| 1. |
- Cima, Joana, et al.
(författare)
-
EQ-5D and Activity Inventory : Measures of Visual Health Outcome
- 2015
-
Ingår i: European Journal of Public Health. - : Oxford University Press (OUP). - 1101-1262 .- 1464-360X. ; 25:Suppl 3
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the study is to test if EQ-5D, a more generic instrument, and Activity Inventory, a more specific instrument to the visual condition, produce consistent results when considering the different levels of visual impairment. By assessing how these instruments reflect visual status in a sample of patients with visual impairment, we will help to understand how they can work in cultural context and population in which they were never tested before.Method is based on Multivariate Analysis of Variance, in which the levels of visual impairment (slightly, moderate, severe/blindness) are defined through the visual acuity values, and the utility values derived from EQ-5D and the Activity Inventory.Participants were recruited in 3 public hospitals as a part of an ongoing study of prevalence and costs of visual impairment in Portugal. Patients attending outpatient appointments in these hospitals with acuity in the better eye of 0,30logMAR or worse and/or visual field in the better eye <20 degrees were invited to take part in face-to-face interviews. Additional visual measures, as acuity was collected using standardize methods. Visual acuity was assessed using an internally illuminated ETDRS chart at 4 m with room lights extinguished.The results show that both instruments have a good explanatory power. However when considering different clinical conditions, the AI presents better results. The EQ-5D due its low sensitivity/adaptability does not capture differences in health status in patients with slightly and moderate visual impairment.Since EQ-5D is the instrument most used in the evaluation of public health programs performance, the results suggest that its use should be more cautious in a situation of different difficulty levels. The results indicate that in these cases the EQ-5D should be used with a complementary instrument more specific to the clinical condition.Key messagesThe results suggest that with different difficulty levels the EQ-5D should be used with a complementary instrument more specific to the clinical condition to be produced more reliable resultsThis study is supported by the Portuguese Foundation for Science and Technology (FCT) -POCTI & FSE GRANT: PTDC/DPT-EPI/0412/2012
|
|
| 2. |
- Goncalves Fernandes Ferreira, Flavio Pedro, et al.
(författare)
-
Artificial eye for calibration of an eye-tracker, eye tracking calibration system and method thereof
- 2021
-
Patent (populärvet., debatt m.m.)abstract
- Abstract(EN) An artificial eye for eye tracking calibration of an eye-tracker, comprising: an eye model comprising a foveal region; an optical position sensor arranged at the foveal region for transducing the position of a foveal light spot into a sensor position signal; a two-axis rotational pivoting support upon which the eye model is mounted; a two-axis actuator for rotating the eye model in said pivoting support; a feed-back electronic circuit, connected between the sensor and actuator, arranged to cause rotation of the eye model by said actuator such that the sensor position signal matches a reference position signal. The reference position signal may be adjustable to cause an off-set between the pupillary-axis of the eye model and a visual-axis defined by the reference position signal, in particular the reference position signal being adjustable by configuration of the feed-back electronic circuit.(FR) L'invention concerne un oeil artificiel pour l'étalonnage de suivi de l'oeil d'un oculomètre, comprenant : un modèle d'oeil comprenant une région fovéale ; un capteur de position optique disposé au niveau de la région fovéale pour convertir la position d'un point lumineux fovéal en un signal de position de capteur ; un support pivotant rotatif à deux axes sur lequel est monté le modèle oculaire ; un actionneur à deux axes pour faire tourner le modèle d'oeil dans ledit support pivotant ; un circuit électronique de rétroaction, connecté entre le capteur et l'actionneur, agencé pour provoquer la rotation du modèle d'oeil par ledit actionneur de telle sorte que le signal de position de capteur corresponde à un signal de position de référence. Le signal de position de référence peut être réglé pour provoquer un décalage entre l'axe pupillaire du modèle d'oeil et un axe visuel défini par le signal de position de référence, en particulier le signal de position de référence étant réglable par la configuration du circuit électronique de rétroaction.
|
|
| 3. |
- Macedo, António Filipe, 1976-, et al.
(författare)
-
An exploratory study of temporal integration in the peripheral retina of myopes
- 2017
-
Ingår i: Proceedings of SPIE 10453. - : SPIE - International Society for Optical Engineering. - 9781510613843 - 9781510613836
-
Konferensbidrag (refereegranskat)abstract
- The visual system takes time to respond to visual stimuli, neurons need to accumulate information over a time span in order to fire. Visual information perceived by the peripheral retina might be impaired by imperfect peripheral optics leading to myopia development. This study explored the effect of eccentricity, moderate myopia and peripheral refraction in temporal visual integration. Myopes and emmetropes showed similar performance at detecting briefly flashed stimuli in different retinal locations. Our results show evidence that moderate myopes have normal visual integration when refractive errors are corrected with contact lens; however, the tendency to increased temporal integration thresholds observed in myopes deserves further investigation.
|
|
| 4. |
- Macedo, António Filipe, Senior Lecturer, 1976-, et al.
(författare)
-
Predictors of problems reported on the EQ-5D-3L dimensions among people with impaired vision in northern Portugal
- 2022
-
Ingår i: Health and Quality of Life Outcomes. - : BioMed Central (BMC). - 1477-7525. ; 20:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background:The EQ-5D index often fails to detect the effect of ophthalmic diseases and sight loss. Investigating predictors of individual EQ-5D health dimensions might reveal the underlying reasons. The aim of this study was to investigate predictors of health dimension ratings obtained with the EQ-5D-3L from participants with impaired vision representing a spectrum of eye diseases.Methods: Observational cross-sectional study with participants recruited at four public hospitals in Portugal. Outpatients with visual acuity of 0.30 logMAR(6/12) or worse in the better-seeing eye were invited to participate. Participants completed two instruments: the EQ-5D-3L (measures participants’ perceived health-related quality-of-life) and the Massof Activity Inventory (measures visual ability–ability to perform vision-related activities). This study used logistic regression models to identify factors associated with responses to the EQ-5D-3L.Results: The study included 492 participants, mean age 63.4 years (range = 18–93), 50% females. The most common diagnosis was diabetic retinopathy (37%). The mean visual acuity in the better seeing eye was 0.65 logMAR (SD = 0.48) and the mean visual ability was 0.62 logits (SD = 2.04), the correlation between the two was r = − 0.511 (p < 0.001). Mobility and self-care were the health dimensions with the fewest problems (1% reported extreme problems), anxiety and depression the dimension with the most problems (24% reported extreme problems). ROC curve analysis showed that the EQ-5D index was a poor predictor of cases of vision impairment whilst visual ability given was a good predictor of cases of vision impairment. Visual ability was an independent predictor of the response for all dimensions, higher ability was always associated with a reduced odds of reporting problems. The odds of reporting problems were increased for females in 3 out of 5 dimensions. Comorbidities, visual acuity and age-category were predictors of the odds of reporting problems for one dimension each.Conclusions: The odds of reporting problems for the five health dimensions of the EQ-5D-3L were strongly influenced by the ability to perform vision-related activities (visual ability). The EQ-5D index showed poor performance at detecting vision impairment. These findings are informative and relevant for the clinic and for research evaluating the impact of eye diseases and disease treatments in ophthalmology.
|
|
| 5. |
- Miranda, Antonio Miguel, et al.
(författare)
-
Eye movements, convergence distance and pupil-size when reading from smartphone, computer, print and tablet
- 2018
-
Ingår i: Scandinavian Journal of Optometry and Visual Science. - : The Norwegian Association of Optometry. - 1891-0882 .- 1891-0890. ; 11:1, s. 1-5
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated the use of eye-tracking glasses to monitor visual behaviour when reading from electronic devices and paper in free-viewing conditions. The Tobii-Pro-Glasses were used to monitor 20 subjects with normal vision during reading tasks. Reading was performed in a smartphone, computer, paper and tablet. Texts from the IReST-test were read in devices in a random order. Participants read one text in each device and then repeated the same task 1 hour later; in total each participant read eight different texts. The sequence for the devices was randomized. We found differences between devices for saccade amplitude, fixation duration, convergence distance and pupil size. Reading speed between computer and tablet was slightly different (8 words-per-minute) and pupil size reduced up to 20% in electronic devices compared to print. Behavioural changes observed whilst reading from different devices may reflect an attempt from readers to optimize performance. The need to maintain visual performance under different visual condition may lead to increased visual symptoms. Eye-tracking glasses could be a valuable tool to investigate visual aspects of digital strain.
|
|
| 6. |
|
|
| 7. |
- Baskaran, Karthikeyan, Senior Lecturer, 1983-, et al.
(författare)
-
Reading performance in Portuguese children from second to tenth grade with the MNREAD reading acuity test
- 2023
-
Ingår i: Journal of Optometry. - : Elsevier. - 1888-4296. ; 16:4, s. 261-267
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeTo assess reading performance and report normative values for normal sighted Portuguese schoolchildren using the Portuguese version of the MNREAD reading acuity chart.MethodsChildren in the 2nd, 4th, 6th, 8th, and 10th grade in Portugal were recruited for this study. One hundred and sixty-seven children from 7 to 16 years of age participated. The Portuguese version of the printed MNREAD reading acuity chart was used to measure reading performance in these children. The non-linear mixed effects model with negative exponential decay function was used to compute maximum reading speed (MRS) and critical print size (CPS) automatically. Reading acuity (RA) and reading accessibility index (ACC) were computed manually.ResultsThe mean MRS in words-per-minute (wpm) for the 2nd grade was 55 wpm (SD = 11.2 wpm), 104 wpm (SD = 27.9) for the 4th grade, 149 wpm (SD = 22.5) for 6th grade, 172 wpm (SD = 24.6) for 8th grade and 180 wpm for the 10th grade (SD = 16.8). There was a significant difference in MRS between school grades (p < 0.001). Participants’ reading speed increased by 14.5 wpm (95% CL: 13.1–15.9) with each year of increase in age. We found a significant difference between RA and school grades, but not for CPS.ConclusionsThis study provides normative reading performance values for the Portuguese version of the MNREAD chart. The MRS increased with increasing age and school grade, while RA shows initial improvement from early school years and gradually stabilizes in the more mature children. Normative values for the MNREAD test can now be used to determine reading difficulties or slow reading speed in, for example, children with impaired vision.
|
|
| 8. |
- Baskaran, Karthikeyan, Senior Lecturer, 1983-, et al.
(författare)
-
Scoring reading parameters : An inter-rater reliability study using the MNREAD chart
- 2019
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 14:6, s. 1-14
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose First, to evaluate inter-rater reliability when human raters estimate the reading performance of visually impaired individuals using the MNREAD acuity chart. Second, to evaluate the agreement between computer-based scoring algorithms and compare them with human rating. Methods Reading performance was measured for 101 individuals with low vision, using the Portuguese version of the MNREAD test. Seven raters estimated the maximum reading speed (MRS) and critical print size (CPS) of each individual MNREAD curve. MRS and CPS were also calculated automatically for each curve using two different algorithms: the original standard deviation method (SDev) and a non-linear mixed effects (NLME) modeling. Intra-class correlation coefficients (ICC) were used to estimate absolute agreement between raters and/or algorithms. Results Absolute agreement between raters was ‘excellent’ for MRS (ICC = 0.97; 95%CI [0.96, 0.98]) and ‘moderate’ to ‘good’ for CPS (ICC = 0.77; 95%CI [0.69, 0.83]). For CPS, inter-rater reliability was poorer among less experienced raters (ICC = 0.70; 95%CI [0.57, 0.80]) when compared to experienced ones (ICC = 0.82; 95%CI [0.76, 0.88]). Absolute agreement between the two algorithms was ‘excellent’ for MRS (ICC = 0.96; 95%CI [0.91, 0.98]). For CPS, the best possible agreement was found for CPS defined as the print size sustaining 80% of MRS (ICC = 0.77; 95%CI [0.68, 0.84]). Absolute agreement between raters and automated methods was ‘excellent’ for MRS (ICC = 0.96; 95% CI [0.88, 0.98] for SDev; ICC = 0.97; 95% CI [0.95, 0.98] for NLME). For CPS, absolute agreement between raters and SDev ranged from ‘poor’ to ‘good’ (ICC = 0.66; 95% CI [0.3, 0.80]), while agreement between raters and NLME was ‘good’ (ICC = 0.83; 95% CI [0.76, 0.88]). Conclusion For MRS, inter-rater reliability is excellent, even considering the possibility of noisy and/or incomplete data collected in low-vision individuals. For CPS, inter-rater reliability is lower. This may be problematic, for instance in the context of multisite investigations or follow-up examinations. The NLME method showed better agreement with the raters than the SDev method for both reading parameters. Setting up consensual guidelines to deal with ambiguous curves may help improve reliability. While the exact definition of CPS should be chosen on a case-by-case basis depending on the clinician or researcher’s motivations, evidence suggests that estimating CPS as the smallest print size sustaining about 80% of MRS would increase inter-rater reliability.
|
|
| 9. |
- Baskaran, Karthikeyan, Senior Lecturer, 1983-, et al.
(författare)
-
Scoring reading parameters: an inter-rater reliability study using the MNREAD test
- 2017
-
Konferensbidrag (refereegranskat)abstract
- Aim: Estimating MNREAD parameters such as Critical Print Size (CPS) and Maximum Reading Speed (MRS) - using the time taken to read blocks of text - often requires subjective analysis of the reading profile. Depending on the rater, parameters may be over- or under-estimated, resulting in difficult or even impossible between-study comparisons. The aim of this project was to evaluate the inter-rater reliability of MNREAD parameters in subjects with visual impairment. Methods: Reading times for the Portuguese version of the MNREAD chart from 32 subjects, reading binocularly were analyzed. Reading speed was computed by a single experimenter (AFM) using reading time and number of errors. Based on reading speeds, three experimented raters (AFM, AC and KB) computed MRS and CPS using the following method. CPS was defined as the print size at which subsequent smaller print sizes were read at 1.96 x standard deviation slower than the mean of the preceding print sizes; MRS was estimated as the mean reading speed for sentences in print larger than the CPS. Inter-rater reliability was assessed using intra-class correlation (ICC) coefficient for both MRS and CPS for all three raters. Results: Near acuity range was 0.14-1.9 logMAR. The average measure ICC for CPS was 0.896 with a 95% CI from 0.814 to 0.946 (p< 0.001). The average measure ICC for MRS was 0.984 with a 95% CI from 0.970 to 0.992 (p< 0.001). Conclusion: A high degree of reliability was found between the three raters for both CPS and MRS. Even though some small variability exists this may be due to raters’ high-level experience with MNREAD data. Future directions will involve: 1) including more raters with various level of experience in MNREAD rating; 2) investigating the degree of inter-rater reliability for raters using different estimation methods.
|
|
| 10. |
- Baskaran, Karthikeyan, Senior Lecturer, 1983-, et al.
(författare)
-
Swedish version of the Massof activity inventory to measure vision-related activity difficulties among patients with nAMD
- 2024
-
Ingår i: Acta Ophthalmol, vol 102, issue S279: Special Issue:Abstracts from the 2023 European Association for Vision and Eye Research Festival, 26‐28 October 2023, Valencia. - : John Wiley & Sons.
-
Konferensbidrag (refereegranskat)abstract
- Aims/Purpose: The aim of this study was to assess vision-related activity difficulties among patients with neovascular AMD using a Swedish version of the mass of activity inventory (MAI). Methods: Participants were patients diagnosed with neovascular AMD receiving treatment for the disease in a hospital in southeast Sweden. Participants completed the Swedish version of the MAI questionnaire. MAI can be used to measure the overall visual ability and visual ability in 4 functional domains: reading, mobility, visual motor function and visual information processing. Best corrected distance and near visual acuity (VA) were also measured. Results: Among the 196 participants (mean age=78.5 years, SD=7.67, 66% female) the median VA in the better seeing eye was 0.18 logMAR (IQR=?0.34), and in the worse eye was 0.54 logMAR (IQR=0.98). The median visual ability for all participants was 1.92 logits (IQR=2.69). There was a significant negative correlation between distance VA in the better eye and visual ability (rho=0.4025, p<0.01). Using ROC curves, we tested the capacity of the MAI to detect cases of any vision impairment (VA worse than 0.3 logMAR in the better seeing eye), the area under the curve (AUC) was 0.717 (95% CI=0.643 - 0.791 p<0.001). When we tested for detection of moderate vision impairment (VA worse than 0.5 logMAR in the better seeing eye) the AUC was 0.738 (95% CI=0.648 - 0.829 p?<0.001). Conclusions: The results indicate that the Swedish version of the MAI produce measures of visual ability that are consistent with clinical measures among patients with nAMD. The Swedish version of the MAI can be used as outcome measure in interventions for people with nAMD.References1. Macedo, A.F. et al. Predictors of problems reported on the EQ-5D-3L dimensions among people with impaired vision in northern Portugal. Health Qual Life Outcomes 2022; 20: 132.
|
|
