The VF-14 index of functional visual impairment in candidates for a corneal graft

Psychometric Validity of the Visual Function Index in Leber Hereditary Optic Neuropathy

Purpose

The purpose of this study was to determine the psychometric validity of the Visual Function Index (VF-14) for use by patients with Leber hereditary optic neuropathy (LHON).

Methods

Rasch analysis was conducted in two stages using data for 196 individuals (74.5% male) carrying one of the three primary LHON mutations and affected by vision loss. In stage 1, scale unidimensionality, scale-to-sample targeting, response category threshold ordering, item fit statistics, local dependency, and reliability were assessed. In stage 2, iterative post-hoc revisions of the VF-14 structure (VF-14R) were applied and psychometrically re-evaluated.

Results

Issues identified with the VF-14 included disordered response thresholds (12/14 items), local dependency (10/91 pairwise dependencies), and evidence of multidimensionality. However, the distribution of person estimates and item thresholds were fairly well matched, only one item showed misfit to the Rasch model, and there was good reliability (Person Separation Index 0.84). Rasch-informed VF-14 revisions included removing both driving items and the misfitting sports item, rescoring response options across all items by merging two response categories, and accounting for the dependency between two reading items. The VF-14R demonstrated improved psychometric validity.

Conclusions

Clinicians and researchers using the VF-14 with LHON patients should be aware of its limitations. Compared to the original version, the proposed Rasch-based structure of the VF-14R appears to offer improved psychometric performance and interpretation of vision-related activity limitation.

Translational Relevance

The original version of the VF-14 exhibits several limitations that undermines its psychometric validity as a patient-reported outcome measure for patients with LHON.

Assessment of patient-reported outcome measures used in corneal transplantation: a systematic review

The aim of this study was to review all the articles that have implemented patient-reported outcome measures (PROMs) to evaluate the quality of life (QoL) in corneal transplantation and discuss quality assessments of the PROMs. An extensive literature review was undertaken to identify all the studies that used PROMs to assess the QoL in corneal transplantation. Non-original or review articles, articles on other subject area and articles on cost-effectiveness/utility without PROM data/results were excluded. Each PROM was assessed against the following criteria: content development (item identification and item selection), psychometric properties, validity, reliability, and responsiveness. 425 articles were identified of which 35 articles were included in the final review. PROMs in corneal transplantation were used to (a) evaluate the QoL after surgery, (b) compare the QoL scores between different surgical techniques and (c) determine the relationship between QoL and objective measures such as visual acuity, visual field and stereoacuity. A total of 17 PROMs were used to assess QoL in corneal transplantation. Whilst this search did not produce any PROMs that were specifically designed to assess corneal transplantation, most studies were found to have employed the National Eye Institute Visual Function Questionnaire 25 (NEI VFQ 25). The Visual Function Index 14 (VF 14) performed better in the present quality assessment criteria compared to other PROMs, however, the NEI VFQ 25 and the VF 14 PROMs were not specifically developed for corneal transplantation and therefore the QoL assessment made using these PROMs may be incomplete. As improvements in various forms of lamellar transplantation surgery techniques such as UT-DSAEK and FT-DSAEK have resulted in better visual outcomes, improved graft survival and reduced complications, a corneal transplantation specific PROM will be useful in clinical settings to compare the outcomes of different surgical techniques from the patient perspective.

The Association of the Prevalence of Depression in Type 2 Diabetes Mellitus with Visual-Related Quality of Life and Social Support

AIM

To report the prevalence of depression and its association with vision-related quality of life and social support in a type 2 diabetes mellitus (T2DM) population.

METHODS

Patients were recruited from a community-based study, Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT), conducted between July 2012 and May 2013 in China. Depression was assessed using the Centre for Epidemiological Studies Depression Scale (CES-D). Vision-related quality of life was evaluated using the Visual Function Questionnaire-25 (VFQ-25). Social support was captured with the Social Support Rating Scale (SSRS). Generalized linear models were used to estimate the individual and joint association of VFQ-25 composite score (VFQCS) and SSRS score (SSRSS) with depression.

RESULTS

A total of 1618 subjects (60.9% female) aged 61.69 ± 8.72 years in an urban district of Jiangjun Street, Fushun City, Liaoning province, Northeast China from July 2012 to May 2013 were recruited, of which, 23.36% (95% CI: 21.30-25.42%) were identified with depression. Every 14.1 increase in VFQ-25 composite score decreased the risk of depression by half (OR = 0.5; 95% CI: 0.4-0.6); with the elevation of 10.0 SSRS score the risk of depression decreased by 40% (OR = 0.6; 95% CI: 0.5-0.7). Patients with the VFQCS less than 91.3 and SSRSS less than 38.0 had 5.9 times more risk of depression (OR = 5.9; 95% CI: 3.6-9.7). Age (over 60 years) (OR = 0.6; 95% CI: 0.4-0.9) and medical history of cardiovascular disease (OR = 1.7; 95% CI: 1.1-2.5) were independently correlated with depression symptom.

CONCLUSION

The prevalence of depression is high among patients with T2DM in urban district in northeast China. Vision-related quality of life and social support scores are significantly associated with depression. Measures should be taken to screen depressive symptoms in patients with type 2 diabetes patients. These patients need to be intervened with appropriate and effective treatment as early as possible. Meanwhile, behavioral health specialists should guide the patient to get and use social support sources effectively.

[Comparative assessment of the quality of life of keratoconus patients before and after intrastromal keratoplasty]

Surgical treatment of keratectasia, in addition to its cessation, is aimed at increasing the acuity and quality of vision. This can also significantly affect patient's quality of life. The criteria for assessing the quality of life does not always consider the balance between quantitative indicators and subjective perception, which can depend on the psychological aspect of self-esteem.

Purpose - to perform comparative assessment of the quality of life of patients with keratoconus (KK) before and after intrastromal keratoplasty by a newly developed method using an original questionnaire.

MATERIAL AND METHODS

The study included 20 patients (14 men and 6 women, with mean age of 33 years, from 21 to 45 years old; 20 eyes) diagnosed with degree II-IV KK, with non-corrected visual acuity of 0.3 or lower. The original questionnaire with three blocks of questions about subjective assessment of the severity of discomfort associated with the disease, expectations of treatment results and its effectiveness was used to study the quality of life of KK patients who underwent surgery. The evaluation method used a five-point grading scale.

RESULTS

Despite the inability to objectively assess the result of treatment, patients can generally note the trend for improvement. Especially significant are the increase of visual acuity, improvement of general health, feeling of comfort and more optimistic view of one's future. Comparison of the expectations and treatment results has shown that some therapeutic effects are overestimated by the patients, while some others are underestimated. A priori, they overvalue the effects of treatment (actions associated with visual tasks - reading, writing), but at the same time undervalue the characteristics of overall personal and emotional state (except for spatial safety and comfort), i.e. the characteristics that determine the quality of life.

CONCLUSION

The aims of writing a valid and reliable questionnaire have been achieved partially, and its further development requires comparison of the obtained results with psychodiagnostic data, which would reveal the nature of psychological factors that form the quality of life perception in patients with various vision disorders.

Evaluation of the quality of life related to vision after penetrating keratoplasty

INTRODUCTION

Organ and tissue donation and transplantation represent the most important therapeutic advance of current times. The cornea is, by far, one of the most transplanted tissues worldwide due to the immune privilege of this tissue, as well as the advances in microsurgery, existence of cornea banks, preservation of corneas, and use of anti-rejection therapy. However, many patients with successful corneal transplants (with clear corneas) experience poor vision in the post-operative period due to irregular astigmatism, or other complications.

OBJECTIVE

To evaluate the quality of life related to vision in patients undergoing penetrating keratoplasty.

MATERIAL AND METHODS

A cross-analytical study including patients with a history of penetrating keratoplasty, over 18years of age, and at least 6months after surgery. The patients answered the Visual Function Questionnaire25 (VFQ-25) of visual function, a tool validated for use in Spanish, in which the higher the score, the better the quality of life.

RESULTS

Thirty patients (20men and 10women), with a mean age of 61.2±18.7years, were included. The time of evolution after the transplant was 17.7±4months. The total quality of life score was 74.9±21.9, with significance in visual acuity (P<.001), and the presence of systemic comorbidities (P=.018). There was no significance between the transplant reason (P=.098) or ocular comorbidities (P=.119).

CONCLUSION

The results suggest that visual acuity, as well as the presence of systemic comorbidities, has a significant impact on quality of life.

Comparison of postoperative visual performance between bifocal and trifocal intraocular Lens based on randomized controlled trails: a meta-analysis

BACKGROUND

To compare the clinical performance of bifocal and trifocal intraocular lenses (IOLs) in cataract surgery, a meta-analysis on randomized controlled trials was conducted.

METHODS

A comprehensive literature retrieval of PubMed, Science Direct and EMBASE was performed in this systematic review. Clinical outcomes included visual acuity (VA), contrast sensitivity (CS), spectacle independence, postoperative refraction and surgical satisfaction.

RESULTS

There were 8 RCTs included in this study. The difference of uncorrected near VA (UNVA) between the bifocal IOLs and trifocal IOLs had no significance [MD = 0.02, 95%CI: (- 0.03,0.06)]. There was no significant difference in the distant-corrected near VA (DCNVA) with MD of 0.04 [95%CI (- 0.02, 0.10)]. Compared with trifocal group, the uncorrected intermediate visual acuity (UIVA) [MD = 0.09,95%CI:(0.01,0.17)] was significantly worse in the bifocal group. No difference was found in distance-corrected intermediate VA (DCIVA) [MD = 0.09, 95%CI: (- 0.04, 0.23)] between two groups. Analysis on AT LISA subgroup indicated the bifocal group had worse intermediate VA than trifocal group (AT LISA tri 839 M) [MD = 0.18, 95%CI: (0.12, 0.24) for UIVA and MD = 0.19, 95%CI: (0.13, 0.25) for DCIVA]. However, there was no statistically significant difference between the two groups in the uncorrected distance VA (UDVA) and corrected distance visual acuity (CDVA) [MD = 0.01, 95%CI: (- 0.01,0.04) for UDVA; MD = 0.00, 95%CI: (- 0.01,0.01) for CDVA]. The postoperative refraction of bifocal group was similar to that of trifocal group [MD = -0.08, 95% CI: (- 0.19, 0.03) for spherical equivalent; MD = -0.09, 95%CI: (- 0.21, 0.03) for cylinder; MD = -0.09, 95% CI: (- 0.27, 0.08) for sphere]. No difference was found for spectacle independence, posterior capsular opacification (PCO) incidence and patient satisfaction between bifocal IOLs and trifocal IOLs. [RR = 0.89, 95% CI: (0.71, 1.12) for spectacle independence; RR = 1.81, 95% CI: (0.50, 6.54) for PCO incidence; RR = 0.98, 5% CI: (0.86, 1.12) for patient satisfaction].

CONCLUSION

Patients receiving trifocal IOLs, especially AT LISA tri 839 M, have a better intermediate VA than those receiving bifocal IOLs. Near and distance visual performance, spectacle independence, postoperative refraction and surgical satisfaction of bifocal IOLs were similar to those of trifocal IOLs.

Measurement of visual function among patients undergoing corneal transplantation using the VF-14 index in Morocco

OBJECTIVE

To validate the Moroccan version of the VF-14 in candidates for keratoplasty and to assess their quality of life using this tool before and after transplantation.

METHODS

This is a longitudinal prospective study that assessed 57 patients who underwent penetrating keratoplasty, recruited in the ophthalmology service in Marrakech over 5 years. The original VF-14 questionnaire was adapted into Moroccan dialect. The questionnaire was administered before and 2 years after transplantation. The VF-12 questionnaire was also used, deleting the last two items. Data analysis was performed using SPSS 16.0 software. Comparisons of VF-14 scores before and after transplantation used the Wilcoxon test for paired samples.

RESULTS

In total, 57 patients participated in the study. The most frequent indication for surgery was keratoconus (44%). All patients underwent penetrating keratoplasty. Chronbach's alpha value was 0.989 for VF-14 and 0.990 for VF-12. The two scores were negatively correlated with logMAR visual acuity. The strongest correlation was found with VA in the fellow eye. The average best-corrected visual acuity of the eye scheduled for keratoplasty was 1.1±0.16 logMAR. The average of VF-14 was 53±3. After keratoplasty, the average best-corrected visual acuity of operated eye was 0.34±0.31. The average postoperative astigmatism was 3 D. After keratoplasty, an increase in VF-14 score was observed from 53.5 to 81.92 (P<0.001). In postoperative follow-up, graft rejection was noted in two patients and maculopathy in a single patient.

DISCUSSION

Graft transparency, absence of complications, minimal astigmatism, and good visual acuity have long been indicators of a successful corneal transplant. However, this does not provide information on visual quality and its impact on everyday life. It is in this sense that the VF-14 was adapted into several languages, as reliable, valid and sensitive as the original Anglo-American version, to assess objectively and subjectively the quality of life of patients after keratoplasty.

CONCLUSION

With advances in techniques and availability of better materials, surgical success in performing keratoplasty is increasing. At the same time, vision-related quality of life of corneal graft recipients deserves more attention from ophthalmologists.

Development and validation of an Arabic version of the Visual Functioning Index VF-14 for cataract patients

Purpose:

To develop and validate an Arabic version of the Visual Functioning Index (VF-14) for patients with cataracts.

Materials and Methods:

The VF-14 was translated into Arabic by an epidemiologist and an ophthalmologist, both fluent in Arabic and English. The VF-14 was administered to patients diagnosed with cataract at two hospitals in Egypt and two hospitals in Saudi Arabia. Patients were also administered three other forms; the cataract symptoms score (CSS); global measure of vision; and cataract medical form. Internal reliability and external validity were measured. Index sensitivity to visual acuity was detected and potential effective factors were investigated. Correlation analyses were performed. A p value less than 0.05 was considered statistically significant.

Results:

The translated VF-14 was consistent and reliable (σ = 0.763, p < 0.0001). It was also statistically significantly sensitive to vision (p < 0.0001). The mean calculated index was 62.18 ± 19.34, and was highly correlated with; CSS and other scores (p < 0.0001, all cases). Factors that may affect the index are; age, sex, vision, wearing glasses, type, position, and severity of cataract.

Conclusion:

The Arabic VF 14 is a reliable and valid tool for evaluation of both visual functioning and quality of visual life among cataract patients. It is also sensitive to changes in visual acuity, demographic, and clinical characteristics.

Frequency and risk factors of non-retinopathy ocular conditions in people with diabetes: the Singapore Malay Eye Study

AIM

To investigate the frequency and risk factors of non-retinopathy ocular conditions in persons with diabetes.

METHODS

A population-based cross-sectional study of 3176 Malay persons aged between 40 and 79 years in Singapore was conducted. Cataract, glaucoma, refractive errors, age-related macular degeneration, dry eye, epiretinal membrane, ocular hypertension and retinal conditions were assessed based on standardized interviews, clinical examinations and laboratory investigations.

RESULTS

A total of 768 participants (24.2%) had diabetes. People with diabetes were more likely to have cortical cataract (52.1 vs. 37.3%, P < 0.001), ocular hypertension (10.9 vs. 7.4%, P = 0.002) and epiretinal membrane (17.2 vs. 10.1%, P < 0.001) compared with those without diabetes. The odds of having cortical cataract (odds ratio 1.63, 95% CI 1.20-2.20) and epiretinal membrane (among those with previous cataract surgery: odds ratio 1.63, 95% CI 1.20-2.20) were significantly higher in people with diabetes compared with those without. The population attributable risks for cortical cataract and epiretinal membrane because of diabetes were 8.7 and 9.0%, respectively. In persons with diabetes, hypertension and high cholesterol were the major risk factors associated with non-retinopathy eye complications such as ocular hypertension (odds ratio 1.18, 95% CI 1.04-1.33) and retinal emboli (odds ratio 1.99, 95% CI 1.05-3.80).

CONCLUSION

Our results allow clinicians to better inform patients with diabetes that they are more likely to have cortical cataract and epiretinal membranes (those with previous cataract surgery) in addition to diabetic retinopathy. Two modifiable risk factors-blood pressure and cholesterol associated with ocular hypertension and retinal emboli, respectively-are also risk factors for non-retinopathy ocular conditions in persons with diabetes.

Quality of vision after femtosecond laser-assisted descemet stripping endothelial keratoplasty and penetrating keratoplasty: a randomized, multicenter clinical trial

PURPOSE

To compare the quality of vision (straylight and contrast sensitivity) after femtosecond laser-assisted Descemet stripping endothelial keratoplasty (FS DSEK) and penetrating keratoplasty (PK).

DESIGN

Prospective, randomized clinical trial.

METHODS

setting: Multicenter (5 ophthalmic centers in The Netherlands). study population: Eighty eyes of 80 patients with corneal endothelial dysfunction were included and were randomized to FS DSEK or PK. observation procedures: FS DSEK and PK. main outcome measures: Straylight, contrast sensitivity, astigmatism, uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), and visual symptom score.

RESULTS

Straylight at 12 months was 1.37 ± 0.2 logarithm of straylight for FS DSEK and 1.46 ± 0.2 logarithm of straylight for PK (P = .151). During 12 months of follow-up, there was a significant improvement of straylight and contrast sensitivity after FS DSEK (P < .001) and PK (P < .001). The change of straylight and contrast sensitivity correlated significantly with the change of BSCVA after FS DSEK (r = -0.645; r = 0.580) and PK (r = -0.370; r = 0.659). The visual symptom score was comparable between the 2 groups during the 12 months of follow-up.

CONCLUSIONS

Improvement of straylight and contrast sensitivity was significantly correlated with an improvement of BSCVA. Straylight and contrast sensitivity were improved significantly after FS DSEK and were comparable with those after PK, although BSCVA was slightly better in the PK group.

Visual acuity level, ocular morbidity, and the better seeing eye affect sensitivity and responsiveness of the visual function index

PURPOSE

To examine the relation between Visual Function Index-14 (VF-14) scores and VA by accounting for concurrent ocular comorbidities, effect of the better seeing eye (BSE), and VA before and after cataract surgery.

DESIGN

Prospective cohort study.

PARTICIPANTS

A total of 4335 patients with cataract who completed the VF-14 before and after cataract surgery.

METHODS

Collaborating clinicians provided demographic and clinical data before and after cataract surgery. Lowess curves, general linear models, and Spearman correlation coefficients were used to study the relation between the VF-14 and the VA.

MAIN OUTCOME MEASURES

Scores in the VF-14 preintervention, change in VF-14 after surgery, VA before surgery, and VA change after surgery.

RESULTS

General linear models and Spearman correlation coefficients showed a significant (P < 0.0001) association between VF-14 score and VA (measured in decimal fraction) when the preoperative VA was ≤0.5 (20/40) and no association (P > 0.4020) when the VA was >0.5 (20/40). Small VA gains (≤0.5) after surgery only led to significant gains (P < 0.0001) in functionality in patients with other ocular pathologies and whose BSE was the surgical eye. Gains in VA >0.5 had a significant (P < 0.02) effect on VF-14 change scores in most patients.

CONCLUSIONS

The VF-14 seems to be more sensitive when the preoperative VA is <0.5 (20/40), especially in patients whose BSE is the surgical eye. The VF-14 seems responsive to increases in VA if the gains exceed 0.5. For gains <0.5, the VF-14 seems unresponsive, except for patients with other ocular pathologies in whom the BSE before and after surgery is the surgical eye.

Psychological distress and visual functioning in relation to vision-related disability in older individuals with cataracts

OBJECTIVE

To determine whether demographic, health status and psychological functioning measures, in addition to impaired visual acuity, are related to vision-related disability.

METHODS

Participants were 105 individuals (mean age=73.7 years) with cataracts requiring surgery and corrected visual acuity in the better eye of 6/24 to 6/36 were recruited from waiting lists at three public out-patient ophthalmology clinics. Visual disability was measured with the Visual Functioning-14 survey. Visual acuity was assessed using better and worse eye logMAR scores and the Melbourne Edge Test (MET) for edge contrast sensitivity. Data relating to demographic information, depression, anxiety and stress, health care and medication use and numbers of co-morbid conditions were obtained.

RESULTS

Principal component analysis revealed four meaningful factors that accounted for 75% of the variance in visual disability: recreational activities, reading and fine work, activities of daily living and driving behaviour. Multiple regression analyses determined that visual acuity variables were the only significant predictors of overall vision-related functioning and difficulties with reading and fine work. For the remaining visual disability domains, non-visual factors were also significant predictors. Difficulties with recreational activities were predicted by stress, as well as worse eye visual acuity, and difficulties with activities of daily living were associated with self-reported health status, age and depression as well as MET contrast scores. Driving behaviour was associated with sex (with fewer women driving), depression, anxiety and stress scores, and MET contrast scores.

CONCLUSION

Vision-related disability is common in older individuals with cataracts. In addition to visual acuity, demographic, psychological and health status factors influence the severity of vision-related disability, affecting recreational activities, activities of daily living and driving.

Quality of life in glaucoma and three other chronic diseases: a systematic literature review

Chronic diseases have a long-term negative impact on quality of life (QOL). Decreased QOL is associated with increased financial burden on healthcare systems and society. However, few publications have investigated the impact of glaucoma on patients' QOL in comparison with other chronic diseases observed in patients with similar demographic characteristics. To this end, a systematic literature search to assess QOL in glaucoma and three other chronic diseases (osteoporosis, type 2 diabetes mellitus and dementia) was performed. A total of 146 publications were identified that reported QOL using six commonly used generic QOL instruments: 36-, 12- and 20-item Short-Form Health Surveys (SF-36, -12 and -20), EuroQoL (EQ-5D), Sickness Impact Profile (SIP) and the Health Utilities Index-Mark III (HUI-III). The publication breakdown was as follows: glaucoma (10%), osteoporosis (26%), diabetes (52%) and dementia (12%); one publication assessed QOL in glaucoma, diabetes and dementia. QOL was affected to a similar or slightly lesser degree by glaucoma than by osteoporosis, diabetes or dementia. Among the publications reporting SF-36, -12 and -20 evaluations, physical component scores were generally lower than mental component scores across all diseases. QOL was affected more in patients with glaucoma than in demographically matched non-glaucomatous controls according to SF-20 assessment. EQ-5D and SIP results showed that QOL decreased as the severity of glaucoma increased. Patients with glaucoma had the lowest scores on the SIP instrument, indicating better QOL than patients with osteoporosis or diabetes (no data were available on dementia). The HUI-III instrument identified poorer QOL in patients with dementia than other diseases, probably due to cognitive deficits. However, for some of the instruments, data were scarce, and interpretation of the results should be conservative. Although there are limited published QOL studies in glaucoma, its impact on QOL appears to be broadly similar to that of other serious chronic diseases. Development of a QOL instrument that measures vision-specific and general health aspects would better document the impact of glaucoma on QOL and would facilitate comparisons with other chronic disease states.

The impact of cataract surgery on visual functioning, vision-related disability and psychological distress: a randomized controlled trial

PURPOSE

Determine whether there are changes in visual functioning, vision-related disability, health status and mood after cataract surgery.

METHODS

45 adults (mean age = 73.7 years) with bilateral cataract needing surgery for the first eye were recruited from public ophthalmology clinics. The Visual Functioning-14 survey assessed visual disability. Minimal angle of resolution tested visual acuity, and the Melbourne Edge Test examined contrast sensitivity. Demographic, psychological, health and medication use variables were examined. Participants were randomized to either an intervention or control arm. Controls were assessed on two occasions at a 3-month interval before having surgery. The intervention group was assessed 1-2 weeks before surgery and then reassessed 3 months after surgery.

RESULTS

Visual functioning improved for those who had cataract surgery with better visual acuity in the better (P = 0.010) and worse (P = 0.028) eye compared with controls. The intervention group reported fewer difficulties with overall vision-related disability (P = 0.0001), reading (P = 0.004) and instrumental activities of daily living (P = 0.010) post-surgery compared with controls. People with improved depression scores (P = 0.048) after surgery had less difficulty with reading compared with those with unchanged or worsened depression scores. Cataract surgery did not improve health status.

CONCLUSIONS

First eye cataract surgery is effective in improving outcomes in visual functioning and disability. Improved mood after surgery was related to less vision-related disability compared with unchanged or worse depression.

Social and visual function in nystagmus

AIM

To investigate the influence of nystagmus on visual and social function and determine if parents are able to assess visual and social function in children with nystagmus.

METHOD

A postal questionnaire comprising 14 questions related to visual function (VF-14) and questions pertaining to social function were sent to all 1013 members of the Nystagmus Network-a UK based organisation for nystagmus sufferers and their families. Visual and social function scores were compared by regression analysis.

RESULTS

180 adult, 233 parent, and 124 child questionnaires were returned. Idiopathic nystagmus was the most common cause. In adults the mean VF-14 score indicated very low visual function, in the same range as patients assessed in low vision services. Children's visual function scored better than adults, between scores of patients with age related macular disease and corneal grafts. There was a strong correlation between perceived visual and social function for adults (p<0.001) and parental assessment of their children (p<0.001), but not between child self assessment of visual and social function. There was strong correlation between parental and child assessment of visual and social function (p<0.001, p<0.001)

CONCLUSION

Questionnaires indicated that nystagmus is associated with very low visual function. There is a strong correlation between visual and social impairment. The authors have shown for the first time in an ophthalmic disease that parents are able to estimate the impact of nystagmus on their child both in terms of visual and social functioning, although they underestimate the impact of nystagmus on emotional aspects of wellbeing.

Quality of life and visual function in patients with intermediate uveitis

AIMS

To assess visual function, vision related quality of life (VR-QOL), and general health related quality of life (HR-QOL) in intermediate uveitis (IU).

METHODS

VR-QOL and HR-QOL were evaluated in 42 patients with IU using the VCM1 and SF-36 questionnaires, respectively. LogMAR visual acuity (VA), Pelli-Robson contrast sensitivity (CS), Farnsworth-Munsell 100 hue colour vision (CV), and Estermann visual field (VF) were recorded monocularly and binocularly.

RESULTS

Median (interquartile range) visual acuity (VA) and CS of 72 affected eyes were 0.1 (0.015-0.3) and 1.55 (1.35-1.65), respectively. 9.5% of patients had a VCM1 score of more than 2.0, indicating "more than a little" concern over vision. Worse eye VA (p=0.045) and CS (p=0.042) were predictive of a VCM1 score of more than 2.0 independently of age, sex, uveitis duration, laterality and activity, systemic uveitis therapy, and medical co-morbidity. The physical and mental component summary scores of the SF-36 were significantly worse in those who reported significant impairment of vision on the VCM1 than those who did not.

CONCLUSIONS

The majority of patients with IU maintain good visual function and quality of life. VR-QOL impairment in IU correlates with vision in the worse eye and is associated with impaired HR-QOL.

Psychometric properties of vision-related quality of life questionnaires: a systematic review

The increased attention for quality of life (QOL) as an outcome measure has led to the development of numerous questionnaires to assess this construct in the field of ophthalmology. This article presents a systematic review on QOL questionnaires for people with vision impairments. We systematically searched and selected the literature. Furthermore, a rating list with descriptive aspects (e.g. target population) and psychometric aspects (e.g. reproducibility) was developed. The 31 questionnaires that were included in the review were rated on the basis of criteria stated in this rating list. The questionnaires were mostly targeted at cataract patients or visually impaired persons in general. Only a few of the questionnaires demonstrated sufficient psychometric quality. A recent development is the (re-)evaluation of questionnaires with Rasch analysis. This is one of the most important issues to which future research in this field should be directed.

[Measuring patient's quality of life in ophthalmology]

BACKGROUND

The assessment of patient's quality of life is not only of vital importance for clinical trials of new therapies but also becomes more and more implemented into daily clinical therapeutical decisions.

METHODS

Different methods for evaluating quality of life are available. A well-known questionnaire for measuring global quality of life is the Short Form 36 (SF 36). However, in ophthalmology more specific instruments for measuring visual quality of life are needed. We review the usefulness of specific questionnaires such as the Visual Function 14 (VF-14) or the National Eye Institute Visual Function Questionnaire (NEI-VFQ) in their application to common ophthalmologic diseases such as cataract, age-related macular degeneration and glaucoma. Studies applying these methods were identified by a search in the Medline database.

RESULTS

Several instruments to measure visual life quality in ophthalmologic patients are available. Internal consistency and validity are shown.

CONCLUSIONS

Evaluating visual quality of life is an important parameter for assessing ophthalmologic diseases and the value of different therapies. It is an important outcome variable in clinical studies. Furthermore, individual visual quality of life should be considered in individual therapeutic decisions and helps to assess the economic effect of current and new therapies.

Visual Function, Quality of Life and Patient Satisfaction after Ophthalmic Surgery: A Comparative Study

PURPOSE

To compare visual acuity, functional visual performance (VF-14), quality of life (QOL) gain (VF-14 gain) and patient satisfaction in a series of patients undergoing common types of ophthalmic surgery.

METHOD

In a prospective trial, the VF-14 QOL questionnaire was administered to 100 patients who underwent surgery by one surgeon between May 2001 and April 2002. The following surgeries were compared: (1) cataract surgery (non-diabetic patients), (2) cataract surgery (diabetic patients), (3) retinal detachment cryo-buckle procedure, (4) pars plana vitrectomy, (5) silicone oil removal. VF-14 questionnaire responses, visual function and clinical data of all patients were recorded pre-operatively and 1 and 3 months postoperatively.

RESULTS

In comparison to vitreoretinal surgery, patients who underwent cataract surgery achieved higher VF-14 scores and required less time to recover from the procedure (1 month). The QOL gain (VF-14 gain) was significantly higher in patients who had undergone retinal detachment surgery and vitrectomy (p < 0.0001). The lowest QOL gain was registered in diabetic patients after cataract surgery. Patients with pre-existing eye disease, including patients with improved visual acuity, were least satisfied with the final outcome of surgery.

CONCLUSIONS

The highest VF-14 score was achieved by patients with no pre-existing ocular disease, who had undergone cataract surgery. The QOL gain was greater in patients with severer initial ocular conditions. Better patient satisfaction can be achieved in patients with pre-existing eye disease by improving pre-operative patient education.

Assessment of visual function after corneal transplantation: the quality of life and psychometric assessment after corneal transplantation (Q-PACT) study

PURPOSE

Many patients with successful corneal grafts have poor vision postoperatively. This study evaluates changes in vision-related quality of life after penetrating keratoplasty (PK).

DESIGN

Multicenter prospective cohort study.

METHOD

Penetrating keratoplasty candidates from the university-affiliated ophthalmology clinics of four participating centers were enrolled and followed up prospectively. We used the PK-VFQ, a modified version of the Visual Function Index-14, combined with clinical examinations before and at 6 and 12 months after PK. We used multivariate linear regression models to examine predictors of change in PK-VFQ scores.

RESULTS

We studied 74 grafts in 71 eyes of 67 patients aged 23 to 91 (mean, 61) years who were followed up for at least 6 months. Indications for surgery included bullous keratopathy (27%), scarring (16%), keratoconus (16%), dystrophies (16%), and regrafts (15%). Median preoperative visual acuity was 20/200 in the graft candidate and 20/30 in the best eye. Median best-corrected postoperative visual acuity in the operated eyes was 20/60 at 6 months. PK-VFQ scores improved at 6 months in 79% by an average of 13.0 points (range, -16.7 to 67.5). Improvement in PK-VFQ scores was associated with younger age (P =.04), poorer preoperative visual acuity in the best eye (P =.001), and postoperative contact lens use (P =.04) but not with postoperative acuity in the grafted eye (P =.49). Postoperatively, 80% of patients were moderately to very satisfied with their vision, and 97% of patients stated they would have the surgery again.

CONCLUSIONS

Improvement in visual function is inversely associated with visual acuity in the better-seeing eye but does not correlate with the postoperative acuity in the grafted eye. Although most keratoplasties are done unilaterally in the setting of good visual acuity in the contralateral eye, for the majority of patients visual function improves after PK.

Quality of life associated with visual loss: a time tradeoff utility analysis comparison with medical health states

PURPOSE

To assess the visual utility values of patients with ocular disease and to compare these values with those of patients with systemic health states

DESIGN

Cross-sectional utility value assessment.

METHODS

Consecutive patients with ophthalmic diseases were interviewed in a one-on-one fashion using a standardized time tradeoff utility value assessment form. These values were compared with utility values for systemic health states present in the literature.

INTERVENTION

None.

MAIN OUTCOME MEASURE

Time tradeoff utility value on a scale ranging from 1.0 (perfect visual health) to 0.0 (death). The ophthalmic patient groups were stratified into 4 visual groups dependent on the visual acuity in the better-seeing eye. The groups were as follows: group 1, 20/20 to 20/25; group 2, 20/30 to 20/50; group 3, 20/60 to 20/100; group 4, 20/200 to no light perception.

RESULTS

A total of 500 subjects were enrolled in the study. The mean utility values for the visually stratified groups were: group 1, 0.88; group 2, 0.81; group 3, 0.72; group 4, 0.61. Comparable respective systemic health state utility values for each of the ophthalmic groups were: diabetes mellitus, status after kidney transplantation, moderate stroke, and moderately severe stroke.

CONCLUSIONS

Visual loss is associated with a substantial and measurable diminution in quality of life. This diminution in quality of life can be directly compared with that induced by systemic health states.

Visual function index (VF-14) in exudative age-related macular degeneration of long duration

PURPOSE

To evaluate the Visual Function Index (VF-14) questionnaire for its effectiveness in assessing visual function in patients with longstanding exudative age-related macular degeneration (AMD).

DESIGN

Observational case series.

METHODS

The records of 167 consecutive patients with recent neovascularization related to AMD between June 1990 and December 1994 at the Helsinki University Eye Clinic were analyzed in 1999. Of 121 patients still living, 74 (61%) attended the reexamination. After exclusions, data from 62 patients were analyzed. The VF-14 score, plus global assessment scores of satisfaction with vision and quality of vision, in which patients graded the subjective level of difficulty with their vision, best-corrected visual acuity (BCVA), contrast sensitivity, the area of the AMD lesion, and the shortest distance and direction from the center of the fovea to the edge of the subfoveal lesion, were analyzed.

RESULTS

The VF-14 score correlated significantly with BCVA (P <.01), contrast sensitivity (P <.01), and global assessment scores (P <.01), showing stronger correlations with global assessment scores than did BCVA. In multivariate regression analysis, the global assessment scale of overall quality of vision and BCVA in the better eye were significant predictors (P <.001) of the variability in the VF-14 score.

CONCLUSIONS

The VF-14 reflects visual function of patients with late AMD more effectively than BCVA measurement alone. The VF-14 can thus be used to compare the visual handicap of late AMD patients with that of patients with other eye diseases.

Performance and repeatability of the NEI-VFQ-25 in patients with dry eye

PURPOSE

The use of the National Eye Institute Visual Function Questionnaire (NEI-VFQ) has increased as a method of assessing patients' impressions of their vision-specific quality of life. The purpose of this study was to assess the performance and test-retest repeatability of the 25-question format of the NEI-VFQ in patients with dry eye.

METHODS

The self-administered NEI-VFQ-25 was administered to 75 patients with dry eye on two occasions in a university-based optometry practice. Dry eye severity was assessed with use of the European criteria for dry eye. The weighted kappa statistic (kappa(w)) was used to evaluate test-retest repeatability of the NEI-VFQ-25 individual test questions, and the 95% limits of agreement and the intraclass correlation coefficients were calculated for the overall VFQ and subscale scores.

RESULTS

With use of the European dry eye criteria, 21.9% of participants were classified with moderate to severe dry eye. For the sample, the ocular pain subscale score was lower (indicating more ocular pain) than published normative values. Repeatability of individual NEI-VFQ-25 questions ranged from moderate to substantial (kappa(w) values: 0.42 [pain and discomfort] to 0.90 [stay home because of vision]). The intervisit mean (+/- standard deviation) difference in the overall VFQ score was -0.66 +/- 4.26 (95% limits of agreement: -9.02, 7.69), and the intraclass correlation coefficient for the ocular pain subscale was 0.57.

CONCLUSION

Patients with dry eye have lower ocular pain subscale scores. The repeatability of the overall NEI-VFQ score and the subscale scores was moderate to high, and it may be influenced by the number of questions in each subscale.

The VF-14 index of visual function in recipients of a corneal graft: a 2-year follow-up study

PURPOSE

To assess visual functioning and other health-related quality of life outcomes after corneal grafting.

DESIGN

A cohort study of corneal graft recipients observed for a minimum of 2 years after transplantation.

METHODS

Repeated measurements were obtained by telephone interviews preoperatively and later at 1 and 2 years post-corneal transplantation in 217 patients with the following questionnaires: visual function index (VF-14), visual symptom score and global measures of trouble with vision, dissatisfaction with vision, ocular pain, and discomfort. Demographic, past ocular history, repeated best-corrected visual acuity (BCVA), and detailed eye examination data were also collected.

RESULTS

Grafted eyes gained a mean of more than four lines of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart 1 year after transplantation. The mean visual function index (VF-14) score improved from 68% +/- 26% preoperatively to 81% +/- 21% at 1 year. Average visual acuity (VA) and VF-14 values were unchanged at 2 years. The activities of daily living that showed the largest and most significant improvement were reading small print, driving in daytime, and watching television. A number of subjects (9%) presented with a maximum VF-14 score preoperatively, leaving no room for improvement with this outcome index. The VF-14 was especially responsive for corneal graft candidates with low levels of vision before surgery. Blurry vision, pain and discomfort scores, and the global measures of trouble and dissatisfaction with vision also improved after corneal grafting.

CONCLUSION

The VF-14 index of functional visual impairment is a responsive and useful outcome index in recipients of a corneal graft.

Relationship between vision impairment and ability to perform activities of daily living

PURPOSE

To determine the relationship between clinical measures of vision impairment and the ability to perform activities of daily living (ADLs).

METHODS

One hundred and twenty subjects with low vision from a variety of causes participated in the study. Vision impairment was assessed under binocular conditions by measuring distance visual acuity, near word acuity, Melbourne Edge Test contrast sensitivity, Pelli-Robson Chart contrast sensitivity and visual fields. The ADL performance was assessed using the Melbourne Low Vision ADL Index (MLVAI), which is in part an observed performance assessment of instrumental ADLs and in part a self-report assessment of basic self-care ADLs.

RESULTS

All vision measures had a high, statistically significant correlation with MLVAI total score. Near word acuity, had the strongest correlation (r(s) = -0.86, p < 0.001), followed by Melbourne Edge Test contrast sensitivity (r(s) = 0.80, p < 0.001). Visual field had the weakest correlation (r(s) = 0.56, p < 0.001). Together, age, near word acuity, Melbourne Edge Test contrast sensitivity and visual field accounted for 82.2% (adjusted R2, p < 0.001) of the variance in MLVAI total score. All correlations obtained were higher for the observed performance assessment of instrumental ADLs than for the self-report assessment of basic self-care ADLs.

CONCLUSIONS

Clinical vision impairment measures are highly correlated with capacity to perform ADLs, as measured by the MLVAI.

Vision-specific instruments for the assessment of health-related quality of life and visual functioning: a literature review

Clinically objective measures such as visual acuity or visual field provide an assessment of a patient's visual status. However such measures may not reflect the degree of visual impairment the patient experiences in his or her daily activities. Visual impairment has been shown to have negative effects on health-related quality of life (HR-QOL) and a significant impact on daily functioning, including social activities. As such, there is a growing recognition of the importance of patient-reported outcomes of visual functioning. This review examines the development and psychometric properties of 22 vision-specific instruments assessing visual functioning and/or the impact of visual impairment on HR-QOL or daily activities. Issues relevant to assessing vision-specific subjective outcomes are reviewed, with specific application of the reviewed instruments. Three instruments, the Activities of Daily Vision Scale, National Eye Institute Visual Function Questionnaire, and Visual Function Index have been well validated and widely used, but others also show promise. To fully capture the benefits of a new ophthalmology treatment (or new treatment for eye disease) a valid and reliable visual instrument, in which the psychometric performance has been demonstrated in the particular ocular condition being treated, should be utilised.

Preliminary investigation of the responsiveness of the Melbourne Low Vision ADL index to low-vision rehabilitation

PURPOSE

To conduct a preliminary investigation on the ability of the Melbourne Low Vision ADL Index to detect changes in functional ability as a result of low-vision rehabilitation.

METHODS

Twenty two subjects with age-related macular degeneration (ARMD) who were newly referred to the Kooyong Low Vision Clinic were recruited. The Melbourne Low Vision ADL Index was administered prerehabilitation and postrehabilitation. Changes in scores and effect size statistics were analyzed.

RESULTS

The median total score for the subjects prerehabilitation was 67, and the median total score postrehabilitation was 76. The difference in prerehabilitation and postrehabilitation scores was statistically significant (Wilcoxon signed rank test = 248.5, p < 0.001). The mean change score for the total Melbourne Low Vision ADL Index was 9.3 (SD, 5.6). Thus the overall effect size statistic (mean change score divided by SD of prerehabilitation score) was 0.78.

CONCLUSIONS

This preliminary investigation indicates that the Melbourne Low Vision ADL Index is responsive to a rehabilitation program for patients with ARMD. It has potential to be used as a measure of low-vision rehabilitation outcomes.

Contrast and glare testing in the assessment of visual performance of candidate eyes for penetrating keratoplasty

PURPOSE

To determine whether visual acuity (VA) measurements performed at low levels of contrast and glare are a better diagnostic tool for determining whether corneal clouding warrants surgery.

METHODS

Fifty-nine subjects were recruited from among the candidates for corneal graft. Monocular VA was measured with three Regan contrast VA charts: 96, 25, and 11%, with and without glare provided by the Brightness Acuity Tester (BAT). The discriminative ability of the tests was estimated using the area (AR) under receiver operating characteristic (ROC) curves. Associations between the different VA tests and the Visual Function Index (VF-14) score were studied, using Spearman coefficients.

RESULTS

When comparing candidate eyes with contralateral eyes with corneal disease, lower contrasts VA tests provided greater discriminative power. VA measurements made with glare also tended to provide greater discrimination. In fact, discrimination was best with 11% contrast VA with glare, but "testability" was poor. The most practical test in a clinical setting, which retained high discriminative ability (0.798), was the 25% contrast VA with glare. The eye with the best VA correlated strongly with the VF-14, especially at 25% contrast without glare, resulting in an Rs of -0.729.

CONCLUSION

Twenty-five percent contrast VA with BAT could help the practitioner to decide whether a corneal transplant is warranted when symptoms of reduced vision are more important than what high-contrast VA might indicate.