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

Kepa Balparda,1,2 Tatiana Herrera-Chalarca,3 Laura Andrea Silva-Quintero,4 Sneider Alexander Torres-Soto,4 Claudia Marcela Vanegas-Ramírez5 1Department of Cornea and Refractive Surgery, Black Mammoth Surgical, Medellín, Colombia; 2Universidad de Valladolid, Valladolid, Spain; 3...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Balparda K, Herrera-Chalarca T, Silva-Quintero LA, Torres-Soto SA, Vanegas-Ramírez CM
Formato: article
Lenguaje:EN
Publicado: Dove Medical Press 2020
Materias:
Acceso en línea:https://doaj.org/article/03d9b16a158a47f3b8493e53a71926c6
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:doaj.org-article:03d9b16a158a47f3b8493e53a71926c6
record_format dspace
spelling oai:doaj.org-article:03d9b16a158a47f3b8493e53a71926c62021-12-02T12:08:07ZDevelopment and Validation of the “Keratoconus End-Points Assessment Questionnaire” (KEPAQ), a Disease-Specific Instrument for Evaluating Subjective Emotional Distress and Visual Function Through Rasch Analysis1177-5483https://doaj.org/article/03d9b16a158a47f3b8493e53a71926c62020-05-01T00:00:00Zhttps://www.dovepress.com/development-and-validation-of-the-ldquokeratoconus-end-points-assessme-peer-reviewed-article-OPTHhttps://doaj.org/toc/1177-5483Kepa Balparda,1,2 Tatiana Herrera-Chalarca,3 Laura Andrea Silva-Quintero,4 Sneider Alexander Torres-Soto,4 Claudia Marcela Vanegas-Ramírez5 1Department of Cornea and Refractive Surgery, Black Mammoth Surgical, Medellín, Colombia; 2Universidad de Valladolid, Valladolid, Spain; 3Department of Clinical Research, Black Mammoth Surgical, Medellín, Colombia; 4General Physician, Medicarte, Medellín, Colombia; 5Department of Ophthalmology, Universidad Pontificia Bolivariana, Medellín, ColombiaCorrespondence: Kepa BalpardaClínica de Oftalmología Sandiego, Carrera 43 #29– 35, Consultorio 712, Medellín, ColombiaEmail kb@kepabalparda.comBackground: 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, 20-question 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.Keywords: keratoconus, quality of life, vision ocularBalparda KHerrera-Chalarca TSilva-Quintero LATorres-Soto SAVanegas-Ramírez CMDove Medical Pressarticlekeratoconusquality of lifevision ocularOphthalmologyRE1-994ENClinical Ophthalmology, Vol Volume 14, Pp 1287-1296 (2020)
institution DOAJ
collection DOAJ
language EN
topic keratoconus
quality of life
vision ocular
Ophthalmology
RE1-994
spellingShingle keratoconus
quality of life
vision ocular
Ophthalmology
RE1-994
Balparda K
Herrera-Chalarca T
Silva-Quintero LA
Torres-Soto SA
Vanegas-Ramírez CM
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
description Kepa Balparda,1,2 Tatiana Herrera-Chalarca,3 Laura Andrea Silva-Quintero,4 Sneider Alexander Torres-Soto,4 Claudia Marcela Vanegas-Ramírez5 1Department of Cornea and Refractive Surgery, Black Mammoth Surgical, Medellín, Colombia; 2Universidad de Valladolid, Valladolid, Spain; 3Department of Clinical Research, Black Mammoth Surgical, Medellín, Colombia; 4General Physician, Medicarte, Medellín, Colombia; 5Department of Ophthalmology, Universidad Pontificia Bolivariana, Medellín, ColombiaCorrespondence: Kepa BalpardaClínica de Oftalmología Sandiego, Carrera 43 #29– 35, Consultorio 712, Medellín, ColombiaEmail kb@kepabalparda.comBackground: 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, 20-question 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.Keywords: keratoconus, quality of life, vision ocular
format article
author Balparda K
Herrera-Chalarca T
Silva-Quintero LA
Torres-Soto SA
Vanegas-Ramírez CM
author_facet Balparda K
Herrera-Chalarca T
Silva-Quintero LA
Torres-Soto SA
Vanegas-Ramírez CM
author_sort Balparda K
title 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
title_short 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
title_full 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
title_fullStr 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
title_full_unstemmed 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
title_sort 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
publisher Dove Medical Press
publishDate 2020
url https://doaj.org/article/03d9b16a158a47f3b8493e53a71926c6
work_keys_str_mv AT balpardak developmentandvalidationoftheldquokeratoconusendpointsassessmentquestionnairerdquokepaqadiseasespecificinstrumentforevaluatingsubjectiveemotionaldistressandvisualfunctionthroughraschanalysis
AT herrerachalarcat developmentandvalidationoftheldquokeratoconusendpointsassessmentquestionnairerdquokepaqadiseasespecificinstrumentforevaluatingsubjectiveemotionaldistressandvisualfunctionthroughraschanalysis
AT silvaquinterola developmentandvalidationoftheldquokeratoconusendpointsassessmentquestionnairerdquokepaqadiseasespecificinstrumentforevaluatingsubjectiveemotionaldistressandvisualfunctionthroughraschanalysis
AT torressotosa developmentandvalidationoftheldquokeratoconusendpointsassessmentquestionnairerdquokepaqadiseasespecificinstrumentforevaluatingsubjectiveemotionaldistressandvisualfunctionthroughraschanalysis
AT vanegasramirezcm developmentandvalidationoftheldquokeratoconusendpointsassessmentquestionnairerdquokepaqadiseasespecificinstrumentforevaluatingsubjectiveemotionaldistressandvisualfunctionthroughraschanalysis
_version_ 1718394670974763008