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PRECIS In this study, huge time delay was observed between first primary congenital glaucoma (PCG) symptom recognition by parents to ophthalmological diagnosis and this delay was unchanged over time. Bilateral affliction and mean presenting intraocular pressure (IOP) remained unaltered. PURPOSE To compare the trends in presentation of patients with PCG over 3 different time periods at 10-year intervals (1998, 2008, and 2018) managed by a single surgeon at one of the largest tertiary eye care centers in South India. METHODS Retrospective analysis of 313 eyes of 172 patients diagnosed to have PCG and treated at the L V Prasad Eye Institute (LVPEI) between January and December of the 3 specified years. Data collected included age at symptom recognition and at presentation, sex, affected eye, signs and symptoms, time between onset of symptoms and diagnosis (diagnostic delay), corneal clarity, and IOP. RESULTS Of the 172 patients, 48 (27.9%), 76 (44.2%), and 48 (27.9%) belonged to 1998, 2008, and 2018, respectively. Bilateral affliction (79% to 84%) was common and there was no sex predilection. The median age at recognition of first symptoms by caregivers/parents was 1 day (interquartile range, 1 to 30), and at diagnosis was 120 days (interquartile range, 30 to 378). Overall, presentation to LVPEI was delayed by >3 months in 80 (46.5%) children, and there was no statistically significant difference in the duration of delay over time (P=0.13). There was no significant difference in the mean presenting IOP over time (P>0.05). CONCLUSIONS We provide unique single center-based information of trends in the presentation of patients with PCG over 3 decades. Diagnostic delay was common, and a large number of characteristics of patients with PCG in South India have remained unchanged, particularly, age at onset and at diagnosis and laterality.

To validate the Indian-translated Impact of Vision Impairment for Children (IVI_C), a vision-related quality of life (VRQoL) instrument, and to investigate the effect of sociodemographic and ocular characteristics on VRQoL.The 24-item IVI_C was administered face to face to 221 children with vision impairment (VI) (mean age, 12.6 years; male, 68%) referred to the Vision Rehabilitation Centres. Rasch analysis was used to investigate the IVI_C for key indices such as measurement precision as measured by person separation (minimum recommended value, 2.0), unidimensionality (i.e., whether all the items contribute toward measurement of a single underlying construct as assessed by item fit and principal component analysis of residuals), targeting of items to participants' VRQoL (i.e., matching of item difficulty to participant ability; ideal targeting,1.0 logits). Univariate analysis was performed to determine if the person scores of IVI_C were significantly different across participant subgroups stratified by sociodemographic and ocular characteristics, including the severity of VI.The IVI_C showed misfit to the model and lacked unidimensionality. Principal component analysis confirmed the presence of an additional construct, mobility, but it did not possess adequate person separation when assessed individually. Deleting the mobility-related items restored unidimensionality, but additional items misfit, necessitating item reduction. Finally, a 17-item IVI_C possessed good measurement precision (person separation, 2.04), was unidimensional (albeit not purely), and consisted of items that fit the Rasch model and were well targeted to the participants' VRQoL (targeting 0.76 logits). There was no statistically significant difference in the VRQoL across subgroups stratified by age, sex, type of school, cause of VI, duration of vision loss, and severity of VI (p0.05 for all).The revised 17-item IVI_C is shorter and has better psychometric properties than the original version in school-aged children with VI in India, and the responses are unrelated to sociodemographic and clinical variables. Although it has the potential for use in cross-sectional and outcomes research in children with VI, caution should be exercised while interpreting the 17-item IVI_C scores given the presence of slight multidimensionality.

PURPOSE Visual impairment (VI) negatively affects quality of life (QoL). Utilities represent a way of measuring the QoL impact associated with a particular health state, like VI, and are also useful in economic evaluations of health care interventions. Utilities can be determined either directly or indirectly. Here we determine whether the Vision and Quality of Life Index, VisQoL (indirect approach), is acceptable to use in patients with VI in an urban setting in South India; whether the VisQoL utility values, derived from an Australian sample of both visually impaired and normally sighted participants, demonstrate agreement (if any) with direct utilities, determined by time trade-off (TTO), from visually impaired South Indian patients; and determine the relationship between utilities and self-reported visual disability. METHODS Three hundred forty-nine adults with VI were administered the two-item TTO item, six-item VisQoL, and the 16-item Andhra Pradesh Eye Disease-Visual Function Questionnaire (APEDS-VFQ) in a face-to-face interview. The VisQoL utilities were derived from the utility scoring algorithm. Rasch-scaled scores of the APEDS-VFQ were obtained using the conversion scores sheets. Agreement between TTO and utilities VisQoL was assessed using the Bland-Altman method. RESULTS All participants (response rate, 100%) completed the VisQoL as compared with 72% for the TTO. There was no statistically significant difference in the mean utilities from the two methods (0.65 ± 0.31 by TTO vs. 0.66 ± 0.27 by VisQoL, p = 0.67). However, the 95% limits of agreement on the Bland-Altman plot were wide (-0.65, 0.67), implying a lack of agreement between the methods. The VisQoL relates relatively strongly with APEDS-VFQ as compared with TTO (TTO vs. APEDS-VFQ, r = -0.23, VisQoL vs. APEDS-VFQ, r = -0.66, z = -6.70; p < 0.001 for both). Older participants, female, and those with less than 12 years of education had lower utilities. CONCLUSIONS The direct (TTO) and indirect (VisQoL) methods of utility evaluation tend to disagree in our patients with VI. Given the high completion rates of the VisQoL as compared with the TTO, the VisQoL may be a suitable alternative for utility assessment in an Indian population.

PURPOSE: To explore the psychometric properties of the revised Olweus Bully/Victim Questionnaire (OBVQ) in children with visual impairment (VI) using Rasch analysis. METHODS: One hundred fifty Indian children with VI between 8 and 16 years (mean age, 11.6 years; 69% male; mean acuity in the better eye of 0.80 logMAR [Snellen, 20/126]) were administered the revised OBVQ. The 40-item revised OBVQ was developed to assess victimization (i.e., being bullied) and bullying (bullying others) in normally sighted schoolchildren. Only 16 items are used for Rasch analysis and are divided into two parts: I (victimization, eight items) and II (bullying others, eight items). Separate Rasch analysis was conducted for both parts, and the psychometric properties investigated included behavior of rating scale, extent to which the items measured a single construct (unidimensionality by fit statistics and principal component analysis [PCA] of residuals); ability to discriminate among participants' victimization and bullying behaviors (measurement precision as assessed by person separation reliability [PSR] minimum recommended value, 0.80); and targeting of items to participants' victimization and bullying. RESULTS: Response categories were misused for both parts I and II, which required repair before further analysis. Measurement precision was inadequate for both parts (PSR, 0.64 for part I and 0.19 for part II), indicating poor discriminatory ability. All items fit the Rasch model well in part I, indicating unidimensionality that was further confirmed using PCA of residuals. However, an item misfit in part II that required deletion following which the remaining items fit and PCA of residuals also supported unidimensionality. Targeting was -0.58 logits for part I, indicating that the items were matched well with the participants' victimization. By comparison, targeting was suboptimal for part II (-1.97 logits). CONCLUSIONS: In its current state, the revised OBVQ is not a valid psychometric instrument to assess victimization and bullying among children with VI. Language: en

Purpose To test the assumption that the National Eye Institute Visual Function Questionnaire (NEI VFQ) measures visual functioning, assess the validity of its subscales, and, if flawed, revise the questionnaire and derive a shortened version with sound psychometric properties. Setting Flinders Medical Centre, Adelaide, Australia. Methods Patients from the cataract surgery waiting list self-administered and completed the 39-item NEI VFQ (NEI VFQ-39). Rasch analysis was applied, and the psychometric performance of the entire questionnaire and each subscale was tested. Instrument revision was performed in the context of Rasch analysis statistics. Results Five hundred thirty-six patients (mean age 73.8 years) completed the questionnaire. Response categories for 2 question types were not used as intended so dysfunctional categories were combined. The NEI VFQ-39 and the 25-item version (NEI VFQ-25) had good precision but evidence of multidimensionality (more than 1 construct in 1 score), questions that did not fit the construct, suboptimum targeting of item difficulty to person ability, and dysfunctional subscales (8 NEI VFQ-39; 12 NEI VFQ-25). Questions could be reorganized into 2 constructs (a visual functioning scale and a socioemotional scale) that, after misfitting questions were removed, gave valid measurement of each construct and preserved 3 subscales. Removing redundancy from these long-form subscales yielded valid short-form scales. Conclusions Several NEI VFQ subscales were not psychometrically sound; as an overall measure, it is flawed by multidimensionality. This was repaired by segregation into visual functioning and socioemotional scales. Valid long and short forms of the scales could enhance application of the questionnaire. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Purpose To examine the psychometric properties of the Visual Activities Questionnaire (VAQ) and each of its subscales in a modern cataract population using Rasch analysis and if flawed, to revise the VAQ and create a valid measure that maximizes its measurement properties. Setting Flinders Eye Centre, Flinders Medical Centre, Adelaide, Australia. Methods Patients with cataract in 1 or both eyes drawn from the surgical waiting list were mailed the 33-item VAQ for self-administration. The following were examined for the entire questionnaire and each subscale: whether items measured a single construct (unidimensionality), the behavior of response categories, the ability to differentiate between patients' visual abilities (person separation), matching of item difficulty to participant ability (targeting), and whether items function similarly across subgroups of participants (differential item functioning [DIF]). Results The VAQ was completed by 561 patients. Response categories were used as intended. The VAQ discriminated the visual ability of the population (person separation, 4.88) but had suboptimum targeting, misfitting items, significant multidimensionality, DIF, and 4 dysfunctional subscales. Elimination of items causing multidimensionality resulted in a reduced 13-item VAQ that met all validity criteria for satisfactory instrument performance. Only 1 valid subscale (peripheral vision) could be preserved in the 13-item VAQ. Conclusions The VAQ in its native form was multidimensional and contained subscales with poor psychometric properties. The revised unidimensional 13-item VAQ was more appropriate for application in cataract outcomes assessment. Ideally, more items should be included to improve the targeting of item difficulty to more able cataract patients.

Purpose. To validate visual disability questionnaire (VDQ) in patients with low vision in India, and explore whether the two latent traits “importance” and “difficulty” associated with performance of daily activities are valid and independent constructs. Methods. The VDQ consisting of 25 items was administered verbally to 137 subjects with low vision aged 16 to 89 years. Responses for each item were rated for importance and difficulty using a 5-category Likert scale. Rasch analysis was used to estimate interval measures of response ratings. Results. Subjects could discriminate only three response categories for importance and difficulty. Content validity was demonstrated by good separation indices for importance (4.24 and 2.59 for the item and person parameters, respectively) and difficulty ratings (7.64 and 3.33, respectively). High reliability scores were recorded for importance (0.95 and 0.87) and difficulty ratings (0.98 and 0.92). The most important items were “grooming” (1.15 logits) and “reading newspaper” (0.97 logits). Although “threading a needle” was the least important item (2.79 logits), it was the most difficult task (3.13 logits). The least difficult item was moving around in familiar places (2.51 logits). A poor correlation was observed between the item measures (r 0.19, p 0.34) and also between person measures (r 0.18, p 0.03) of importance and difficulty. Conclusions. The VDQ is a valid questionnaire with importance and difficulty ratings found to be independent constructs. This questionnaire could be used to prioritize the goals for rehabilitation intervention in patients with low vision. (Optom Vis Sci 2009;86:E826–E835)

AIM—To evaluate the efficacy of intravitreal dexamethasone co-administered with intravitreal antibiotics along with vitrectomy in the management of exogenous bacterial endophthalmitis. METHODS—In a prospective randomised clinical trial, 63 patients (63 eyes) with suspected bacterial endophthalmitis (postoperative and post-traumatic) were treated with vitrectomy and intravitreal antibiotics and randomised to intravitreal dexamethasone (IOAB with = 29 eyes) and no dexamethasone (IOAB without = 34 eyes). Inflammation score (IS) and visual acuity were measured by two masked observers before surgery, and at 1, 4, and 12 weeks after surgery in both the groups. RESULTS—There was significant reduction (p