# Untreated Amblyopia, Strabismus, Diplopia, and Binocular Vision Disorders

## Scope and evidence standards

This report stays within **orthoptics / pediatric-ophthalmology / strabismus / amblyopia / binocular-vision** evidence and does **not** substitute optometry workforce or practice data for orthoptics. The emphasis is person-level evidence for what untreated conditions cost people over a lifetime, and what treatment measurably restores. Where possible, I prioritized peer-reviewed studies, official guidance, PEDIG/CITT work, and named professional bodies. Because the user asked for “Source (+URL)” for every statistic, the **citation markers in the Source column link directly to the underlying source URL**. Older but still foundational studies are included when newer estimates do not exist; those rows are labeled accordingly. citeturn40search0turn29search3turn22search0turn23search0

## Stat cards

| Value | Metric / what it measures | Scope & population | Period | Source | Confidence | One-line so what |
|---|---|---|---|---|---|---|
| **2.6 (95% CI 1.4–4.5)** | Relative risk of **bilateral visual impairment** in people with amblyopia vs no amblyopia | Rotterdam Study; population-based cohort, adults **55+** in the Netherlands; **n=5,220**, including **192** with amblyopia | Published 2007 | van Leeuwen R, et al. *Br J Ophthalmol* 2007, “Risk of bilateral visual impairment in individuals with amblyopia: the Rotterdam study.” citeturn40search0turn40search1 | [Measured] | Amblyopia is not just “one weak eye”; it materially raises the chance of ending up impaired in **both** eyes later in life. |
| **18% vs 10%** | **Lifetime risk** of bilateral visual impairment, amblyopia vs no amblyopia | Same Rotterdam modeled life-table, adults with vs without amblyopia | Published 2007 | van Leeuwen R, et al. citeturn40search0turn40search1 | [Modeled] | The “double-whammy” risk is the clearest long-horizon argument for treatment: protecting future independence if the better eye is later injured or diseased. |
| **7.2 vs 6.7 years** | Expected years lived with bilateral visual impairment, amblyopia vs no amblyopia | Same Rotterdam study | Published 2007 | van Leeuwen R, et al. citeturn40search0turn40search1 | [Modeled] | The issue is not only whether bilateral impairment happens, but how long a person may live with it. |
| **At least 1.2% (95% CI 1.1–1.4)** | Projected lifetime risk of serious vision loss in the **better-seeing eye** of a person with amblyopia | UK population-based study of incident visual impairment after loss of the non-amblyopic eye | Published 2002 | Rahi JS, et al. *Lancet* 2002 / PubMed abstract, “Risk, causes, and outcomes of visual impairment after loss of vision in the non-amblyopic eye.” citeturn33search2 | [Estimate] | Even if the amblyopic eye stays weak for life, treatment still matters because it reduces the consequences if the “good” eye is lost later. |
| **32% vs 14%; adjusted OR 2.79 (95% CI 2.48–3.13)** | Anxiety prevalence and odds in adults with strabismus vs matched adults without strabismus | NIH All of Us, diverse US adult cohort | Published 2024 | Jin K, et al. *JAMA Ophthalmology* 2024 / Harvard summary of study. citeturn29search3turn29search5 | [Measured] | Untreated strabismus is associated with a large mental-health burden in real-world adults, not just in small clinic samples. |
| **33% vs 14%; adjusted OR 2.95 (95% CI 2.63–3.31)** | Depression prevalence and odds in adults with strabismus vs controls | Same All of Us US adult cohort | Published 2024 | Jin K, et al. citeturn29search3turn29search5 | [Measured] | Depression risk is roughly tripled in this cohort, reinforcing that ocular misalignment is not “cosmetic only.” |
| **3% vs 1%; adjusted OR 2.92 (95% CI 1.99–4.27)** | Schizophrenia-spectrum disorder odds in adults with strabismus vs controls | Same All of Us cohort | Published 2024 | Jin K, et al. citeturn29search3turn29search5 | [Measured] | The psychosocial burden extends beyond low self-esteem into clinically coded mental-health conditions. |
| **19.04% vs 2.12%** | Social phobia diagnosis in children with strabismus vs controls | Case-control study; **42 strabismic children** vs matched controls | Published 2011 | Cumurcu T, et al. *Can J Ophthalmol* / PubMed abstract. citeturn8search9 | [Measured] | In children, the psychosocial hit is already visible at diagnosable-anxiety level, not only as vague “confidence” concerns. |
| **53.1%** | Social phobia rate among adults with strabismus | Adult case-control study | Published 2009 | Bez Y, et al. *J AAPOS* / PubMed and PDF snippet. citeturn8search0turn8search4 | [Measured] | Single-study, but striking: many untreated adults with visible strabismus report clinically relevant social fear. |
| **Weighted OR 1.92 (95% CI 1.38–2.66)** | Pooled association between childhood/adolescent strabismus and mental-health disorders | Meta-analysis, **683,942** participants across studies published 2008–2024 | Published 2025 | Krungkraipetch L, et al. *Ophthalmology and Therapy* 2025. citeturn36search4turn36search5 | [Estimate] | Across studies, strabismus is associated with roughly **double** the odds of later mental-health disorders in youth. |
| **Children with esotropia/exotropia rated more negatively on all 10 characteristics; esotropia worse on 4/10** | Social-perception bias by teachers toward children with strabismus | Teacher-photo questionnaire study | Published 2003 | Uretmen O, et al. *Acta Ophthalmologica* / PubMed abstract. citeturn31search0turn31search2 | [Measured] | The stigma starts early and is visible in adult judgments of children, which has obvious downstream implications for school life. |
| **Respondents age ≥6 invited children with a squint to birthday parties significantly less often** | Peer social exclusion | Experimental photo-based child/adult perception study | Published 2011 | Mojon-Azzi SM, et al. *Br J Ophthalmol* / PubMed. citeturn11search0 | [Measured] | Social exclusion appears by early grade-school age, which helps explain later self-esteem and anxiety effects. |
| **Women with normal alignment had higher hiring-preference scores than strabismic women (P=0.007); no significant male difference (P=0.47)** | Simulated employability penalty from visible large-angle horizontal strabismus | Experimental hiring study using application materials/photos | Published 2000 | Coats DK, et al. *Ophthalmology* abstract/snippet. citeturn10search0turn10search2 | [Measured] | Visible strabismus can change hiring judgments, especially for women, in controlled applicant simulations. |
| **47%** | Share of Swiss headhunters saying strabismic applicants have more difficulty obtaining a job | Telephone survey of **20** headhunters | Published 2007 | Mojon-Azzi SM, Mojon DS. *Ophthalmologica*. citeturn10search6turn9view2 | [Low-confidence] | Small judgment study, but it points in the same direction as experimental hiring work: employability is affected. |
| **72.5%** | Share of headhunters saying strabismic individuals would have more difficulty finding a job | Swiss headhunter survey | Published 2009 | Mojon-Azzi SM, Mojon DS. *Ophthalmic and Physiological Optics*. citeturn10search9turn10search11 | [Low-confidence] | Different survey, same pattern: visible eye misalignment is perceived as a labor-market disadvantage. |
| **Strabismic subjects perceived as less attractive, less intelligent, and less likeable; p<0.001 for attractiveness and erotic appeal** | Social-perception / dating penalty | Dating-agent perception study | Published 2008 | Mojon-Azzi SM, et al. *Br J Ophthalmol* snippet. citeturn30search2turn30search5 | [Low-confidence] | Romantic and social appraisal penalties are measurable, not anecdotal. |
| **73% vs 43% vs 33% vs 35%** | “Successful or improved” outcome after 12 weeks of CI treatment | Children **9–17** with symptomatic convergence insufficiency; office-based vergence/accommodative therapy vs pencil push-ups vs home computer therapy+PP vs office placebo | Published 2008 | CITT Study Group, randomized clinical trial. citeturn13search0turn13search2turn13search3 | [Measured] | Orthoptic-style office-based therapy improves CI signs/symptoms much more reliably than common home or placebo regimens. |
| **Mean CISS 15.1 vs 21.3 vs 24.7 vs 21.9** | Symptom burden after 12 weeks of CI treatment | Same CITT pediatric RCT | Published 2008 | CITT Study Group. citeturn13search2 | [Measured] | Treatment meaningfully reduces reading/near-work symptoms even when broader academic outcomes are harder to move. |
| **75–80% vs ~30%** | Proportion reaching normal range for clinical CI signs after office therapy vs placebo | CITT-ART, children **9–14** with symptomatic CI | Published 2019 | NIH/NEI release summarizing CITT-ART secondary outcomes. citeturn12search5turn12search16 | [Measured] | Treatment clearly restores vergence/accommodative function. |
| **No better than placebo for reading improvement** | Reading outcome after CI treatment | CITT-ART randomized trial, children **9–14** | Published 2019 | CITT-ART / NEI and PubMed abstract. citeturn12search1turn12search5 | [Measured] | Important nuance: fixing symptomatic CI improves eye teaming, but the best RCT did **not** show a reading-comprehension advantage over placebo. |
| **ABS 15.6 vs 11.7 vs 8.7** | Academic Behavior Survey score: CI+parent-reported ADHD vs CI without ADHD vs normal binocular vision | Children **9–17** | Published 2009 | Rouse M, et al. *Optom Vis Sci* / abstract and PMC snippet. citeturn17search0turn17search2turn17search3 | [Measured] | Symptomatic CI is associated with more parent-observed schoolwork/attention problems even without parent-reported ADHD. |
| **ABS change: −4.0 vs −2.9 vs −1.3 points** | Improvement in adverse academic behaviors after CI treatment among successful / improved / non-responder groups | Children **9–17** after 12-week treatment | Published 2012 | Borsting E, et al. *Optom Vis Sci*. citeturn16search0turn16search3 | [Measured] | When CI treatment works clinically, parents also report less avoidance, inattention, and schoolwork difficulty. |
| **Poor school readiness association, but no later adverse cognitive-performance trajectory** | School-readiness / cognition finding in amblyopia + strabismus | Population cohort | Published 2020 | Gitsels LA, et al. *PLOS One*. citeturn18search0turn18search8 | [Measured] | Early developmental friction is plausible, but evidence that amblyopia alone worsens later academic attainment is weak. |
| **No association with adverse core-subject performance trajectories** | Longitudinal school attainment after amblyopia | UK Millennium Cohort population study | Published 2023 | Horvat-Gitsels LA, et al. *PLOS One*. citeturn18search1turn18search3 | [Measured] | Broad educational attainment is not consistently worse in treated amblyopia cohorts; this is a place where the evidence is more reassuring than often assumed. |
| **Utility 0.85 ± 0.20 to 0.96 ± 0.11; mean QALY gain 2.61; cost-utility \$1,632/QALY** | Health-state utility gain and cost per QALY from adult strabismus surgery | US adult strabismus surgery cost-utility analysis | Published 2006 | Beauchamp CL, et al. *J AAPOS* / PubMed abstract. citeturn20search2turn19search0 | [Estimate] | On standard cost-utility grounds, adult strabismus surgery looks highly cost-effective, which undercuts the “cosmetic-only” argument. |
| **\$2,281/QALY gained; sensitivity range \$2,053–\$2,509/QALY** | Cost-utility of amblyopia therapy vs no treatment | US cost-utility analysis | Published 2002 | Membreno JH, et al. *J Pediatr Ophthalmol Strabismus* / PubMed abstract. citeturn21search12 | [Estimate] | Even older economic models suggest amblyopia treatment buys lifelong value at low cost per QALY. |
| **€2,369/QALY** | Incremental cost-effectiveness ratio of amblyopia treatment | German probabilistic Markov model | Published 2004 | König HH, et al. *Br J Ophthalmol* / PMC/PubMed abstract. citeturn21search0turn21search2turn19search12 | [Modeled] | A second model, in another health system, points the same way: amblyopia treatment is likely cost-effective. |
| **20/40 with both eyes together, and 20/40 in one eye with at least 20/70 in the other** | California DMV screening standard for driver licensing | California noncommercial driver licensing | Current CA DMV page, accessed 2026 | California DMV official guidance. citeturn23search0 | [Measured] | Loss of the better eye, or new diplopia/field loss, can directly threaten practical independence like driving. |
| **If not correctable to 20/40 in each eye, or possible field loss, full visual-field exam required** | California DMV escalation threshold for visual-field evaluation | California driver medical review process | DL 62 form current online in 2026 | California DMV DL-62 official form. citeturn23search10 | [Measured] | Binocular disorders become a licensing issue once acuity or fields are insufficient, which is why preserving binocular function matters. |
| **Stable uncorrected diplopia must usually be adapted to for 6 months or more; patching not acceptable; insuperable diplopia permanently refused** | Official diplopia standard for private driving | UK DVLA Group 1 licensing guidance | Current official guidance, accessed 2026 | UK DVLA official guidance. citeturn22search0 | [Measured] | Persistent double vision can directly disqualify driving unless the condition is demonstrably adapted and stable. |
| **Typical US visual-field requirements ~110°–140°** | Range of visual-field requirements for driver licensing | US state licensing standards review | Review published 2010 | Bron AM, et al. review of international driver-licensing vision requirements. citeturn22search1turn22search6turn22search9 | [Estimate] | Even when acuity is adequate, binocular field loss can threaten licensure. |
| **Binocular vision not a prerequisite for flying, but depth perception via stereopsis or monocular cues is necessary** | Occupational relevance of stereopsis / binocular function | FAA aeromedical guidance | FAA guide online, accessed 2026 | FAA Guide for Aviation Medical Examiners. citeturn22search2 | [Measured] | Some jobs can be adapted with monocular cues, but binocular function still matters for performance and certification pathways. |
| **Adjusted OR about 1.27 for injury/fall/fracture overall; diplopia OR 1.36** | Injury/fall/fracture risk associated with disorders of binocular vision in older adults | Medicare beneficiaries **≥65**, **n=2,196,881** over a 10-year period | Published 2015 | Pineles SL, et al. *JAMA Ophthalmology* / abstract snippets. citeturn25search2turn25search3turn26search9 | [Measured] | In older adults, untreated binocular disorders are not just bothersome; they are linked to concrete mobility and injury risk. |
| **Severe binocular visual-field loss OR 1.50 (95% CI 1.11–2.02)** | Prospective risk of frequent falls | Community-dwelling older white women, **n=4,071** | Published in cohort study summarized in abstract | Study of Osteoporotic Fractures abstract snippet. citeturn25search10 | [Measured] | Field loss has real downstream safety costs, which is part of the independence argument for preserving binocular function. |
| **Psychosocial score exceeded agreement limits in 48% at 1 year vs 30% at 6 weeks; function 67% vs 51%** | Durable HRQOL improvement after successful adult strabismus surgery | Adult postoperative cohort | Published 2012 | Hatt SR, et al. *Am J Ophthalmol*. citeturn37search14 | [Measured] | Benefits after successful alignment are not just immediate; quality-of-life gains can deepen over time. |
| **Overall IXTQ domain improvement 10.7 to 34.5 points; resolved-surgery cases improved 19.8 to 46.0 points** | Child/parent-reported HRQOL improvement after intermittent exotropia surgery | Children **3–11** followed to 36 months after surgery | Published 2021 | Holmes JM, et al. *J AAPOS* / PMC and institutional summaries. citeturn32search0turn32search2turn32search3 | [Measured] | Validated child/parent PROMs show that surgery restores quality of life, especially when alignment outcomes are good. |
| **Postoperative strabismus-related QoL higher; anxiety and depression lower** | Psychosocial change after strabismus surgery | Pre/post cohort, **59 patients** | Published 2023 | Ehlers M, et al. *BMJ Open Ophthalmology*. citeturn37search0turn37search6turn38search7 | [Measured] | Modern routine-clinic PROM data support the older literature: treatment can improve mental well-being as well as alignment. |
| **AS-20 has 20 items across psychosocial and function domains** | Validated adult strabismus PROM structure | Adults with strabismus | Original 2009 development; later Rasch evaluation 2012 | Hatt SR, et al. 2009; Leske DA, et al. 2012. citeturn28search14turn27search9turn27search19 | [Measured] | This is the main validated adult PROM used to quantify “this affects my life” in a reproducible way. |
| **A&SQ validated; “fear of losing the better eye” correlated significantly with utility** | Disease-specific QoL domain in amblyopia/strabismus | Adults with amblyopia and/or strabismus | Published 2009–2010 | van de Graaf ES, et al. *Construct validation* and utility-analysis reports. citeturn27search1turn20search6 | [Measured] | The better-eye threat is not just an analyst’s construct; patients report it as a distinct QoL burden. |
| **Review identified 71 PROMs, 32 disease-specific, but only 4 had sufficient evidence to recommend use** | State of PROM measurement in amblyopia/strabismus | Systematic review of instruments | Published 2018 | Kumaran SE, et al. systematic review. citeturn28search0turn27search21turn27search8 | [Estimate] | PROM evidence exists, but the measurement ecosystem is still thinner than for many other ophthalmic conditions. |

## Narrative synthesis

The cleanest high-confidence finding is the **lifetime independence argument** for amblyopia treatment. In the Rotterdam Study, amblyopia was associated with a **2.6-fold** higher risk of bilateral visual impairment, and the modeled lifetime risk of bilateral impairment was **18%** in amblyopic individuals versus **10%** in those without amblyopia. The older UK surveillance work estimated the lifetime risk of serious vision loss in the better-seeing eye of someone with amblyopia at **at least 1.2%**. Put plainly: therapy is not only about making the weaker eye better *today*; it is also about reducing the consequences if the “good” eye is ever damaged by trauma, retinal disease, cataract, or other pathology decades later. That is why amblyopia management can reasonably be framed as **protection of future autonomy** rather than a narrow childhood vision project. citeturn40search0turn40search1turn33search2

For strabismus, the evidence is strongest that untreated visible misalignment has **real psychosocial and social-function costs**. In a large and diverse US adult cohort, strabismus was associated with markedly higher odds of anxiety, depression, bipolar disorder, schizophrenia-spectrum disorder, and substance-related diagnoses, with adjusted odds ratios generally around **2 to 3**. Smaller case-control and experimental studies point the same way: diagnosable social phobia is more common in both children and adults with strabismus, teachers rate affected children more negatively, peers are less accepting, and simulated hiring judgments penalize visible deviation. These are not perfect causal studies, and some are older or perception-based rather than real labor-market follow-up. Still, the pattern is unusually consistent across methods: **misalignment changes how other people respond to you**, and those social responses show up in validated mental-health and quality-of-life measures. citeturn29search3turn29search5turn8search9turn8search4turn31search0turn10search0turn10search9turn36search5

Treatment does restore more than cosmesis. For adults with strabismus, validated PROMs show durable gains in psychosocial and functional quality of life after successful surgery, and modern pre/post data also show lower postoperative anxiety and depression. In children with intermittent exotropia, the IXTQ demonstrates sizable improvements in child- and parent-reported quality of life up to **36 months** after surgery, especially when alignment outcomes are good. Economic studies, though older and model-dependent, also converge on the same judgment: adult strabismus surgery and childhood amblyopia therapy are **highly cost-effective** by usual QALY thresholds. The practical implication is that treatment is not well-described as “cosmetic”; it restores day-to-day function, perceived social normalcy, and probable lifetime value. citeturn37search14turn37search6turn32search0turn32search3turn20search2turn21search12turn19search12

The school/reading picture needs more nuance. Symptomatic convergence insufficiency clearly causes near-work symptoms and parent-observed academic-behavior problems, and office-based vergence/accommodative therapy improves clinical signs much more than placebo or weaker home regimens. But the best large randomized trial, CITT-ART, did **not** show an added reading-comprehension benefit over placebo despite better convergence outcomes. So the defensible synthesis is: **CI treatment restores binocular function and reduces symptom burden**, and that may make schoolwork more tolerable, but evidence that treatment directly lifts standardized reading performance is not yet strong. Likewise, recent cohort studies do **not** show consistent long-term academic underachievement from amblyopia alone, even though early school-readiness friction may exist when amblyopia co-occurs with strabismus. citeturn13search2turn12search5turn17search3turn16search3turn18search0turn18search1

The independence stakes extend beyond mood and school. Official licensing standards show that persistent diplopia and visual-field loss can directly threaten **driving eligibility**, while Medicare and cohort data link binocular-vision disorders and field loss to **falls, fractures, and injuries** in older adults. Diplopia in particular had the strongest injury association in the large Medicare analysis. This matters because orthoptic disorders are often dismissed when visual acuity looks “good enough.” In real life, acuity is only part of function. Fusion, stereopsis, field, and freedom from diplopia are what make reading, mobility, driving, and many work tasks efficient and safe. citeturn22search0turn23search0turn25search3turn25search10turn22search2

## Validated patient-reported outcomes

The most useful validated PROMs in this space are the **Adult Strabismus-20 (AS-20)** for adults with strabismus, the **Intermittent Exotropia Questionnaire (IXTQ)** for children with intermittent exotropia and their parents, and the **Amblyopia and Strabismus Questionnaire (A&SQ)** for amblyopia/strabismus-related quality of life. A 2018 systematic review found **71 PROMs** overall and **32 disease-specific** instruments, but only a small subset had enough psychometric support to recommend routine use. In other words, the field has real measurement tools, but not an abundance of excellent ones. citeturn28search0turn27search21turn27search8

What these instruments show is consistent with the broader literature. The **AS-20** captures both psychosocial and functional burden in adults and is responsive to postoperative improvement. The **IXTQ** shows that successful childhood exotropia surgery improves not just parent concern but the child’s own reported quality of life. The **A&SQ** is especially useful for surfacing a dimension that clinicians sometimes understate: **fear of losing the better eye**. That domain’s correlation with utility estimates is one of the clearest reminders that the stakes of amblyopia are not fully captured by measuring the amblyopic eye alone. citeturn28search14turn27search9turn32search0turn32search3turn27search1turn20search6

## Data gaps

The evidence leaves some important questions only partly answered.

- **Contemporary fellow-eye risk in amblyopia** is still mostly inferred from older European cohort/surveillance work. There is no modern US registry-quality estimate I found that cleanly updates the lifetime “double-whammy” risk. citeturn40search0turn33search2
- **Real-world employability and earnings effects** of visible strabismus are poorly measured. Existing studies are mostly perception, survey, or simulation studies rather than longitudinal labor-market data. citeturn10search0turn10search9turn10search6
- **Academic outcomes** are mixed: symptomatic CI clearly affects near-work symptoms and parent-observed school behaviors, but the strongest RCT did not show improved reading over placebo, and population data for amblyopia alone are relatively reassuring. That leaves a gap between symptom relief and hard educational outcomes. citeturn12search5turn16search3turn18search1
- **Driving and crash risk specifically in diplopia/strabismus** is thinner than licensing-standard literature. We have standards and injury/falls associations, but less direct modern crash-risk evidence. citeturn22search0turn25search3
- **Utility weights and QALY models** for amblyopia and strabismus are informative but mostly older; newer cost-effectiveness work is relatively sparse, and estimates are sensitive to assumptions about utility loss from unilateral vision impairment. citeturn20search2turn21search12turn19search12turn19search1
- **Orthoptics-specific, clinic-to-life outcomes** are still underdeveloped. The literature is much stronger on diagnosis, alignment, and visual function than on long-term participation outcomes such as employment retention, driving continuity, independent living, or caregiver burden. citeturn28search12turn27search21