To evaluate the effect of residual amblyopia on functional vision and eye-related quality of life (ER-QOL) in children and their families using the Pediatric Eye Questionnaire (PedEyeQ).
Prospective cross-sectional study.
Seventeen children with residual amblyopia (no current treatment except glasses), 48 visually normal controls without glasses, and 19 controls wearing glasses (aged 8-11 years) completed the Child 5-11 year PedEyeQ. One parent for each child completed the Proxy 5-11 PedEyeQ, Parent PedEyeQ. Rasch-calibrated domain scores were calculated for each questionnaire domain and compared between amblyopic children and controls.
PedEyeQ scores were significantly lower (worse) for children with residual amblyopia than for controls without glasses across all domains: Child PedEyeQ greatest mean difference 18 points worse on Functional vision domain (95% confidence interval [CI] −29 to −7; P < .001); Proxy PedEyeQ greatest mean difference 31 points worse on Functional vision domain (95% CI −39 to −24; P < .001); Parent PedEyeQ greatest mean difference 34 points worse on the Worry about child’s eye condition domain (95% CI −46 to −22; P < .001). Compared with controls wearing glasses, PedEyeQ scores were lower for residual amblyopia on the Child Frustration/worry domain ( P = .03), on 4 of 5 Proxy domains ( P ≤ .05), and on 3 of 4 Parent domains ( P ≤ .05).
Residual amblyopia affects functional vision and ER-QOL in children. Parents of amblyopic children also experience lower quality of life. These data help broaden our understanding of the everyday-life impact of childhood residual amblyopia.
Amblyopia is the most common cause of reduced monocular visual acuity (VA) in children, affecting between 0.8% and 5% of children in the United States, and is associated with dysfunctions of accommodation, fixation, binocularity, vergence, reading speed, contrast sensitivity, and fine motor skills. Despite these well-documented effects of amblyopia on vision-related functioning, the everyday-life impact of amblyopia on a child and their family is poorly characterized. Most previous studies assess the impact of amblyopia treatment, but few have used eye-related or vision-specific instruments to evaluate the effects of amblyopia itself on children and their families. The aim of the present study was to assess the impact of residual amblyopia on eye-related quality of life (ER-QOL) and functional vision, comparing scores with visually normal children with and without glasses. We used the recently developed Pediatric Eye Questionnaire (PedEyeQ), developed to assess functional vision and eye-related quality of life (ER-QOL) in children with any eye condition, and also to assess the quality of life of parents of affected children. , In addition, we evaluated the impact of residual amblyopia on general health-related quality of life (HRQOL) using the Pediatric Quality of Life Inventory (PedsQL).
Institutional review board approval for this prospective cross-sectional study was obtained from Institutional Review Boards at the Mayo Clinic, Rochester, Minnesota, USA and the University of Texas Southwestern Medical Center, Dallas, Texas, USA. All procedures and data collection were conducted in a manner compliant with the Health Insurance Portability and Accountability Act and all research procedures adhered to the tenets of the Declaration of Helsinki. Written informed consent and assent was obtained according to local institutional review board requirements. Consecutive eligible children with residual amblyopia were prospectively enrolled from pediatric ophthalmology outpatient clinics at a tertiary medical center (Mayo Clinic, Rochester, Minnesota, USA), and in research clinics (Retina Foundation of the Southwest, Dallas, Texas, USA) between December 2017 and October 2019. Subjects were identified in outpatient or research clinics, referred by friends or colleagues, or identified through a recruitment flyer. The few patients who declined participation did so primarily owing to lack of time to complete the questionnaires. For all included subjects VA was assessed in each eye using age-appropriate clinical tests (testing method not standardized).
Children With Residual Amblyopia
Seventeen children aged 8-11 years, with a current diagnosis of residual, unilateral amblyopia (strabismic, anisometropic, or combined mechanism) were prospectively enrolled. Residual amblyopia met the following criteria: (1) interocular VA difference of 2 or more logMAR lines (letter optotype values converted to logMAR); (2) amblyopic-eye VA below 20/25 ; (3) a history of treatment with patching (n = 16), atropine (n = 5), binocular treatment (n = 7), vision therapy (n = 1), optical penalization (n = 1), or a combination of treatments (n = 10); (4) no treatment other than glasses for at least the past month (all other treatments having been discontinued). Any manifest strabismus was required to be <10 prism diopters by simultaneous prism cover test in refractive correction at distance and near (present in 5 of 17 [29%]). Significant coexistent eye disease was excluded ( Table 1 ).
|Residual Amblyopia (N = 17)||Visually Normal Controls Without Glasses (N = 48)||Visually Normal Controls Wearing Glasses (N = 19)|
|Sex of child, n (%)|
|Female||9 (53)||26 (54)||9 (47)|
|Median age, y||10||9||10|
|Race/ethnicity, n (%)|
|White||13 (76)||31 (65)||11 (58)|
|Hispanic/Latino||1 (6)||2 (4)||2 (11)|
|Black/African American||2 (12)||2 (4)||0 (0)|
|Other||1 (6)||10 (21)||5 (26)|
|More than 1||0 (0)||2 (4)||1 (0)|
|Not reported||0 (0)||1 (2)||0 (0)|
|Visual acuity (logMAR): median (range)|
|Amblyopic eye||0.4 (0.2 to 1.2)||NA||NA|
|Fellow eye||0.0 (−0.2 to 0.5)||NA||NA|
|Right eye||NA||0 (−0.2 to 0.1)||0 (−0.1 to 0.1)|
|Refractive error spherical equivalent: median (range)|
|Amblyopic eye||+4.50 D (+0.88 D to +9.00 D)||NA||NA|
|Fellow eye||+1.63 D (−1.50 D to +7.88 D)||NA||NA|
|Right eye||NA||NA||+0.88 D (−2.88 D to +7.00 D)|
|Cause of residual amblyopia, n (%)|
|Combined mechanism||9 (53)||NA||NA|
Visually Normal Controls
Forty-eight 8- to 11-year-old children, with no glasses or other refractive correction, normal VA for age, and no eye condition or history of an eye condition (including strabismus), were enrolled as the primary control group. Thirty-four of these control subjects were reported in previous studies.
We defined a second control group of 19 children with normal VA for age but who were wearing glasses for refractive error. Since most children with residual amblyopia wear glasses, we thought it would be helpful to know whether the impact of residual amblyopia is different from the impact of glasses wear itself. All glasses controls had no eye disease other than refractive error, no previous eye treatment other than glasses, and no history of other eye problems. Fifteen of these glasses controls were reported in a previous study.
All children completed the Child PedEyeQ and the Child PedsQL and 1 parent or legal guardian for each child completed the Proxy PedEyeQ, Parent PedEyeQ, Proxy PedsQL, and the PedsQL Family Impact module. The majority of children/parents completing questionnaires did so electronically on an iPad; others completed on paper.
Pediatric Eye Questionnaire
The PedEyeQ , comprises Child, Proxy, and Parent components, each with distinct, separately scored domains, using a 3-point frequency scale for responses (“Never,” “Sometimes,” “All of the time”). The Child 5-11 PedEyeQ (used in the present study) consists of Functional vision, Bothered by eyes/vision, Social, and Frustration/worry domains. The Proxy 5-11 PedEyeQ consists of 5 domains: Functional vision, Bothered by eyes/vision, Social, Frustration/worry, and Eye care ; and the Parent PedEyeQ assesses the effect of the child’s eye condition on the parent and family in 4 domains: Impact on parent and family, Worry about child’s eye condition, Worry about child’s self-perception and interactions, and Worry about child’s functional vision. (Full questionnaires in English and Spanish, with Rasch-scoring look-up tables, are freely available at public.jaeb.org/pedig/view/Other_Forms .)
Pediatric Quality of Life Inventory
The PedsQL is a general HRQOL questionnaire. For the present study we used the Child module (5-7- and 8-12-year-old versions), each with 23 items in 4 domains (physical, emotional, social, and school functioning), the Proxy module (parallel to Child), and the Family Impact PedsQL module (8 domains). , PedsQL questionnaires use 5 response options with the exception of the Child 5-7, which uses 3 options, and the respondent is instructed to respond based on their experience over the past month ( www.pedsql.org/about_pedsql.html ; full questionnaires available by purchase only).
Rasch-calibrated PedEyeQ domain scores were calculated for each participant, using previously published Rasch look-up tables (freely available at public.jaeb.org/pedig/view/Other_Forms ), and converted to 0 (worst) to 100 for interpretation. All VA data were converted to logMAR for analysis, calculating a logMAR letter score (Snellen equivalent reported for ease of interpretation). Median and range of VA and refractive error were calculated for amblyopic and fellow eyes for children with residual amblyopia and right eyes for normal controls and glasses controls.
The primary analysis was a comparison of median PedEyeQ domain scores and PedsQL domain scores between children with residual amblyopia and visually normal controls not wearing glasses. In secondary analyses, we compared PedEyeQ domain scores and PedsQL domain scores in children with residual amblyopia and visually normal controls wearing glasses. Pairwise Wilcoxon tests were used for all analyses. Mean differences with a 95% confidence interval (CI) around the mean difference were also calculated.
Demographics and clinical characteristics for all enrolled children and parents are shown in Table 1 . Median amblyopic-eye VA was 20/50 (range 20/32 to 20/320) ( Table 1 ). No children had developmental delay.
Residual Amblyopia vs Visually Normal Controls (Not Wearing Glasses)
Children with residual amblyopia had lower (worse) scores than visually normal controls not wearing glasses, on each of the 4 Child PedEyeQ domains ( P ≤ .004 for each; Figure 1 ; Table 2 ). The greatest difference was on the Functional vision domain (median 75 vs 95; mean difference −18; 95% CI −29 to −7; P < .001; Figure 1 ; Table 2 ).
|PedEyeQ Domains||Median (Range) PedEyeQ Scores||P Value for Difference, Amblyopia vs Normal||Mean Difference (95% CI), Amblyopia – Normal||P Value for Difference, Amblyopia vs Glasses||Mean Difference (95% CI), Amblyopia – Glasses|
|Residual Amblyopia (N = 17)||Normal Controls Without Glasses (N = 48)||Glasses Controls (N = 19)|
|Child PedEyeQ domains|
|Functional vision||75 (15-95)||95 (45-100)||85 (60-100)||<.001∗||−18 (−29 to −7)||.09||−12 (−23 to 0)|
|Bothered by eyes/vision||80 (35-100)||95 (30-100)||90 (45-100)||.002∗||−13 (−23 to −3)||.15||−6 (−18 to 5)|
|Social||90 (55-100)||100 (60-100)||90 (60-100)||.004∗||−7 (−13 to −2)||.68||−1 (−9 to 7)|
|Frustration/worry||80 (50-100)||100 (35-100)||90 (35-100)||<.001∗||−16 (−23 to −8)||.03∗||−9 (−18 to 1)|
|Proxy PedEyeQ domains|
|Functional vision||65 (35-95)||100 (80-100)||90 (40-100)||<.001∗||−31 (−39 to −24)||.008∗||−15 (−26 to −3)|
|Bothered by eyes/vision||75 (45-100)||100 (80-100)||95 (55-100)||<.001∗||−22 (−30 to −13)||.006∗||−13 (−23 to −2)|
|Social||88 (44-100)||100 (94-100)||94 (56-100)||<.001∗||−23 (−34 to −12)||.049∗||−14 (−26 to −2)|
|Frustration/worry||70 (40-100)||100 (80-100)||100 (40-100)||<.001∗||−25 (−37 to −13)||.050∗||−14 (−29 to 1)|
|Eye care||67 (42-100)||100 (67-100)||100 (50-100)||<.001∗||−28 (−40 to −16)||.06||−16 (−30 to −2)|
|Parent PedEyeQ domains|
|Impact on parent and family||90 (60-100)||100 (85-100)||100 (60-100)||<.001∗||−16 (−23 to −9)||.02∗||−9 (−17 to −1)|
|Worry about child’s eye condition||60 (0-100)||100 (40-100)||80 (35-100)||<.001∗||−34 (−46 to −22)||.01∗||−17 (−31 to −3)|
|Worry about child’s self-perception and interactions||71 (21-100)||100 (64-100)||93 (7-100)||<.001∗||−27 (−38 to −16)||.07||−11 (−26 to 4)|
|Worry about child’s functional vision||62 (6-100)||100 (50-100)||87 (12-100)||<.001∗||−30 (−42 to −18)||.050∗||−13 (−28 to 2)|