Self-assessment of the quality of vision: association of questionnaire score with objective clinical tests

Vision-Related Quality of Life in Patients With Rhegmatogenous Retinal Detachment Treated With Pars-Plana Vitrectomy: Impact of Gas Tamponade

PURPOSE

To investigate changes in vision-related quality of life in patients treated with pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) and compare groups according to the type of gas tamponade used.

METHODS

Participants in this study were 48 patients with RRD who were treated with PPV and gas tamponade (sulfur hexafluoride (SF₆) or perfluoropropane (C₃F₈)) without internal limiting membrane peeling. All participants underwent slit-lamp examination, fundoscopy, axial-length measurement, and completed the Vision Function Questionnaire-25 (VFQ-25) at month six postoperatively. We compared VFQ-25 composite and subscale scores in the SF₆ and C₃F₈ groups and investigated any correlations between age, best corrected visual acuity (BCVA), axial length, and VFQ-25 scores.

RESULTS

The demographic and clinical characteristics of the two groups (axial length, macular status, retinal detachment extent, duration of symptoms, and lens status) were comparable between the two groups. We found a statistically significant decrease in general vision (GV), ocular pain (OP), and driving (D) scores in the C₃F₈ group compared to the SF₆ group. The VFQ-25 composite score was comparable in the two groups. Similarly, all other subscales of the VFQ-25 did not differ significantly between the two groups. Age and BCVA did not significantly correlate with VFQ-25 composite and subscale scores.

CONCLUSION

Specific VFQ-25 subscales were decreased in patients with RRD treated with C₃F₈ as a gas tamponade compared to SF₆. This finding warrants further research in the tamponade agents used in PPV surgeries.

Should clinical automated perimetry be considered for routine functional assessment of early/intermediate age-related macular degeneration (AMD)? A systematic review of current literature

Purpose

There is growing interest in functional testing for early/intermediate age‐related macular degeneration (iAMD). However, systematic evaluation of existing clinical functional tests is lacking. This systematic review examines evidence for using clinical automated perimetry in routine assessment of early/iAMD.

Recent findings

PubMed, Web of Science Core Collection, and Embase were searched from inception to October 2020 to answer, is there evidence of visual field defects in early/iAMD, and if so, are early/iAMD visual field defects linked to real‐world patient outcomes? Articles using clinical automated perimetry (commercially accessible and non‐modified devices/protocols) were included. Microperimetry was excluded as this has yet to be incorporated into clinical guidelines. The primary outcome was global visual field indices including mean deviation (MD), pattern standard deviation (PSD), mean sensitivity (MS) and frequency of defects. The secondary outcome was any real‐world patient outcome including quality of life and/or activities of daily living indices. Twenty‐six studies were eligible for inclusion and all studies were observational. There was consistent evidence of worsened MD, PSD, MS and frequency of defects for early/iAMD compared to normal eyes under photopic, low‐photopic and scotopic conditions. Meta‐analysis of studies using standard automated perimetry (SAP) under photopic conditions revealed worsened MD (−1.52dB [−2.27, −0.78 dB]) and MS (−1.47dB [−2, −0.94 dB]) in early/iAMD compared to normal eyes, representing large statistical effect sizes but non‐clinically meaningful reductions. There was insufficient data for meta‐analyses regarding other clinical automated perimetry protocols. Only one study assessed a real‐world patient outcome (on‐road driving performance), with no significant link to visual field outcomes in early/iAMD.

Summary

Significant reduction of global visual field indices is present in early/iAMD, but not clinically meaningful using SAP under photopic conditions. Translational relevance of visual field outcomes to patient outcomes in early/iAMD remains unclear. Thus, SAP under photopic conditions is unlikely to be useful for routine assessment of early/iAMD.

Implementation of PROMIS® in an Optometry Clinic

PURPOSE

The full utility of general health Patient-Reported Outcomes Measurement Information System® (PROMIS) surveys in the eye care setting has not been previously demonstrated. This report demonstrates the feasibility of implementing PROMIS in an eye care clinic.

PATIENTS AND METHODS

Over 2 months, general health and functioning PROMIS surveys were offered to all patients in an optometric clinic in Rochester, NY. Demographic and clinical variables were recorded along with percent completion and time to completion of the survey.

RESULTS

Across 651 patients, 258 chose to attempt PROMIS. Patients with low visual acuity were less likely to attempt the survey (p=0.049), and younger patients were more likely to complete the survey (p=0.025); no other patient characteristics were found to differ between those who did and did not participate in, nor complete, PROMIS. A total of 193 patients completed the survey (74.8%) in a mean time of 6.36 minutes (range = [1.43, 51.92] minutes; standard deviation = 5.62 minutes). Time to completion did not vary significantly across any groups.

CONCLUSION

Our relatively high completion rate among those who attempted PROMIS indicates that PROMIS surveys are feasible to implement in an optometry clinic. While most patients completed the survey in little time, the large range of time to completion may indicate that some patients had difficulty completing the survey. Furthermore, the significant difference in visual acuity between those who participated in the survey and those who did not highlights the need to address the way PROMIS is delivered in order to foster greater inclusion.

Self-report Measures of Hearing and Vision in Older Adults Participating in the Canadian Longitudinal Study of Aging are Explained by Behavioral Sensory Measures, Demographic, and Social Factors

OBJECTIVES

Our objectives were to (1) determine the prevalence of self-reported hearing, vision, and dual sensory (both vision and hearing) difficulties in older Canadian adults; (2) examine the association between self-report and behavioral sensory measures; and (3) controlling for behavioral sensory measures, examine variables that might explain the self-reported sensory difficulty, including age, sex, cultural background, socioeconomic status, nonsensory comorbidities, cognitive function, and social factors.

DESIGN

We used baseline data collected from the 30,097 participants of the comprehensive cohort of the Canadian Longitudinal Study on Aging. Participants who were 45 to 85 years of age (mean age = 63 years, SD = ± 10.25) were recruited using provincial health registries and random-digit dialing. Analyses were conducted for the sample as a whole or stratified by age. Behavioral sensory data for hearing (pure-tone audiometry) and vision (pinhole-corrected visual acuity) were collected at 11 data collection sites. Self-reported sensory and personal data were obtained through in-person interviews. "Difficulty" was defined as a response of "fair" or "poor" (versus "excellent," "very good" or "good") to questions about hearing ability (using a hearing aid if used) and vision (using glasses or corrective lenses if used). Individuals with both hearing and vision difficulties were defined as having dual sensory difficulties. Variables associated with self-reported sensory difficulties were analyzed with multiple regression models.

RESULTS

Objective 1. The prevalence of impairments based on behavioral measures was higher than the prevalence of difficulties based on self-report measures. The prevalence based on both types of measures increased with age, but the increase was steeper for behavioral measures. Objective 2. In addition to the expected positive associations between self-report and behavioral measures of hearing [odds ratio (OR) = 2.299)] and vision (OR = 15.247), self-reported sensory difficulty was also explained by other within-modality sensory variables, such as the symmetry of impairment and the use of aids. Objective 3. Controlling for behavioral measures of hearing (better-ear pure-tone average) or vision (better-eye visual acuity), older participants were significantly less likely than younger participants to self-report sensory difficulty. Sensory difficulties were reported more often by males and by those with more comorbid health conditions. Compared to those who did not report vision difficulties, those who did report them were more likely to also report hearing difficulties (OR = 2.921) and vice versa (OR = 2.720). There were modality-specific associations with variables relevant to social participation; for example, independent life space was associated with hearing difficulties, and perceived availability of social support and loneliness with vision difficulties.

CONCLUSIONS

The low prevalence of self-reported sensory difficulties relative to the behavioral measures of sensory impairments indicates that (a) a simple screening question about sensory ability may not be sufficient to identify older adults who are in the early stages of sensory decline, and (b) self-reported sensory ability is associated with sensory and nonsensory factors. Age, gender, and comorbidities are the most notable nonsensory predictors for both self-reported hearing and vision. These findings shed light on how the self-reported sensory difficulties of older adults may reflect clinical measures of sensory impairment as well as nonsensory factors.

A Scoping Review of Quality of Life Questionnaires in Glaucoma Patients

PRECIS

Multiple questionnaires exist to measure glaucoma's impact on quality of life (QoL). Selecting the right questionnaire for the research question is essential, as is patients' acceptability of the questionnaire to enable collection of relevant patient-reported outcomes.

PURPOSE

QoL relating to a disease and its treatment is an important dimension to capture. This scoping review sought to identify the questionnaires most appropriate for capturing the impact of glaucoma on QoL.

METHODS

A literature search of QoL questionnaires used in glaucoma, including patient-reported outcomes measures, was conducted and the identified questionnaires were analyzed using a developed quality criteria assessment.

RESULTS

Forty-one QoL questionnaires were found which were analyzed with the detailed quality criteria assessment leading to a summary score. This identified the top 10 scoring QoL questionnaires rated by a synthesis of the quality criteria grid, considering aspects such as reliability and reproducibility, and the authors' expert clinical opinion. The results were ratified in consultation with an international panel of ophthalmologists (N=49) from the Educational Club of Ocular Surface and Glaucoma representing 23 countries.

CONCLUSIONS

Wide variability among questionnaires used to determine vision related QoL in glaucoma and in the responses elicited was identified. In conclusion, no single existing QoL questionnaire design is suitable for all purposes in glaucoma research, rather we have identified the top 10 from which the questionnaire most appropriate to the study objective may be selected. Development of a new questionnaire that could better distinguish between treatments in terms of vision and treatment-related QoL would be useful that includes the patient perspective of treatment effects as well as meeting requirements of regulatory and health authorities. Future work could involve development of a formal weighting system with which to comprehensively assess the quality of QoL questionnaires used in glaucoma.

Questionnaires for assessing self-perceived physical fitness: A systematic review

This systematic review aimed to identify and summarize the reliability and validity of the questionnaires that have been designed for assessing self-perceived physical fitness (PF) in elderly people. Three electronic databases (MEDLINE/PubMed, SPORTDiscuss and Scopus) were searched systematically from their inception until March 2021 in order to find investigations that provided information on the reliability and/or validity of questionnaires used for identifying self-perceived PF in this population. Nine studies fulfilled these criteria, and seven questionnaires were found, five of them being specifically designed for the elderly. Concurrent validity was mostly obtained by correlating the items of the questionnaires with PF field-based tests, and poor to moderately strong associations were obtained. Test-retest reliability was informed in five questionnaires, and high values were generally observed. The SRFit questionnaire showed the best rates of concurrent validity and test-retest reliability, although these results were partially affected by the mean age of the sample. The lack of a rigorous methodological approach when designing these questionnaires detected in this review, asks for further studies using quantitative and qualitative approaches in order to create more solid and valid measurement tools.

Patient Reported Outcomes in Microbial Keratitis

PURPOSE

The aim of this investigation was to study the patient-reported outcomes of patients with microbial keratitis (MK) using the 9-item National Eye Institute-Visual Function Questionnaire (NEI VFQ-9).

METHODS

Using the Sight Outcomes Research Collaborative ophthalmology electronic health record repository, patients with MK and control patients who completed the NEI VFQ-9 within 7 days of their appointment were identified. The questionnaire is scored as a mean of the 9 items on a scale from 0 to 100, with higher scores indicating better functioning. Composite and individual item scores were compared between groups using the analysis of variance.

RESULTS

In total, 916 questionnaires were completed from patients with acute MK (n = 84), nonacute MK (n = 30), MK with a corneal transplant (n = 21), from controls seen in a satellite comprehensive ophthalmology clinic (n = 528), and controls seen at a subspecialty ophthalmology clinic (n = 253). The mean NEI VFQ-9 composite scores per group were 66.6 (SD = 26.8), 78.1 (SD = 17.1), 58.6 (SD =21.6), 88.0 (SD = 10.2), and 83.5 (SD = 13.0), respectively (P < 0.0001). Both patients with acute MK and patients with MK requiring transplant reported significantly worse function than nonacute MK, comprehensive, and specialty patients. Patients with nonacute MK reported significantly worse function than comprehensive control patients (all Tukey-adjusted P < 0.05).

DISCUSSION

Patients who had or eventually require corneal transplant for management of their MK report worse visual function than patients with nonacute MK. This may be important in helping physicians counsel their patients.

Functional Aging Index Complements Frailty in Prediction of Entry Into Care and Mortality

BACKGROUND

The aim of this study was to develop a functional aging index (FAI) that taps four body systems: sensory (vision and hearing), pulmonary, strength (grip strength), and movement (gait speed) and to test the predictive value of FAI for entry into care and mortality.

METHOD

Growth curve models and Cox regression models were applied to data from 1,695 individuals from three Swedish longitudinal studies of aging. Participants were aged 45-93 at intake and data from up to eight follow-up waves were available.

RESULTS

The rate of change in FAI was twice as fast after age 75 as before, women demonstrated higher mean FAI, but no sex differences in rates of change with chronological age were identified. FAI predicted entry into care and mortality, even when chronological age and a frailty index were included in the models. Hazard ratios indicated that FAI was a more important predictor of entry into care for men than women, whereas it was a stronger predictor of mortality for men than women.

CONCLUSIONS

Measures of biological aging and functional aging differ in their predictive value for entry into care and mortality for men and women, suggesting that both are necessary for a complete picture of the aging process across genders.

Development of the neurotrophic keratopathy questionnaire: qualitative research

BACKGROUND

Neurotrophic keratopathy/keratitis (NK) is a rare disease of the cornea that can lead to anatomical loss of the eye. Little is known about the NK experience from the patients' perspective. The objectives of this study were to examine the symptomatic experience and impacts of NK on patients and assess the overall comprehension, relevance, and content validity of a new questionnaire.

METHODS

This was a cross-sectional, qualitative study conducted with NK patients with varying levels of disease severity, recruited from one clinical site. One-on-one interviews using concept elicitation and cognitive interviewing techniques were conducted.

RESULTS

Fourteen NK patients participated; 64.3% were female (n = 9), mean age was 65.7 ± 13.3, and 14.3% (n = 2), 21.4% (n = 3), and 64.3% (n = 9) were classified as Mackie stage I, stage II, or stage III, respectively. Participants reported 24 concepts, including: redness (n = 12, 86%), sensitivity to light (n = 11, 79%), general discomfort (n = 9, 64%), dry eye (n = 9, 64%), reduced visual acuity (n = 9, 64%), blurred vision (n = 8, 57%), and eye fatigue (n = 8, 57%). No new concepts were reported after the 13th interview. The most frequently reported impacts included frustration (n = 10, 71%), driving impairment (n = 8, 57%), reading impairment (n = 7, 50%), difficulty watching television (n = 7, 50%), and concern with potentially losing their eyesight due to NK (n = 6, 43%). Participants provided positive feedback on the draft NK Questionnaire (NKQ) and felt that it was comprehensive and relevant to their experience with NK. Additionally, the recall period, instructions, item concepts, and response options were well-understood by participants. Minor revisions were made to the tool for consistency (i.e., the timeframe "in the past 7 days" was added to items 12-14); item 14 was modified to include "how often"; examples were added to item 9.

CONCLUSIONS

The results of the concept elicitation portion of the qualitative study support the content validity of the draft NKQ. The clinically significant concepts identified in the literature and raised during concept elicitation are included as items in the questionnaire. Further assessment of the psychometric properties should be conducted in support of this new tool to measure the effect of new treatments on symptoms and impacts associated with NK.

How do different lighting conditions affect the vision and quality of life of people with glaucoma? A systematic review

This article is a systematic review of evidence regarding the impact of different lighting conditions on the vision and quality of life (QoL) of people with primary open-angle glaucoma (POAG). A systematic literature search was carried out using CINAHL, MEDLINE, PsycARTICLES, PsycINFO, Embase, and Ovid Nursing Database for studies: published up to April 2019; including people diagnosed with POAG; and assessing visual function or QoL in response to changing lighting/luminance levels or glare. Two researchers independently screened studies for eligibility. Data were extracted from eligible studies regarding study design, participant characteristics, outcomes, and results. Quality of included studies was critically appraised. Of 8437 studies, 56 eligible studies were included. Studies investigated the effects of lighting on the following domains among people with POAG: QoL (18/56), psychophysical measures (16/56), functional vision (10/56), activities of daily living (10/56), and qualitative findings (2/56). POAG negatively affects low-luminance contrast sensitivity, glare symptoms, and dark adaptation time and extent. In vision-related QoL questionnaires, people with POAG report problems with lighting, glare, and dark adaptation more frequently than any other domain. These problems worsen with progressing visual field loss. Early-stage POAG patients experience significantly more difficulties in low-luminance or changing lighting conditions than age-matched controls (AMCs), challenging perceptions of early-stage POAG as asymptomatic. However, performance-based studies seldom show significant differences between POAG participants and AMCs on tasks simulating daily activities under non-optimal lighting conditions. Further research with larger samples is required to optimise ambient and task-oriented lighting that can support patients' adaptation to POAG.

Development of a vision impairment score for the assessment of functional vision in dogs: Initial evidence of validity, reliability, and responsiveness

AIM

To describe the development and initial validation of a questionnaire measuring functional vision in dogs.

METHODS

A 17-item survey was designed to quantify functional vision in dogs. The Vision Impairment Score (VIS) was determined by summing responses to each question. Questions were assigned to one of five subcategories: overall vision, daily activities, peripheral vision, near vision, and distance vision. Content validity was established during development phases, and construct validity via comparing results of known groups (blind vs sighted; normal vs impaired vision; surgery to improve vision vs nonrestorative surgery), and through factor analysis. Concurrent criterion validity was determined with use of a validated health-related quality-of-life (HRQL) assessment tool. Reliability and responsiveness assessments were investigated using intraclass correlation coefficient (ICC) and effect size (ES), respectively.

RESULTS

Responses (221) from 201 dog owners were included. Compared to sighted dogs (n = 153), blind dogs (n = 48) had a higher VIS and greater impairment in all subcategories. Among sighted dogs, a higher VIS was obtained in dogs with low vision compared to those with normal vision (P < 0.001). A higher VIS was associated with poorer HRQL (P < 0.001). Perfect reliability was obtained for 6/17 questions, and excellent reliability for 11/17 questions (intraclass correlation 1.0 and >0.9, respectively), and the VIS was highly responsive to therapeutic intervention (effect size 1.46).

CONCLUSION

Results suggest the VIS may be clinically useful in assessing and obtaining a quantifiable measure of functional vision in dogs. Ongoing validation of the tool for clinical use is needed.

A forced-choice preferential looking task for the assessment of vision in dogs: pilot study

OBJECTIVES

To describe preliminary use of a forced-choice preferential looking task for the clinical assessment of vision in dogs.

MATERIALS AND METHODS

The vision of 18 pet dogs was investigated in two separate studies using a forced-choice preferential looking task: multiple observers watched eye, head and body movements on video recordings to identify cues suggesting when a dog had seen the feature of interest. Human observer reliability was determined using eight dogs and computer-generated stimuli. Visual acuity was assessed using computer-generated grating stimuli: in real-time, an observer watched each dog's eye movement patterns and behaviour to decide whether each grating was seen. Stimuli were presented in a step-wise manner and were controlled by the observer. Acuity was estimated as the highest spatial frequency the dog was determined to have seen.

RESULTS

Median estimated visual acuity was better at 1 m compared to that at 3 m. Average test time was longer at a 3-m distance than at 1 m. Inter- and intra-observer reliability was better from 1 m than from 3 m.

CLINICAL SIGNIFICANCE

Preliminary use of a forced-choice preferential looking task for measurement of visual acuity in dogs has potential use as a clinical tool for the assessment of vision in dogs.

Glaucoma Patient-Reported Concerns and Associated Factors

PURPOSE

To assess the character and degree of concerns of glaucoma patients and identify demographic/clinical factors affecting the concerns.

DESIGN

Prospective cross-sectional study.

METHODS

A questionnaire that addressed patients' concerns was administered to consecutive glaucoma patients. Severity of concern was scored with a scale of 0-5 in order of increasing severity. Age, sex, intraocular pressure, visual field (VF) mean deviation (MD), number of antiglaucoma medications, history of glaucoma surgery, and employment status were recorded.

RESULTS

Questionnaire results of 152 patients (mean VF MD, -8.03 ± 7.86 dB [better eye] and -16.06 ± 10.22 dB [worse eye]; mean age, 69 ± 14 years) were analyzed. Severity of concern was greatest for general eyesight (2.92/5.00) and visual symptoms (2.78/5.00), followed by activities (2.20/5.00) and socioeconomic factors (2.13/5.00), and then ocular symptoms (1.69/5.00) (P < .001). The most common concerns within each domain were blurry vision (32%), reading small print (34%), medical costs (26%), and dryness (32%). Concern about visual symptoms correlated with VF MD of the better eye (r = -0.258; P = .001) and worse eye (r = -0.233; P = .004). Concern about activities correlated with history of glaucoma surgery (r = 0.148; P = .023) and VF MD of the better eye (r = -0.284; P < .001) and worse eye (r = -0.295; P < .001). Concern about socioeconomic factors correlated with VF MD of the better eye (r = -0.245; P = .003) and age (r = -0.260; P = .001).

CONCLUSIONS

Glaucoma patients reported varied degrees of concern regarding items associated with quality of life. Certain items may be more concerning than others. Severity of some concerns increased with more severe VF loss, prior glaucoma surgery, or younger age.

Developing an Item Bank to Measure Quality of Life in Individuals With Glaucoma, and the Results of the Interview With Patients: The Effect of Visual Function, Visual Field Progression Rate, Medical, and Surgical Treatments on Quality of Life

PURPOSE

To construct a new item bank to measure quality of life (QOL) in glaucoma patients and to evaluate glaucoma patients' QOL using the item bank.

METHODS

An item bank of questions was generated through a literature review of QOL instruments useful for glaucoma patients. Using this item bank, a cognitive survey was performed on 203 patients with glaucoma (112 males and 91 females, 61.9±11.9 y old; mean±SD). The results were then analyzed using the Rasch analysis, and the Rasch-derived disability scores were predicted using linear modelling and the following clinical parameters: age, mean total deviation (mTD) in superior and inferior visual field (mTDsup/mTDinf), mTD progression rate, better visual acuity, worse visual acuity, number of eye drops administered per day, number of trabeculectomy procedures experienced in both eyes.

RESULTS

A total of 23 questionnaires of QOL in glaucoma patients were identified resulting in an item bank of 187 questions related to the following tasks: reading/writing, walking, going out, eating and driving (direct disability) as well as questions concerned with worry/anxiety, social participation, and physical symptoms (indirect disability). In the optimal model for direct disability, age and mTDinf were identified as significant predictors, whereas number of eye drops administered per day and number of trabeculectomy experienced were included in the optimal model for indirect disability.

CONCLUSIONS

A new item bank to measure QOL in glaucoma patients was developed and evaluated. Age and mTDinf were found to be related to direct disability while medical and surgical treatments were related to indirect disability.

Development and validation of a vision and night driving questionnaire

PURPOSE

Night-time driving difficulties are a common concern of older drivers and those with eye disease. This study aimed to develop and validate a questionnaire for assessing vision-related night driving difficulties in older drivers.

METHODS

Items from existing vision-related quality of life questionnaires and driving studies were used to develop a questionnaire that was completed by 283 participants who reported visual difficulties for night driving (65% female, 50 to >80 years). The questionnaire included items relating to demographic and night driving characteristics (seven items), general vision ratings (eight items), vision-related night driving difficulties (11 items), and a single open question about specific night driving difficulties. The vision-related night driving difficulty items were analysed separately using Rasch analysis to form the vision and night driving questionnaire (VND-Q). Rasch analysis assessed validity and psychometric properties of the scale. Generalised linear regression models examined associations between VND-Q scores and age, gender, amount of night driving, self-rated vision, and eye conditions. Test-retest repeatability was assessed using intra-class correlation analysis and Bland-Altman methods of agreement for a subset of 30 participants.

RESULTS

Rasch analysis indicated that a nine-item VND-Q scale was unidimensional, valid and reliable, and showed excellent discriminant ability (person separation index 3.04; person reliability 0.90). Targeting was better for those with greater self-reported night driving difficulties. Participants with self-reported bilateral eye conditions and worse self-reported general vision ratings had significantly more night driving difficulties with the VND-Q scale than individuals without eye conditions (p = 0.03) and with better general vision ratings (p < 0.001). Females reported more difficulties than males (p < 0.001) and drove shorter distances at night per week which was also associated with greater difficulties (p < 0.001). A repeatability coefficient (Rc ) of 2.07 demonstrated excellent test-retest repeatability.

CONCLUSIONS

The nine-item VND-Q is a unidimensional and reliable questionnaire allowing quantification of the level of visual difficulties that older drivers report at night. The development of this questionnaire is an important step in providing a reliable and validated instrument for use to guide appropriate investigations, referrals, or interventions in clinical and research settings.

Patient-reported outcomes in randomised controlled trials on age-related macular degeneration

BACKGROUND/AIMS

The purpose of this systematic review was to identify the frequency and type of patient-reported outcome measures (PROMs) used in recent randomised controlled trials (RCTs) for age-related macular degeneration (AMD).

METHODS

The authors conducted a systematic search between January 2010 and November 2013 in MEDLINE, EMBASE, Scopus, Cochrane Library (Central) and the clinical trials registries (http://www.controlled-trials.com and http://www.ClinicalTrials.gov) according to defined inclusion criteria (RCTs on AMD in English). Two independent reviewers evaluated studies for inclusion. One reviewer extracted data of included studies, and a second masked reviewer assessed 10% to confirm accuracy in data collection. Reference lists of included papers and appendices of relevant Cochrane systematic reviews were scanned to identify other relevant RCTs. Information collected on extracted outcomes was analysed using descriptive statistics.

RESULTS

Literature and registry search yielded 3816 abstracts of journal articles and 493 records from trial registries. A total of 177 RCTs were deemed to have met inclusion criteria. Of the 858 outcomes reported, 38 outcomes were identified as PROMs (4.4%). Of the 177 RCTs examined, PROMs were used in 25 trials (14.1%). The National Eye Institute Visual Function Questionnaire-25 was the most frequently used PROM instrument (64% of RCTs with PROMs included).

CONCLUSIONS

This review highlights that a small proportion of AMD RCTs included PROMs as outcome measures and that there was a variety in the instruments used.

TRIAL REGISTRATION NUMBER

The systematic review was registered in the PROSPERO database for systematic reviews, registration number CRD42014010040.

Quality assessment of ophthalmic questionnaires: review and recommendations

PURPOSE

The aim of this article was to systematically review all the available ophthalmic patient-reported outcome (PRO) instruments (questionnaires) that demonstrated interval measurement properties to identify the instruments with the highest psychometric quality for use in different eye diseases and conditions.

METHODS

An extensive literature review was carried out to identify all existing ophthalmic PRO instruments. Instruments were then excluded if they did not have demonstrable interval measurement properties; the remaining instruments were reviewed. The quality of the following psychometric properties was assessed: content development (initial item development process), performance of the response scale, dimensionality (whether the instrument measures a single construct), measurement precision, validity (convergent, concurrent, discriminant, and known groups), reliability (test-retest), targeting (whether the items are appropriate [e.g., difficulty level] for the population), differential item functioning (whether subgroups of people respond differently to an item), and responsiveness.

RESULTS

The search identified 48 PRO instruments that demonstrated interval measurement properties, and these were relevant to nine applications: glaucoma, dry eye, refractive errors, cataract, amblyopia and strabismus, macular diseases, adult low vision, children low vision, and others. These instruments were evaluated against the psychometric property quality criteria and were rated for quality based on the number of criteria met.

CONCLUSIONS

This review provides a descriptive catalog of ophthalmic PRO instruments to inform researchers and clinicians on the choice of the highest-quality PRO instrument suitable for their purpose.

An enhanced functional ability questionnaire (faVIQ) to measure the impact of rehabilitation services on the visually impaired

AIM

To develop a short, enhanced functional ability Quality of Vision (faVIQ) instrument based on previous questionnaires employing comprehensive modern statistical techniques to ensure the use of an appropriate response scale, items and scoring of the visual related difficulties experienced by patients with visual impairment.

METHODS

Items in current quality-of-life questionnaires for the visually impaired were refined by a multi-professional group and visually impaired focus groups. The resulting 76 items were completed by 293 visually impaired patients with stable vision on two occasions separated by a month. The faVIQ scores of 75 patients with no ocular pathology were compared to 75 age and gender matched patients with visual impairment.

RESULTS

Rasch analysis reduced the faVIQ items to 27. Correlation to standard visual metrics was moderate (r=0.32-0.46) and to the NEI-VFQ was 0.48. The faVIQ was able to clearly discriminate between age and gender matched populations with no ocular pathology and visual impairment with an index of 0.983 and 95% sensitivity and 95% specificity using a cut off of 29.

CONCLUSION

The faVIQ allows sensitive assessment of quality-of-life in the visually impaired and should support studies which evaluate the effectiveness of low vision rehabilitation services.

Development of a vision-targeted health-related quality of life item measure

PURPOSE

To develop a vision-targeted health-related quality of life (HRQOL) measure for the NIH Toolbox for the Assessment of Neurological and Behavioral Function.

METHODS

We conducted a review of existing vision-targeted HRQOL surveys and identified color vision, low luminance vision, distance vision, general vision, near vision, ocular symptoms, psychosocial well-being, and role performance domains. Items in existing survey instruments were sorted into these domains. We selected non-redundant items and revised them to improve clarity and to limit the number of different response options. We conducted 10 cognitive interviews to evaluate the items. Finally, we revised the items and administered them to 819 individuals to calibrate the items and estimate the measure's reliability and validity.

RESULTS

The field test provided support for the 53-item vision-targeted HRQOL measure encompassing 6 domains: color vision, distance vision, near vision, ocular symptoms, psychosocial well-being, and role performance. The domain scores had high levels of reliability (coefficient alphas ranged from 0.848 to 0.940). Validity was supported by high correlations between National Eye Institute Visual Function Questionnaire scales and the new-vision-targeted scales (highest values were 0.771 between psychosocial well-being and mental health, and 0.729 between role performance and role difficulties), and by lower mean scores in those groups self-reporting eye disease (F statistic with p < 0.01 for all comparisons except cataract with ocular symptoms, psychosocial well-being, and role performance scales).

CONCLUSIONS

This vision-targeted HRQOL measure provides a basis for comprehensive assessment of the impact of eye diseases and treatments on daily functioning and well-being in adults.

Vision assessment using the NIH Toolbox

Vision is a sensation that is created from complex processes and provides us with a representation of the world around us. There are many important aspects of vision, but visual acuity was judged to be the most appropriate vision assessment for the NIH Toolbox for Assessment of Neurological and Behavioral Function, both because of its central role in visual health and because acuity testing is common and relatively inexpensive to implement broadly. The impact of visual impairments on health-related quality of life also was viewed as important to assess, in order to gain a broad view of one's visual function. To test visual acuity, an easy-to-use software program was developed, based on the protocol used by the E-ETDRS. Children younger than 7 years were administered a version with only the letters H, O, T, and V. Reliability and validity of the Toolbox visual acuity test were very good. A 53-item vision-targeted, health-related quality of life survey was also developed.

Quantification of ghosting produced with presbyopic contact lens correction

OBJECTIVES

The defocused portion of the image obtained in wearers of bifocal and multifocal contact lenses often appears as a "ghost." Relatively few methods exist to quantify the ghosting perceived with lenses. The purpose of this study is to validate and implement a questionnaire to help patients quantify the ghost images perceived with bifocal or multifocal corrections.

METHODS

Ten subjects viewed simulated bifocal vision images displayed on a monitor. Images contained a focused and a defocused (ghost) component of a specific dimension (direction, position offset, intensity, and focus). Using a test card, the subjects identified the ghosting dimension level displayed on the monitor. An additional 54 presbyopic subjects wearing a multifocal correction monocularly viewed a well-focused stimulus and then compared the perceived image to that of the other well-corrected eye looking at the ghosting test card to quantify their visual experience of the 4 proposed ghosting dimensions.

RESULTS

Regardless of ghost letter size and orientation, subject responses were within 1 rating unit of expected on >95% of all trials for all 4 dimensions when asked to directly match a single dimension of ghosting. With bifocal images containing random amounts of these 4 dimensions most response errors were also within ± 1 unit. In presbyopes wearing a multifocal lens, the focus dimension was most strongly associated with overall ratings of ghosting.

CONCLUSIONS

The subjects can accurately and reliably report on ghost intensity, focus, direction and position offset, and well-focused ghosts are most correlated with the overall perceptual saliency of ghosting.

Towards a capabilities database to inform inclusive design: experimental investigation of effective survey-based predictors of human-product interaction

A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.

Comparison of patient-reported visual outcome methods to quantify the perceptual effects of defocus

PURPOSE

Patient-reported subjective responses have become increasingly popular in describing contact lens visual performance and discriminating between designs. The purpose of the current study is to evaluate the ability of patient-reported measures of vision to quantify the perceptual effects of defocus.

METHODS

Ten young (18-35 years) subjects rated their subjective visual performance monocularly on 3 scales following wear of their optimal monocular distance correction and nine different blurring lenses (-0.50 to +1.50 in 0.25 D steps) in a trial frame. The three scales used were a 0-100 numeric rating scale (NRS), a 100 mm visual analog scale (VAS), and a 5 point ("Poor", "Fair", "Average", "Good", "Excellent") categorical rating scale (CRS).

RESULTS

Mixed linear modeling results found no significant effects either for eye or trial number, but did find a significant effect due to blurring lens power (p<0.0001), with ratings decreasing with increasing levels of blur for all scales. Results were not significantly different between the NRS and VAS at any level of blur, with limits of agreement falling within 22% of the measurement scale. CRS ratings were about 15 units lower than the other scales on average, with limits of agreement that varied with lens power and were roughly 3 times as large. Across scale internal consistency was 0.94.

CONCLUSIONS

The NRS and VAS yield virtually identical rating responses, but both differing slightly, however from the CRS. Each scale successfully discriminated levels of blur smaller than 0.25 D with only a single measurement.

Pre-validation methods for developing a patient reported outcome instrument

Background

Measures that reflect patients' assessment of their health are of increasing importance as outcome measures in randomised controlled trials. The methodological approach used in the pre-validation development of new instruments (item generation, item reduction and question formatting) should be robust and transparent. The totality of the content of existing PRO instruments for a specific condition provides a valuable resource (pool of items) that can be utilised to develop new instruments. Such 'top down' approaches are common, but the explicit pre-validation methods are often poorly reported. This paper presents a systematic and generalisable 5-step pre-validation PRO instrument methodology.

Methods

The method is illustrated using the example of the Aberdeen Glaucoma Questionnaire (AGQ). The five steps are: 1) Generation of a pool of items; 2) Item de-duplication (three phases); 3) Item reduction (two phases); 4) Assessment of the remaining items' content coverage against a pre-existing theoretical framework appropriate to the objectives of the instrument and the target population (e.g. ICF); and 5) qualitative exploration of the target populations' views of the new instrument and the items it contains.

Results

The AGQ 'item pool' contained 725 items. Three de-duplication phases resulted in reduction of 91, 225 and 48 items respectively. The item reduction phases discarded 70 items and 208 items respectively. The draft AGQ contained 83 items with good content coverage. The qualitative exploration ('think aloud' study) resulted in removal of a further 15 items and refinement to the wording of others. The resultant draft AGQ contained 68 items.

Conclusions

This study presents a novel methodology for developing a PRO instrument, based on three sources: literature reporting what is important to patient; theoretically coherent framework; and patients' experience of completing the instrument. By systematically accounting for all items dropped after the item generation phase, our method ensures that the AGQ is developed in a transparent, replicable manner and is fit for validation. We recommend this method to enhance the likelihood that new PRO instruments will be appropriate to the research context in which they are used, acceptable to research participants and likely to generate valid data.

Patient-reported outcomes (PRO's) in glaucoma: a systematic review

The aim of this review was to summarize literature in view of patient-reported outcome (PRO) instruments for glaucoma and provide guidance on how outcomes are best assessed based on evidence about their content and validity. A systematic literature review was performed on papers describing the developmental process and/or psychometric properties of glaucoma or vision-specific PRO-instruments. Each of them was assessed on their adherence to a framework of quality criteria. Fifty-three articles were identified addressing 27 PRO-instruments. In all, 18 PRO's were developed for glaucoma and 9 for diverse ophthalmologic conditions. Seven instruments addressed functional status, 11 instruments quality of life and 9 instruments disease and treatment-related factors. Most of the instruments demonstrated only partially adherence to predefined quality standards. The tools for assessing functional status were of poor quality, while the Glaucoma Quality of Life Questionnaire and the Vision Quality of Life Index were well-developed QoL measures, yet only validated using classical techniques. The Rasch-scaled QoL-tools, IVI and VCM1 need to improve their item-content for glaucoma patients. The questionnaires to measure adherence should improve their validity and the Treatment Satisfaction Survey for Intra Ocular Pressure pops out as the highest quality tool for measuring topical treatment side effects. This review revealed that most PRO-instruments demonstrated poor developmental quality, more specifically a lack of conceptual framework and item generation strategies not involving the patients' perspective. Psychometric characteristics were mostly tested using classical validation techniques.

Choosing appropriate patient-reported outcomes instrument for glaucoma research: a systematic review of vision instruments

PURPOSE

To identify vision Patient-Reported Outcomes instruments relevant to glaucoma and assess their content validity.

METHODS

MEDLINE, MEDLINE in Process, EMBASE and SCOPUS (to January 2009) were systematically searched. Observational studies or randomised controlled trials, published in English, reporting use of vision instruments in glaucoma studies involving adults were included. In addition, reference lists were scanned to identify additional studies describing development and/or validation to ascertain the final version of the instruments. Instruments' content was then mapped onto a theoretical framework, the World Health Organization International Classification of Functioning, Disability and Health. Two reviewers independently evaluated studies for inclusion and quality assessed instrument content.

RESULTS

Thirty-three instruments were identified. Instruments were categorised into thirteen vision status, two vision disability, one vision satisfaction, five glaucoma status, one glaucoma medication related to health status, five glaucoma medication side effects and six glaucoma medication satisfaction measures according to each instruments' content. The National Eye Institute Visual Function Questionnaire-25, Impact of Vision Impairment and Treatment Satisfaction Survey-Intraocular Pressure had the highest number of positive ratings in the content validity assessment.

CONCLUSION

This study provides a descriptive catalogue of vision-specific PRO instruments, to inform the choice of an appropriate measure of patient-reported outcomes in a glaucoma context.

Vision-related quality of life in first stroke patients with homonymous visual field defects

Background

To evaluate vision-related and health-related quality of life (VRQoL, HRQoL) in first stroke patients with homonymous visual field defects (VFD) with respect to the extent of the lesion. Since VFD occur in approximately 10% of stroke patients the main purpose of the study was to investigate the additional impact of VFD in stroke patients hypothesizing that VFD causes diminished VRQoL.

Methods

In 177 first stroke patients with persisting VFD 2.5 years after posterior-parietal lesions VRQoL was assessed by the National-Eye-Institute-Visual-Functioning-Questionnaire (NEI-VFQ) and HRQoL by the Medical-Outcome-Study Short-Form-36 Health-Survey (SF-36). Questionnaire results of VFD-patients were compared with age- and sex-matched healthy controls and with general non-selected stroke samples as published elsewhere. VFD-type and visual acuity were partially correlated with questionnaire results.

Results

Compared to healthy controls VFD-patients had lower NEI-VFQ scores except ocular pain (Z-range -11.34 to -3.35) and lower SF-36 scores except emotional role limitations (Z-range -7.21 to -3.34). VFD-patients were less impaired in SF-36 scores than general stroke patients one month post lesion (6/8 subscales) but had lower SF-36 scores compared to stroke patients six months post lesion (5/8 subscales). Visual acuity significantly correlated with NEI-VFQ scores (r-range 0.27 to 0.48) and VFD-type with SF-36 mental subscales (r-range -0.26 to -0.36).

Conclusions

VFD-patients showed substantial reductions of VRQoL and HRQoL compared to healthy normals, but better HRQoL compared to stroke patients one month post lesion. VFD-patients (although their lesion age was four times higher) had significantly lower HRQoL than a general stroke population at six months post-stroke. This indicates that the stroke-related subjective level of HRQoL impairment is significantly exacerbated by VFD. While VRQoL was primarily influenced by visual acuity, mental components of HRQoL were influenced by VFD-type with larger VFD being associated with more distress.

The impact of test medium on use of visual analogue scales

OBJECTIVES

Visual analog scales are frequently used as a means of allowing participants to rate symptoms during clinical trials. The accuracy and reproducibility of these scales play an important role in determining the experimental value of the data they provide. This study was initiated to compare the data collected using paper- and computer-based (Tablet PC) analog scales to better understand the variability in data provided by a visual analog scale.

METHODS

Thirty participants rated ocular comfort, redness, and clarity of vision (right and left eyes) on a nondemarcated horizontal line on both paper and a Tablet PC. Measurements were taken in the morning between the hours of 8:30 and 10:30 am and again the same day between 2:30 and 4:30 pm.

RESULTS

The mean difference between the measures recorded in the morning for the 2 media was 2.6 +/- 0.9 (confidence intervals, 2 standard errors of the differences) units on a 100 unit scale, with the Tablet PC having the higher mean measure. The limits of agreement (2 standard deviations of the differences) was 9.4 units. Comparing the difference of the differences (1.0 +/- 1.3) between the 2 methods of measure (morning vs. afternoon) the visual analog scales on the Tablet PC seemed to have good reproducibility of agreement in comparison with the paper version.

CONCLUSIONS

Discrepancy analysis yielded no significant difference and slight bias between paper- and computer-based analog scales. Repeatability of measures using the Tablet PC was also demonstrated. These results suggest that the choice of medium does not significantly influence the outcome for subjective analog scales.

Vision-related quality of life and visual function after retinal detachment surgery

PURPOSE

To compare the vision-related quality of life (VR QOL) after rhegmatogenous retinal detachment (RD) surgery with that of normal controls and to investigate the relationship between the VR QOL and visual function after surgery for RD.

DESIGN

Prospective, consecutive, comparative case series.

METHODS

The 25-Item National Eye Institute Visual Function Questionnaire (VFQ-25) was self-administered by 51 RD patients at six months after surgery. Among the patients with RD, 33 underwent pars plana vitrectomy and 18 received scleral buckling. We examined the logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA), contrast sensitivity with the CSV-1000E (Vector Vision Co, Greenville, Ohio, USA), and low-contrast visual acuity (VA) with the CSV-1000LanC10% (Vector Vision Co). From the data obtained by CSV-1000E, the area under the log contrast sensitivity function (AULCSF) was calculated. The VFQ-25 also was administered to the 46 age-matched normal controls.

RESULTS

The VFQ-25 composite score and the subscales associated with near activities, mental health, dependency, and peripheral vision were significantly lower in the RD group than in the normal controls (P < .05). The VFQ-25 composite score significantly correlated with AULCSF (r = 0.354; P < .05) and low-contrast VA (r = -0.475; P < 0.001), whereas there was no correlation between the VFQ-25 composite score and logMAR BCVA (r = 0.172; P = .229).

CONCLUSIONS

The VR QOL is significantly impaired in patients after surgery for RD. The disturbance in VR QOL was significantly associated with deterioration of postoperative contrast sensitivity.

Evaluation of cross-sectional and longitudinal construct validity of two vision-related quality of life questionnaires: the LVQOL and VCM1

The Low Vision Quality of Life (LVQOL) questionnaire and the Vision-related Quality of Life Core Measure (VCM1) are two of the many vision-related quality of life (QOL) questionnaires that have been developed in recent years. Although psychometric properties of the LVQOL and VCM1 compare well with other vision-related QOL questionnaires, construct and longitudinal validity have not been assessed (adequately). The purpose of this study was to examine the cross-sectional and longitudinal construct validity of these questionnaires by testing specific pre-specified hypotheses about the relations of these questionnaires with other measures. The percentage of hypotheses regarding the cross-sectional construct validity that were refuted for the LVQOL was 22% for the basic aspects of vision subscale, 50% for the mobility subscale, 39% for the adjustment subscale and 17% for the reading and fine work subscale. For the VCM1 this percentage was 57%. For the longitudinal construct validity the percentage of hypotheses that were refuted ranged from 33 to 75% for the LVQOL subscales and was 50% for the VCM1. In conclusion, cross-sectional construct validity was satisfactory for the LVQOL subscales, but seemed poor for the VCM1. In addition, the longitudinal validity of these scales was poor to moderate.

Visual function and dysfunction in early and late age-related maculopathy

Late age-related maculopathy (ARM) is responsible for the majority of blind registrations in the Western world among persons over 50 years of age. It has devastating effects on quality of life and independence and is becoming a major public health concern. Current treatment options are limited and most aim to slow progression rather than restore vision; therefore, early detection to identify those patients most suitable for these interventions is essential. In this work, we review the literature encompassing the investigation of visual function in ARM in order to highlight those visual function parameters which are affected very early in the disease process. We pay particular attention to measures of acuity, contrast sensitivity (CS), cone function, electrophysiology, visual adaptation, central visual field sensitivity and metamorphopsia. We also consider the impact of bilateral late ARM on visual function as well as the relationship between measures of vision function and self-reported visual functioning. Much interest has centred on the identification of functional changes which may predict progression to neovascular disease; therefore, we outline the longitudinal studies, which to date have reported dark-adaptation time, short-wavelength cone sensitivity, colour-match area effect, dark-adapted foveal sensitivity, foveal flicker sensitivity, slow recovery from glare and slower foveal electroretinogram implicit time as functional risk factors for the development of neovascular disease. Despite progress in this area, we emphasise the need for longitudinal studies designed in light of developments in disease classification and retinal imaging, which would ensure the correct classification of cases and controls, and provide increased understanding of the natural course and progression of the disease and further elucidate the structure-function relationships in this devastating disorder.

Contrast sensitivity as an outcome measure in patients with subfoveal choroidal neovascularisation due to age-related macular degeneration

PURPOSE

Although visual acuity is the most frequently used primary outcome measure in clinical trials of treatments for choroidal neovascularisation (CNV) due to age-related macular degeneration (AMD), contrast sensitivity may provide valuable additional information. This paper reviews the evidence for using contrast sensitivity as a measure of visual function and as an outcome measure in clinical trials in patients with subfoveal CNV due to AMD.

METHODS

Medline database searches were performed to retrieve relevant articles on contrast sensitivity. In addition, articles were included from the authors' knowledge of the literature and from the reference lists of retrieved articles.

RESULTS

The published literature demonstrates that contrast sensitivity is an important measure of visual function in patients with subfoveal CNV due to AMD. Most clinical trials of treatments for CNV due to AMD have reported visual acuity as the primary outcome. However, there is evidence that treatment (such as verteporfin therapy) may also provide additional benefits in terms of contrast sensitivity. These benefits may not be completely characterised by measurement of visual acuity alone.

CONCLUSIONS

The inclusion of contrast sensitivity as an outcome measure in studies of patients with CNV due to AMD may provide a more complete understanding of the effects of treatment on visual function and the likely benefits for patients.

A Nationwide Population-Based Survey on Visual Acuity, Near Vision, and Self-Reported Visual Function in the Adult Population in Finland

PURPOSE

To estimate the prevalence rates of habitual visual acuity (VA) levels and visual impairment in Finland and to assess their correlation with self-reported visual function.

DESIGN

Cross-sectional population-based study.

PARTICIPANTS

Subjects were selected randomly from the Finnish population aged 30 years or older. Of 7979 eligible people, 7393 (93%) were interviewed, 6771 (85%) were examined, and 6663 (84%) had distance VA assessed.

METHODS

Participants underwent a home interview and a comprehensive examination including measuring binocular VA for distance and for near with the participants' current spectacles, if any.

MAIN OUTCOME MEASURES

The level of VA for distance and for near with current spectacle correction. The self-reported capability to read newsprint and television text and the ability to move about without being restricted by reduced vision.

RESULTS

The prevalence of good to moderate VA for distance (VA> or =0.5 [> or =20/40]) measured with current spectacles was 95.9%, and 87.4% had a VA level of 0.8 (20/25) or better. The prevalence of habitual visual impairment (VA< or =0.25 [< or =20/80]) was 1.6%, and 0.5% were blind (VA<0.1 [<20/200]). The prevalence of visual impairment increased significantly with age (P<0.001), especially in the age group of 65 to 74 years and upward. There was no gender difference in VA for distance, but decreased near vision (VA< or =0.25 [< or =20/80]) was significantly more common in men than in women (P<0.01). By applying the imputated numbers of visually impaired and blind participants to the Finnish population (approximately 3 million aged 30 years or older), there were approximately 65000 (2.1%) visually impaired and 17000 (0.6%) blind adult persons in the country in 2000. The correlation between self-reported visual ability and measured visual function was moderate but statistically significant (r = 0.27-0.40; P<0.0001). The proportion of people with reading difficulties or who were unable to read newsprint has decreased 7% during the last 2 decades.

CONCLUSIONS

Functional visual impairment increased with age especially in the age group of 65 to 74 years and upward and was as prevalent in women as in men. The prevalence of people with reading difficulties has decreased considerably since 1980.

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.

Assessment of visual satisfaction and function after cataract surgery

PURPOSE

To examine the relationships between importance, satisfaction, visual acuity, and visual function in a sample of preoperative cataract patients and to derive and prospectively evaluate a shortened measure of visual function.

SETTING

Day-stay cataract surgery unit at large private hospital and consulting rooms of metropolitan ophthalmologists.

METHODS

Two independent samples of 111 and 121 patients were surveyed before and after surgery with regard to their visual satisfaction, trouble with vision, VF-14 visual function, overall satisfaction, and importance of factors affecting patient satisfaction. A 7-item scale of visual function derived from the first sample's results was prospectively tested against the second sample. Distance and reading acuities were recorded from the patients' charts.

RESULTS

The 7-item measure of visual function strongly correlated with the VF-14 (r>0.9) and had predictive power equal to that of the VF-14 for satisfaction and trouble with vision. However, the 7 items differed somewhat from a version developed in Helsinki. Distance visual acuity was not significantly correlated with visual function, satisfaction, or trouble with vision, although reading acuity was significantly correlated with visual function and trouble with vision (r=0.31 and r=0.32, respectively).

CONCLUSIONS

A shortened measure of visual function that had a predictive value equal to that of the VF-14 can more practically be used in everyday practice. Furthermore, the study showed that regional factors matter and highlights the necessity of basing measurement scales on factors important to the population in question to ensure scale validity.

A comparison of findings on parents' and teachers' questionnaires, and detailed ophthalmic and psychological assessments

BACKGROUND

Questionnaires are important tools used to gain information about health and level of function in different domains.

AIMS AND METHODS

To determine the degree of agreement between questionnaires, administered to parents and teachers, and ophthalmic and psychological examinations in a cohort of 309 low birth weight children (<1701 g) at age 10-13 years.

RESULTS

A total of 90.9% of cases showed agreement between the question on distance vision and clinical assessment, and agreement for the near vision question was 83%. However, the correlation on an individual basis was only fair (kappa = 0.46, distance vision) to poor (kappa = 0.2, near vision). The overall agreement for the questions on cognitive ability was better than the correlation, whereas the questions on reading and mathematical ability showed low agreement and low correlation.

CONCLUSION

Questionnaire assessment of vision and cognitive ability is more suitable for studying the outcome of a large population than for identifying deficits in individuals.

Baseline characteristics, the 25-Item National Eye Institute Visual Functioning Questionnaire, and their associations in the Complications of Age-Related Macular Degeneration Prevention Trial (CAPT)

OBJECTIVE

To describe characteristics of participants in the Complications of Age-Related Macular Degeneration Prevention Trial (CAPT) at baseline and to investigate associations among visual function, fundus features, and vision-related quality of life.

DESIGN

Cross-sectional study.

PARTICIPANTS

The 1052 participants in CAPT, a multicenter, randomized clinical trial. Eligibility criteria for CAPT included > or =10 large drusen and visual acuity > or =20/40 in each eye.

METHODS

At baseline, the visual acuity, contrast sensitivity, and critical print size for each eye were measured, color stereo photographs of the disc and macula of each eye were taken, and the 25-item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) was self-administered. Graders from a central photograph reading center evaluated the photographs for drusen characteristics and focal hyperpigmentation. All procedures were performed using standardized protocols. Associations among characteristics were assessed by Spearman correlation coefficients and multiple linear regression.

RESULTS

Among CAPT participants at baseline, the mean age was 71.0 years, 60.6% were women, and 99.3% were white. The median visual acuity of the better eye was 20/20 and of the worse eye 20/25. In approximately one third of eyes, drusen covered > or =10% of the retina within 3000 microm of the foveal center, and 67.7% of eyes had focal hyperpigmentation. Drusen area and focal hyperpigmentation were weakly correlated (r = -0.08 to -0.18) with the measures of visual function. The measures of visual function were weakly associated with the NEI-VFQ-25 scores. An association of fundus features with NEI-VFQ-25 scores was not found.

CONCLUSION

At baseline, CAPT participants had good visual function and several risk factors for progression to neovascular age-related macular degeneration. Scores on the NEI-VFQ-25 indicated that participants perceived some problems with their vision. Within this relatively homogeneous group of participants, measures of visual function were only weakly associated with the measures of vision-related quality of life.