ABSTRACT
To translate the the Utah Photophobia Symptom Impact Scale-12 questionnaire into Persian and assess the psychometric aspects to check its validity and reliability based on the Rasch modelling method. Translation and cultural adjustment of the English language UPSIS-12 questionnaire to Persian was undertaken. A total of 61 patients with complaints of photophobia participated in evaluating validity and reliability aspects. All the participants were asked to complete the Persian translation of the UPSIS-12 questionnaire. Rasch analyses of the survey items were conducted using WINSTEPS. All items fit the Rasch model. Point-measure correlation values varied from 0.41 to 0.77, providing a preliminary indication of adequate construct validity. All factor loadings were found more than 0.4. All items obtained infit and outfit mean square (MnSq) values of < 2.0. All participants except 5 had normal outfit values. Patients' abilities relative to the items' difficulty were analysed. Item difficulty was estimated and item characteristic curves were included. Sufficient unidimensionality, hierarchical order, and equal interval scoring were obtained. In conclusion, the Persian UPSIS-10 questionnaire has excellent psychometric properties and it will be valuable in both clinical practice and research. It will help Persian practitioners to assess their patients' photophobia.
ABSTRACT
CLINICAL RELEVANCE: Evaluating factors affecting corneal higher-order aberration component has a very important role in interpreting the characteristics of the formed image on the retina. BACKGROUND: To determine the relationship between ocular biometric components and corneal higher-order aberrations in an elderly population. METHODS: This report is related to a subsample of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on individuals aged 60 years and above in Tehran city, Iran using multistage stratified random cluster sampling. All study participants underwent ocular examinations including visual acuity measurement, refraction and slit-lamp biomicroscopy. Anterior segment imaging and corneal aberrometry were performed using Pentacam AXL. RESULTS: In the present study, 644 eyes of 415 individuals (56.9% female) with mean age of 66.36 ± 4.70 years were evaluated. According to a multiple generalised estimating equation model, the root mean square of total higher-order aberrations was related to age (ß = 0.081, p = 0.002), crystalline lens thickness (ß = 0.08, p < 0.001), and corneal diameter (ß = -0.04, p = 0.014). The root mean square of total coma aberration was directly related to the female sex (ß = 0.02, p = 0.05), and crystalline lens thickness (ß = 0.06, p < 0.001). There was a direct relationship between the root mean square of third- and fourth-order higher-order aberrations and crystalline lens thickness (p < 0.001). Spherical aberration was directly related to the male sex (ß = -0.02, p = 0.004), axial length (ß = 0.05, p < 0.001) and central corneal thickness (ß = 0.001, p = 0.025), and was inversely related to anterior chamber depth (ß = -0.07, p = 0.031) and crystalline lens thickness (ß = -0.25, p < 0.001). CONCLUSION: Ocular biometric components are related to corneal aberrations in the elderly. These factors need to be considered in respect of medical and surgical procedures required for the elderly.