The Importance of Rating Scale Design in the Measurement of Patient-Reported Outcomes Using Questionnaires or Item Banks

This article is made available with the permission of the publisher, Association for Research in Vision and OphthalmologyPurpose.: To investigate the effect of rating scale designs (question formats and response categories) on item difficulty calibrations and assess the impact that rating scale differences have on overall vision-related activity limitation (VRAL) scores. Methods.: Sixteen existing patient-reported outcome instruments (PROs) suitable for cataract assessment, with different rating scales, were self-administered by patients on a cataract surgery waiting list. A total of 226 VRAL items from these PROs in their native rating scales were included in an item bank and calibrated using Rasch analysis. Fifteen item/content areas (e.g., reading newspapers) appearing in at least three different PROs were identified. Within each content area, item calibrations were compared and their range calculated. Similarly, five PROs having at least three items in common with the Visual Function (VF-14) were compared in terms of average item measures. Results.: A total of 614 patients (mean age ± SD, 74.1 ± 9.4 years) participated. Items with the same content varied in their calibration by as much as two logits; “reading the small print” had the largest range (1.99 logits) followed by “watching TV” (1.60). Compared with the VF-14 (0.00 logits), the rating scale of the Visual Disability Assessment (1.13 logits) produced the most difficult items and the Cataract Symptom Scale (0.24 logits) produced the least difficult items. The VRAL item bank was suboptimally targeted to the ability level of the participants (2.00 logits). Conclusions.: Rating scale designs have a significant effect on item calibrations. Therefore, constructing item banks from existing items in their native formats carries risks to face validity and transmission of problems inherent in existing instruments, such as poor targeting

Young adults with vision impairment in India: Loneliness and social networks

Purpose To examine the prevalence of loneliness and associated factors in young adults with vision impairment (VI), including quality of life (QoL) in India. Methods Two hundred and three VI young adults (18–35 years) and 219 age‐matched non‐VI (controls) adults completed the loneliness scale, WHOQOL‐BREF, Social Network Index (SNI) (network diversity, people in network size and number of embedded network subscales) and questions regarding sociodemographic characteristics and independent mobility. Rasch analysis was used to validate the questionnaires and interval‐level scores were generated. Generalised linear models were used to estimate independent associations of sociodemographic factors, VI characteristics, social networks and QoL with loneliness. Results The prevalence of moderate and severe loneliness in the VI group was 10% (95% CI: 6.5, 15.4) and 4.4% (95% CI: 2.0, 8.2), respectively, and higher than that of controls. The VI group had a worse loneliness score than controls (−1.66 ± 2.25 vs. −2.13 ± 1.85 logits; p = 0.03). Those with ≤12 years and >12 years of education had loneliness scores of −1.58 ± 2.45 and −1.82 ± 1.99 logits, respectively (p = 0.01). Compared with controls, the VI group reported fewer extended family members, neighbours and friends leading to significantly smaller networks and network diversity (all p < 0.001). Loneliness scores demonstrated a significant correlation with only two SNI subscales for both groups: people in network size (r = −0.28 for VI; r = −0.30 for non‐VI; p < 0.001 for both) and number of embedded networks (r = −0.22 for VI; r = −0.21 for non‐VI; p = 0.002 for both). Both education (β = 0.45; p = 0.04) and QoL (β = −0.27, p = 0.02) were predictors of loneliness. Conclusions Loneliness was commonly experienced by young VI adults and was higher among those with lower levels of education. Loneliness decreased with the presence of a larger number of people in network, suggesting that interventions to increase social activity and participation may be valuable in young VI adults

One size doesn’t fit all: time to revisit patient-reported outcome measures (PROMs) in paediatric ophthalmology?

The purpose of this article is to summarise methodological challenges and opportunities in the development and application of patient reported outcome measures (PROMs) for the rare and complex population of children with visually impairing disorders. Following a literature review on development and application of PROMs in children in general, including those with disabilities and or/chronic condition, we identified and discuss here 5 key issues that are specific to children with visual impairment: (1) the conflation between theoretically distinct vision-related constructs and outcomes, (2) the importance of developmentally appropriate approaches to design and application of PROMs, (3) feasibility of standard questionnaire formats and administration for children with different levels of visual impairment, (4) feasibility and nature of self-reporting by visually impaired children, and (5) epidemiological, statistical and ethical considerations. There is an established need for vision-specific age-appropriate PROMs for use in paediatric ophthalmology, but there are significant practical and methodological challenges in developing and applying appropriate measures. Further understanding of the characteristics and needs of visually impaired children as questionnaire respondents is necessary for development of quality PROMs and their meaningful application in clinical practice and research

Effect of yield potential, drought escape and drought tolerance on yield of pearl millet (Pennisetum glaucum) in different stress environments

An experiment was conducted during the rainy season of 1988 and 1989 and the dry season of 1989 and 1990 to study the effectof yield potential, drought escape and tolerance on the grain yield of pearl millet [Pennisetum glaucum (L.) R. Br. emend.Stuntz] under stress. Different types of drought and heat stress occurred, viz moderate and severe post-flowering drought andsevcrepre-flowecing drought, combined with either high or low temperature during grain filling. Yield potential was onlyrelated to yield under stress when pre-flowering drought was combined with low temperatures. Escape was the predominantfactor if temperature was high, except if combined with pre-flowering drought, in which case tolerance became more important.These results show that for stressed environments, selection for yield potential is of limited use. The importance of escapeand tolerance, however, depends on the timing and intensity of stress occurrence. If pearl millet-growing regions can becharaoterized based on occurrence of abiotic stress, breeders can select more efficiently for plant traits that enhancestress adaptation in specific target environment

Cross-cultural validation of the functional vision questionnaire for children and young people (FVQ_CYP) with visual impairment in the Dutch population: challenges and opportunities

BACKGROUND:To assess cross-cultural validity between Dutch and English versions of the FVQ_CYP, a patient-reported outcome measure developed in the United Kingdom (UK) for children and adolescents with (severe) visual impairment or blindness (VI for brevity) to measure functional vision. METHODS:The 36-item FVQ_CYP was translated and adapted into Dutch using standard guidelines. The questionnaire was administered to Dutch children and adolescents aged 7-17 years (N = 253) with impaired vision (no restrictions regarding acuity). Data were compared to existing UK data of children and adolescents aged 10-15 years (N = 91) with VI (acuity LogMar worse than 0.48). As with the original UK FVQ_CYP validation, a rating scale model (RSM) was applied to the Dutch data. RESULTS:Minor adaptations were needed in translation-rounds. Significant differences in item responses were found between the Dutch and UK data. Item response theory assumptions were met, but fit to the RSM was unsatisfactory. Therefore, psychometric properties of the Dutch FVQ_CYP were analysed irrespective of the original model and criteria used. A graded response model led to the removal of 12 items due to missing data, low information, overlapping content and limited relevance to Dutch children. Fit indices for the remaining 24 items were adequate. CONCLUSIONS:Differences in population characteristics, distribution of responses, non-invariance at the model level and small sample sizes challenged the cross-cultural validation process. However, the Dutch adapted FVQ_CYP showed high measurement precision and broad coverage of items measuring children's functional vision. The underlying reasons for differences between countries in instrument performance are discussed with implications for future studies

Angle closure glaucoma in nanophthalmos and pigmentary retinal dystrophy : a rare syndrome.

The simultaneous occurrence of nanophthalmos, angle closure glaucoma and pigmentary retinal dystrophy documented in the present case represents a rare syndrome

Life in lockdown: impact of COVID‐19 lockdown measures on the lives of visually impaired school‐age children and their families in India

Purpose: The COVID-19 outbreak has adversely impacted all societal domains, including education. Home confinement, school closures, and distance learning impacted children, teachers, and parents’ lives worldwide. In this study, we aimed to examine the impact of COVID-19 lockdown on the lives, including education, of school-age children with vision impairment (VI) and their parents in India. Methods: Primary and secondary school children with VI were recruited from the Institute for Vision Rehabilitation, L V Prasad Eye Institute, Hyderabad, India. A qualitative research methodology, utilising a self-constructed questionnaire with open and closed questions and stem and leaf design was employed to explore the experiences of school closure and its impact on education, and attending online classes during the COVID-19 lockdown. Textual data from responses to the questions were analysed using content analysis to identify themes pertinent to the cohort studied. Results: Forty-eight child-parent dyads were included. Median age of children was 10 years (range, 7-19 years) and 60% were male. Inherited retinal disorders were the major cause of VI (40%). Best-spectacle corrected visual acuity (better eye) ranged from 6/12 (0.3 logMAR) to 6/750 (2.09 logMAR). Six major themes were identified: (1) accessibility of technology (online learning and technology); (2) parental beliefs/concerns (harmful effects of technology, prioritization of normally sighted children, online classes considered a distraction); (3) support (peers, parents, teachers, private tuition); (4) socialization and physical activity, (5) socioeconomic status, and (6) near vision. Conclusions: Our study provides an understanding of the adverse impact of the lockdown on the lives of children with VI and their parents, especially related to education in India. The study identified critical factors that affect online learning and the participation of children with VI in these sessions. Policy makers and educators should implement effective measures for supporting online classes

Social media use and vision impairment in adults between the ages of 18 and 35 years in India

SIGNIFICANCE Social media is used by >4.48 billion people worldwide. Despite its popularity, vision-impaired individuals struggle to use social media given visual inaccessibility of content and lack of access to Internet/Wireless-Fidelity–enabled devices. Our study explores visually impaired adult's use of social media in comparison to a control group. PURPOSE This study aimed to report the demographic profile and patterns of social media use among adults with vision impairment (VI) aged 18 to 35 years and compare it with an age-matched normally sighted group in India. In addition, we explored barriers to use of social media among adults with VI. METHODS Vision-impaired and normally sighted adults (controls) aged 18 to 35 years at L V Prasad Eye Institute, Hyderabad, India, answered a questionnaire about social media use (e.g., platform used). RESULTS Four hundred twenty-two individuals (201 VI, 221 controls) participated. Normally sighted adults (98%) used social media more than the VI group (81%; p<0.001). Vision-impaired users were predominantly male (85%) and unemployed (57%; p<0.00001 for both). There was no significant difference in educational level between groups (p=0.17). Smartphones were the most popular device used (VI, 161 [99%]; control, 206 [95%]), with tablet PC/iPad being the least popular (VI, 5 [3%]; control, 12 [6%]). Adults with VI and controls commonly used WhatsApp as communication platforms, and Facebook and Twitter as networking platforms. Approximately one-third of individuals across both social media user groups reported barriers to use (VI, 48 [30%]; control, 74 [34%]; p<0.001). Vision-impaired individuals cited accessibility issues of having to rely on audio over vision to navigate social media, whereas controls reported having to share a phone. CONCLUSIONS The proportion of social media usage among VI adults is high (81%) and is substantially higher than the 33% reported in the general Indian population. Vision-impaired adults who used social media were male with moderate VI and were less likely to be employed compared with controls

Calibrating the Impact of Vision Impairment (IVI): Creation of a Sample-Independent Visual Function Measure for Patient-Centered Outcomes Research

Purpose: Provide item calibrations estimated for the Impact of Vision Impairment (IVI) questionnaire by pooling data from several studies of people with vision impairment (VI) representing a variety of countries and causes of VI. Methods: Eight data sets from six principal investigators representing responses to IVI items from 2867 VI patients were pooled for analysis. Eligible patients were 18 years or older and from Australia, India, and the United States. Rasch analysis, using the Andrich Rating Scale Model (Winsteps version 3.65), was performed on preintervention IVI responses to estimate item and person measures, reliability coefficients, and response category thresholds. Differential item functioning (DIF) analysis and analysis of variance (ANOVA) were used to examine the effects different data sets and covariates on item estimates. Results: Patient age range was 18 to 103 years (median 62 years); 55% were male. Visual acuity ranged from 20/20 to no light perception and primary diagnosis was macular degeneration in 29% of patients. Item measure estimates showed good separation reliability (R 2 = 0.99). DIF magnitude did not preclude use of all IVI-28 data. ANOVA showed VA (P < 0.001) and gender (P < 0.002) were predictors of visual ability. Conclusions: Analysis from pooled data support the provision of calibrated IVI item measures for researchers and clinicians to use, thus better enabling direct comparisons of patients with VI. Translational Relevance: Validity testing of the IVI show that we can combine disparate data sets of patient responses to calibrate item measures and response category thresholds, and provide to others for use in comparing patients across clinical trials and on an individual basis