodology to develop and validate PROMs including item banks [13,36]. The advantage of Rasch analysis is that it also provides surgical insights into whether an instrument could form a valid scale based on its assessment on a series of psychometric properties [37]. The following Rasch-based psychometric properties were assessed for the item bank [20,38].…”

Section: Psychometric Properties Assessment Using Rasch Analysismentioning

confidence: 99%

Exploring the potential for item banking in assessing quality of life for evaluating adolescent health interventions

Khadka

Chen

Ratcliffe

2020

Preprint

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Background To develop and validate an item bank using existing items from both preference and non-preference-based health-related quality of life (HRQoL) instruments targeted for application with adolescent populations. Methods Australian adolescents completed the Child Health Utility 9D (CHU9D), demographic details, self-rated health status, disability and one other instrument (either preference-based: Health Utilities Index (HUI) or EuroQoL-5 Dimension-Youth (EQ-5D-Y) or Assessment of Quality of Life (AQoL)-6D Adolescent or non-preference-based: Pediatric Quality of Life Inventory (PedsQL) Short Form 15 or KIDSCREEN-10) using online survey portals. Data from all the instruments were pooled together to create an item bank, which was then subjected to Rasch analysis to tests its psychometric properties. Validity of the item bank was assessed by testing its ability to discriminate varying levels of self-reported health, disability and socio-economic status (as approximated by the Family Affluence Scale). Results A total of 4,352 Australian adolescents aged 11–17 years from the general population participated. The CHU9D (common instrument) items were used as anchor items to create the item bank. Rasch analysis demonstrated that 2 of the 75 items (2.7%) misfit and were removed from the item bank. The 73-item item bank had adequate precision, no misfitting items, no item bias and demonstrated sufficient unidimensionality. In general boys exhibited higher HRQoL scores than girls (p = 0.001). More severe health status/disability and lower socio-economic status being associated with lower HRQoL (p < 0.0001). Conclusions The item bank demonstrated adequate Rasch-based psychometric properties and validity demonstrating the feasibility of the construction of an item bank in this context. The addition of more targeted items for adolescents in the general population and the addition of participants with more health impairments may improve the general applicability of the item bank for both general population and patient cohorts.

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“…(AS-20) 10 , Ocular Comfort Index (OCI) 11 , Ocular Surface Disease Index (OSDI) 11 , Brief Impact of Vision Impairment (IVI) questionnaire 12 , and the Keratoconus Outcomes Research Questionnaire (KORQ) 13 , to name but a few. This study describes the application of Rasch analysis to refine the descriptive system for the CAT-QoL instrument.…”

Section: Introductionmentioning

confidence: 99%

Refinement of the Child Amblyopia Treatment Questionnaire (CAT-QoL) using Rasch analysis

Carlton

2019

Strabismus

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The Child Amblyopia Treatment Questionnaire (CAT-Q L methodological approach. Interviews with children with amblyopia identified items (questions) and response levels to be tested in a draft questionnaire consisting of 11 items (sad, feeling on face, hurt, doing schoolwork, cross, how other children treat you, doing things, worried, upset with family, playing with friends, happy). This study describes the refinement of the descriptive system for the CAT-QoL instrument using the application of Rasch analysis. Methods A multi-centre pilot study was conducted, and data collected from 342 participants. Participants were asked to self-complete the appropriate treatment version of the CAT-QoL questionnaire Socio-demographic and clinical data was collected by the clinician using a standardised A R to refine the questionnaire. Rasch was used to examine response categories and collapse item response levels, identify poorly performing items, and explore local dependency of items. Results A total of 331 subjects were included in the study sample, however only 315 were accepted into the RUMM program as a number of subjects had missing questions responses on the CAT-QoL. RUMM also excluded a further 41 subjects as these demonstrated extreme responses. Disordered response categories were found for each item, requiring adjacent response levels to be combined. This was applied to all items, and the model fit was reexamined. Two items were found to have poor fit (cross and happy) and were removed from the measure and the model fit was reexamined. No statistically significant differential item functioning (DIF) was found for any item, using person factors of age, sex, or general health. Two items showed some dependency (worried and upset with family), and the poorer fitting item was subsequently 3 removed (upset with family). This resulted in a refined CAT-QoL instrument that consists of 8items, each with 3-level response scales. Conclusion The refined CAT-QoL instrument includes the following items: sad, feeling on face, hurt, doing work at school, how other children treat you, doing things, worried, and playing with friends). The CAT-QoL can be Rasch scored, with a range of 0-16 where a greater value indicates a worse quality of life (or greater impact of treatment on the individual). The CAT-QoL may be useful in determining how amblyopia treatment affects children, and offers an alternative to generic patient reported outcome measures.

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Development of a Keratoconus-Specific Questionnaire Using Rasch Analysis

Abstract: The 29-item KORQ was a psychometrically robust and valid instrument to assess the impact of keratoconus on activity limitation and symptoms.

Cited by 33 publications

References 36 publications

<p>Development and Validation of the “Keratoconus End-Points Assessment Questionnaire” (KEPAQ), a Disease-Specific Instrument for Evaluating Subjective Emotional Distress and Visual Function Through Rasch Analysis</p>

<p>Development and Validation of the “Keratoconus End-Points Assessment Questionnaire” (KEPAQ), a Disease-Specific Instrument for Evaluating Subjective Emotional Distress and Visual Function Through Rasch Analysis</p>

Exploring the potential for item banking in assessing quality of life for evaluating adolescent health interventions

Refinement of the Child Amblyopia Treatment Questionnaire (CAT-QoL) using Rasch analysis

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