FormalPara Key Summary Points

Why carry out this study?

While there is a plethora of evidence reporting the psychosocial impacts of traditional treatments for amblyopia, such as patching, less is known about the impacts of amblyopia alone on health-related quality of life (HRQoL).

This knowledge is critical to enhance treatment compliance, and therefore the present study sought to address this gap by exploring the patient experience of amblyopia on HRQoL domains.

What was learned from the study?

The study findings make an important contribution to the literature by providing valuable qualitative insights into the adult and pediatric experiences of amblyopia from a multi-stakeholder perspective. The findings supported the development of a disease model providing a comprehensive depiction of the experience of amblyopia and its treatments.

Understanding the substantial and multifaceted impacts of amblyopia will help support patient–clinician interactions in clinical practice when managing amblyopia and prescribing treatment. These findings have also supported the development of new outcome measures for use in amblyopia clinical trials.

Introduction

Amblyopia is a neurodevelopmental vision disorder, clinically defined by a unilateral or bilateral decrease in visual acuity (VA) that cannot be attributed to structural abnormalities of the eye [1], resulting in poor vision outcomes for patients. Principle causes of amblyopia are differences in refractive error between the eyes (anisometropia), ocular misalignment resulting in disrupted binocular interaction (strabismus), or stimulus deprivation (e.g., cataract) [2]. The global prevalence in children is estimated at 1.36% and amblyopia is a leading cause of vision loss in children [3, 4]. In addition to reduced VA, visual functions including depth perception (stereopsis), and peripheral vision can be affected [2, 5], resulting in impacts on mobility, conducting activities of daily living (ADL), and on broader domains of health-related quality of life (HRQoL) including work/school, emotional, and social functioning [5, 6].

The potential for successful treatment of amblyopia to ameliorate vision loss reduces with age, and if left untreated or incompletely treated in early childhood, it can cause lifelong visual impairment [7]. Traditional treatments promote the visual experience of the amblyopic eye via patching and atropine penalization of the fellow eye [8]. While penalization therapies improve visual function [9], they significantly impact HRQoL. In particular, patching is stigmatizing, with children more likely to experience bullying and report feelings of embarrassment, self-consciousness, and shame [8, 10]. Patching can also disrupt schooling, interfere with social activities, and cause physical discomfort [11]. Consequently, poor compliance and early cessation of treatment can occur, resulting in poor clinical outcomes [10].

More recently, novel binocular amblyopia treatment approaches have emerged, based on evidence that amblyopia patients can combine information between their eyes if suppression is reduced through contrast balancing [12, 13]. With these treatments, full contrast images are presented to the amblyopic eye while reduced contrast images are presented to the fellow eye, often in the form of a dichoptic movie or video game [12,13,14]. The difference in contrast of images presented to the amblyopic and fellow eyes is gradually balanced as treatment progresses, with the aim of promoting binocular fusion. These novel binocular approaches may mitigate some of the traditional treatment impacts by removing the physical and/or visible aspects that can lead to stigmatization, discomfort, and impaired social and physical functioning that is associated with patching [6, 15].

While there is a plethora of evidence reporting the psychosocial impacts of traditional treatments in children [10, 11] and the impact of cosmetically obvious strabismus, less is known about the impacts of amblyopia alone on HRQoL. Although experimental studies indicate a functional impact of amblyopia, qualitative exploration of impacts recognized by patients is limited [5]. Furthermore, lack of knowledge about the condition and treatment has been identified as a key barrier to treatment uptake [8], suggesting that understanding the symptoms and impacts of amblyopia, as well as the impacts of not undertaking treatment, is vital to enhance treatment compliance. Therefore, the overall objective of this study was to explore the experience of amblyopia, including symptoms, functional impairment, wider HRQoL impacts, and treatment experience, in adult and pediatric populations from a multi-stakeholder perspective to inform the development of a disease model depicting the patient experience.

Methods

Study Design

This qualitative study comprised two key stages to inform the development of a disease model depicting the patient experience of amblyopia: (1) a targeted qualitative literature review; (2) combined concept elicitation (CE) and cognitive debriefing (CD) interviews with individuals and caregivers of children with amblyopia, and ophthalmologists experienced in treating amblyopia from the United States (US), France, and Germany. To ensure clinical insight into the interpretation of the study findings, three additional clinical experts in amblyopia (from the UK, US, and Australia) provided input at key stages. Figure 1 provides an overview of the study design. Note: given that this article focuses on the patient experience of amblyopia, only the CE interview findings are described; the CD interview findings will be discussed elsewhere [16]. The study was approved and overseen by Western Copernicus Group Independent Review Board (WCG IRB, reference: 20204313) in the US. Written informed consent and/or assent was obtained prior to conduct of any study-related activities. The study was performed in accordance with the Helsinki Declaration of 1964, and its later amendments.

Fig. 1
figure 1

Overview of study design

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Targeted Qualitative Literature Review

To gain an initial understanding of the patient experience of amblyopia, a targeted review of published qualitative literature was conducted. Searches were conducted in June 2020 via computerized bibliographic databases, including PubMed (MEDLINE), Embase, and PsycINFO, using a combination of keywords and Medical Subject Headings (MeSH) relating to the disease (e.g., amblyopia, lazy eye) and qualitative research (e.g., interview, focus groups). Supplementary searches of Google Scholar and key ophthalmology and health outcome conference proceedings (2019–2020) were performed to ensure all recent publications were identified. Abstracts identified were screened for eligibility and full-text review. Eligible abstracts had to present qualitative data specific to, or including, amblyopia patients, concerning symptoms and/or impacts of amblyopia. Eligible abstracts were graded according to the extent to which they met the study objectives. Abstracts focusing on amblyopia and explicitly referencing data on symptoms, impacts, and/or treatment concepts were considered most relevant and were prioritized for full-text review (grade 1). Following this, abstracts focusing on amblyopia that alluded to data on symptoms, impacts, and/or treatment concepts or presented qualitative data exploring themes that may/may not be relevant (grade 2), or abstracts focusing on patients with vision impairment that offered limited data specific to amblyopia patients (grade 3), were considered for inclusion. Previously conducted social media listening (SML) studies exploring the patient experience of amblyopia in adults and children were reviewed alongside the selected publications to provide further insight [17].

Full-text articles and the SML studies were reviewed using inductive thematic analysis [18], allowing themes to be explored freely rather than searching for themes based on pre-existing theory. Atlas.ti (version 8) [19] qualitative analysis software was used to assign codes for each concept and sub-concept reported in the articles. The coded data were extracted into Excel to support further analysis and data filtering. The literature review findings informed the interview guide used in the qualitative interviews.

Qualitative Interviews

Sample

A sample of 192 participants from the US (n = 96), France (n = 48), and Germany (n = 48) was targeted for the patient/caregiver interviews. The target sample size was double in the US given that the US has a larger overall population. Participants comprised adults (aged ≥ 18), adolescents (aged 13–17), older children (aged 9–12), and younger children (aged 4–8) with amblyopia and their caregivers. Based on current guidance, children aged 4–8 were interviewed together with their caregiver as a “dyad,” as self-report is often unreliable in younger children. Given that reliability improves with age, children aged 9–12 were interviewed separately from their caregiver to ensure that the child could discuss their experiences without their caregiver’s influence [20]. Therefore, the study aimed to conduct 160 interviews.

The sample size was determined based on the principles of concept saturation: the point at which no new concepts are likely to emerge with further interviews [21]. Based on previous research, a target of 160 interviews with at least 24 interviews in each age group was expected to be sufficient for achieving concept saturation across the total sample [22]. Ten eyecare clinicians with experience in treating amblyopia from the US, France, and Germany were targeted for the clinician interviews.

Recruitment

Participants were identified by recruitment agencies via optometrist/ophthalmologist referrals, social media advertising, and sharing study invitations with members of patient databases. Patients had to be ≥ 4 years with a clinician-confirmed diagnosis of amblyopia due to strabismus, anisometropia, deprivation, isometropia, or combined mechanism. Caregivers had to be ≥ 18 years and a parent/caregiver of a child aged 4–12 with clinician-confirmed amblyopia (eligibility criteria are detailed in Table 1). A quota sampling approach was employed to ensure a range of key demographic and clinical characteristics (e.g., race, amblyopia type, and severity). Clinicians were also recruited via recruitment agencies and were required to be experienced in treating amblyopia patients. All participants were compensated for their participation.

Table 1 Patient/caregiver eligibility criteria for qualitative interviews
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Procedure

The study was approved and overseen by an independent review board in the US (reference: 20204313). Written informed consent and/or assent was obtained prior to conducting any study-related activities. All interviews were 60 min and conducted via telephone in the participant’s native language by trained qualitative interviewers. A semi-structured interview guide, informed by the literature review findings, guided the discussion. The CE section of the combined CE and CD patient/caregiver interviews lasted approximately 30 min. For the dyad interviews, interviewers were encouraged to engage with the child primarily at the beginning of the interview; the remainder of the interview was conducted with the caregiver alone. Similarly, the CE section of the clinician interviews lasted approximately 30 min.

The CE part of the interviews used broad, open-ended questions to facilitate spontaneous and unbiased elicitation of concepts regarding the patient experience of amblyopia, including symptoms, impacts on HRQoL, and treatment. Focused questions were used if concepts of interest had not emerged or been fully explored. Example questions used in the adult/adolescent interviews are provided in Table 2. To engage the children, creative exercises were utilized, including asking the children to do a drawing that represented their amblyopia and asking them to explain the worst thing about having amblyopia (for children aged 9–12) and choosing images of activities they found difficult to do because of their amblyopia, such as reading and playing ball games (for children aged 4–8). The value of these exercises is primarily in terms of putting the children at ease and perhaps eliciting content that might not emerge from more formal questioning [23]. Importantly, timing of symptoms and HRQoL impacts were explored to determine whether the symptom/impact was indeed due to amblyopia or an underlying comorbid eye condition (e.g., where relevant, was the symptom/impact experienced with or without glasses/lenses) or a side effect of patching (i.e., was the symptom/impact experienced when using both eyes or only when patching).

Table 2 Example questions used in adult/adolescent interviews
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Qualitative Analysis

All interviews were audio-recorded and transcribed verbatim; French and German interviews were further translated into English. The CE section of the transcripts (including the creative exercises) were subjected to thematic analysis using Atlas.ti (Version 8) [19]. Participant quotes pertaining to the study objectives were assigned corresponding concept codes in accordance with an agreed coding scheme. Codes were applied both deductively (based on prior knowledge) and inductively (as emerging from the data). The CE and literature review findings were used to develop a disease model of amblyopia.

Concept saturation analysis was conducted for the patient and caregiver interviews to ensure data collection was exhaustive. Transcripts were chronologically grouped into equal sets and spontaneously reported concepts emerging from each set iteratively compared. Saturation was deemed achieved when no new concepts emerged in the final set of interviews.

Results

Literature Review: Data Sources

The bibliographic database search returned a total of 441 abstracts; 44 met the eligibility criteria and were graded (n = 9 grade 1, n = 11 grade 2, and n = 24 grade 3). Twelve data sources were selected for full-text review [5, 10, 11, 24,25,26,27,28,29], including the nine abstracts deemed most relevant (i.e., assigned a grade 1) from the database search. Most of these publications (n = 8) were journal articles, and one was a doctoral thesis. One grade 1 abstract was not relevant for inclusion following review as the article did not include any qualitative findings; this was replaced by the most relevant grade 2 abstract. Findings from three SML slide deck reports were also reviewed; two in pediatric populations, and one in adults. One child SML study focused on the US and one focused on other geographies (Switzerland, Italy, Australia, India, Canada, Germany, France, UK, Spain, Brazil, and Japan) [17]. The adult SML study was predominantly focused on the US, with some representation of the UK, Canada, Australia, France, and Germany [17]. The key findings within these data sources informed the interview guides.

Qualitative Interviews: Sample Characteristics

Patient and Caregiver Characteristics

Overall, 133 participants were interviewed from the US (n = 77, 57.9%), France (n = 30, 22.6%), and Germany (n = 26, 19.5%); 86 (64.7%) were patients and 47 (35.3%) were caregivers of children aged 4–12. Children aged 4–8 and their caregivers were interviewed together, resulting in a total of 112 interviews conducted. Patient demographic and clinical characteristics were relatively diverse and are summarized in Table 3. Caregiver age ranged from 25 to 52 years (mean 40 years), and most were the child’s mother (n = 39/47, 83.0%).

Table 3 Patient demographic and clinical characteristics
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Clinician Characteristics

Ten ophthalmologists were interviewed from the US (n = 4), France (n = 3), and Germany (n = 3). Ophthalmologist demographic characteristics are summarized in Table 4.

Table 4 Ophthalmologist demographic characteristics
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Summary of Qualitative Research Findings

The literature review and qualitative interview findings informed the development of a disease model of amblyopia (Fig. 2).

Fig. 2
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Disease model of amblyopia. HRQoL health-related quality of life

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Symptoms

Fifteen distinct visual function symptoms were reported during the interviews, nine of which were also reported in the literature review. Reduced VA (blurred vision), impaired depth perception, impaired peripheral vision, and double vision were most frequently reported across all data sources (see Table 5 for example quotes). Over half of participants who were asked suggested that blurred vision was the most bothersome (n = 34/67; 50.7%) and most important to treat (n = 36/63; 57.1%), and n = 7/9 ophthalmologists suggested that VA was most important to measure in a clinical trial context. Similar proportions of each age group reported experiencing each symptom during the interviews. However, symptoms were not explored with children aged 4–8 and their caregivers as they were likely to lack awareness of the symptoms and lack the vocabulary to report them.

Table 5 Overview of visual function symptoms most frequently reported in the literature and by patients/caregivers and ophthalmologists during the interviews
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More participants reported experiencing the four most frequently reported visual function symptoms when using both eyes compared with only when their good eye was covered, indicating that these symptoms can occur regardless of patching. However, for those who wore glasses/lenses, more participants reported experiencing these symptoms only when not wearing glasses/lenses compared with when wearing them, suggesting that other comorbid conditions may be the cause. Nevertheless, a small number of participants reported experiencing each of these symptoms regardless of vision correction, therefore suggesting that they could be attributed to amblyopia.

Some visual function symptoms also had physical impacts on the eye and/or patient, such as eye strain/pain, eye tiredness, and headaches, which could be considered more “secondary.” Several causal and/or comorbid conditions of amblyopia were also reported. Notably, these were only reported within the SML studies, and each condition was often reported as a symptom, cause, comorbidity, or type of amblyopia. With input from the clinical experts, such conditions were categorized as causal and/or comorbid conditions and were considered separate from the core symptoms, as displayed in Fig. 2.

Impacts

Six HRQoL domains were reported to be impacted by amblyopia, broadly categorized as impacts on vision-dependent activities and broader domains of HRQoL (see Fig. 2 and Table 6 for example quotes). Participants mostly discussed HRQoL impacts spontaneously and the proportion of participants from each age group reporting on the various domains was fairly consistent, except for school and work impacts. Unsurprisingly, school impacts were more frequently discussed by adolescents, caregivers, and children, and work impacts were only reported by adults and one adolescent. There were no other notable differences in the impacts experienced between the different age groups. Interestingly, impacts on cognitive functioning, such as developmental delay and learning difficulties, were reported by ophthalmologists only.

Table 6 Overview of impact domains reported in the literature and by patients/caregivers and ophthalmologists during the interviews
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Amblyopia impacted daily activities, with difficulty reading being the most commonly mentioned impact across all data sources. Patients experienced difficulty reading text in books and text that was small or far away (e.g., signs), which was often associated with blurred vision. Impacts on viewing digital devices including computer screens, the TV, and smartphones were also reported. This impact occurred due to blurry vision and difficulty seeing far away, and often resulted in eye strain, eye tiredness, and headaches. Similarly, some patients reported difficulty playing video games, describing the need to move closer to the screen to see clearly and avoid eye pain/strain and headaches. Patients also experienced difficulty engaging in sports/leisure activities such as playing ball games, swimming, and cycling; such impacts were primarily associated with blurred vision, impaired depth perception, and impaired peripheral vision. Many adult patients reported difficulty driving, particularly due to impaired peripheral vision. Impacts on physical functioning included difficulty catching (e.g., balls when playing sports and small objects such as keys) and difficulty moving around (e.g., frequently bumping into people and objects). Generally, these impacts were associated with the four most frequently reported visual function symptoms.

Amblyopia impacted on emotional well-being whereby patients reported having low self-confidence due to the appearance of the eye and feeling frustrated or sad due to difficulty conducting daily activities. Patients also discussed feeling worried/nervous, particularly in relation to future vision deterioration, and feeling embarrassed about their eye wandering (primarily for those with strabismus). In terms of social functioning, participants reported impacts on taking part in activities with friends (e.g., difficulty playing at the park, playing sports or video games, and going to the cinema), often reporting being excluded by their peers. Participants also reported receiving unwanted attention and being teased/bullied due to their eyes being misaligned/wandering. Social functioning impacts were associated with various symptoms including impaired peripheral vision, double vision, and headaches, among others.

Impacts on work and school were frequently reported in the literature and throughout the interviews. Children and adolescents described difficulties reading the board in class and concentrating due to blurred and double vision. Similarly, adults reported reduced productivity at work due to eye tiredness, blurred vision, and eye strain/pain, often having to take breaks from screens and resting their eyes. Both patients and ophthalmologists reported a limited career choice, with amblyopia patients being unable to pursue careers such as being a pilot, military service, and certain medical professions, due to poor binocular vision.

Treatment Impacts and Barriers to/Facilitators of Treatment Use

The impacts of various amblyopia treatments on HRQoL were also discussed in the literature and the interviews (see Fig. 2 and Table 7 for example quotes). Treatment impacted daily activities with patching causing difficulty reading and using digital devices and glasses causing difficulty participating in sports/leisure activities. Patching also affected patients’ ability to move around, causing them to bump into things, and productivity at school/work with tasks taking longer to complete. Treatment had a profound impact on patients’ emotional well-being and social functioning. Specifically, patching and glasses were associated with low self-esteem and receiving unwanted attention such as staring and comments from peers. Patching also caused physical discomfort/pain and sometimes left marks on the skin, while eye drops sometimes caused burning/discomfort, and all treatments were associated with a financial impact. Such impacts led to poor adherence from children and parental reluctance to use certain treatments. However, getting into a routine of using treatment and noticing an improvement in vision encouraged adherence.

Table 7 Overview of treatment impact domains reported in the literature and by patients/caregivers and ophthalmologists during the interviews
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Concept Saturation

At the symptom level, saturation was achieved for the total sample, with only three new symptom concepts emerging in the final set of interviews: light sensitivity, objects appearing to move, and itchy eyes. Light sensitivity was only reported in one article and the remaining symptoms were not reported in the literature as symptoms of amblyopia, thus may be due to co-occurring condition(s). Similarly, for impacts, saturation was closely achieved, with impacts on hobbies (daily activities) and communication (social functioning) emerging in the final set of interviews. This suggests that both symptom and impact concepts had been sufficiently explored.

Discussion

The overall objective of this study was to explore the experience of amblyopia, including symptoms, functional impairment, wider HRQoL impacts, and treatment experience, in adult and pediatric populations. Although there is extensive research in the amblyopia field, most of the literature focuses on the psychosocial impacts associated with traditional treatments (such as patching) or associated conditions (such as strabismus) [10, 30,31,32]; evidence specific to the patient experience of amblyopia alone is limited. As such, the present study sought to address this gap by exploring the patient experience of amblyopia in HRQoL domains.

Across the qualitative interviews, patients, their caregivers, and ophthalmologists reported several core visual function symptoms, including (but not limited to) blurred vision (reduced VA), impaired depth perception, impaired peripheral vision, and double vision. Such findings are broadly consistent with previous literature, given that amblyopia is primarily characterized by reduced VA [1], although impaired depth perception (stereopsis) is also common, particularly in strabismic amblyopia [2, 3, 5]. However, peripheral vision is less commonly reported in relation to amblyopia [5], and double vision (diplopia) was only reported in relation to amblyopia in the SML studies [17]. In the literature, double vision has been reported as a side effect of binocular treatments such as video games and patching [33]. Double vision can also be associated with other comorbid eye conditions such as strabismus [34], and could therefore be related to an underlying condition rather than amblyopia. However, in the current study, interview participants, both with and without strabismus, reported double vision in isolation of treatment use, providing evidence that it can occur during habitual binocular vision. However, it should be acknowledged that experiences of double vision may be closely associated with blurred vision where images overlap [35], as such, findings should be interpreted with caution. Furthermore, some secondary symptoms (such as head tilt and dizziness) and many of the causal/comorbid ocular conditions identified in the disease model were only reported in the SML studies [17]. Given that clinician confirmation of diagnosis could not be obtained for the patients using social media, these findings should also be interpreted with caution.

As indicated in the literature, patients’ perceptions regarding the functional impact of amblyopia in daily life have not been explored extensively [5]. The current study offers in-depth insights into the range of HRQoL impacts. Visual function symptoms were reported to have a considerable impact on vision-dependent activities including daily activities (e.g., reading, using/viewing digital devices, driving) and physical functioning (e.g., difficulty moving around/navigating). Such functional impairments of amblyopia have been previously documented, particularly in relation to impaired stereopsis [6, 36]. Consistent with previous literature [6, 15], amblyopia was also reported to impact broader domains of HRQoL including work/school, emotional well-being, and social functioning. This study supports the occurrence of these impacts from the caregiver and ophthalmologist perspective, as well as the patient perspective, therefore offering additional insights compared with previous literature. It should be noted that it can be difficult to distinguish the impacts of amblyopia from those caused by refractive errors (e.g., myopia), particularly when exploring experiences qualitatively with patients [6, 37]. While this study reports impacts reported by participants irrespective of amblyopia type, the study did aim to explore impacts experienced under best-corrected VA conditions (i.e., when wearing glasses, if needed). The findings demonstrated that while some patients were potentially impacted due to a comorbid eye condition (e.g., those who discussed an impact when they were not wearing their glasses only), there were others who were impacted irrespective of correctives, indicating that it was likely an impact of amblyopia. These findings confirm that psychosocial impacts are not only related to treatment, as previously documented [8, 10, 31, 32], but are also apparent outside of treatment use and likely due to amblyopia.

A range of treatments were reported to be used by patients including patching, eye drops, and glasses, although each treatment was associated with limitations or negative impacts. Treatment was reported to have a significant impact upon emotional well-being (e.g., feelings of sadness, frustration, and low self-esteem) and social functioning (e.g., bullying and social stigma, particularly in relation to patching and glasses). Certain treatments, particularly patching, also physically affected patients by causing discomfort or pain, as well as difficulty moving around/navigating while wearing the patch. Some of these impacts were mentioned as barriers to treatment use, leading to poor treatment adherence. Previous literature has documented similar findings, particularly in relation to patching [8, 38]. Such evidence can further support the emergence of binocular treatments such as video games which may mitigate some of the known impacts of visible treatments.

A key strength of this study is the use of comprehensive qualitative methods to explore the experience of amblyopia: a targeted review of published literature, followed by review of SML study findings, and conduct of in-depth interviews allowing for further exploration and consolidation of existing evidence. Importantly, concepts reported during the interviews were largely aligned with those identified in the literature, providing valuable insight into concepts that are important to amblyopia populations. Moreover, a multi-stakeholder approach was employed, meaning the disease model was informed by the published literature, patients, caregivers, ophthalmologists, and expert clinicians in the field of amblyopia, ensuring various perspectives were sought. Therefore, this study provides a valuable addition to the existing literature, which largely focuses on the patient perspective.

However, findings should be interpreted considering the study limitations. Although the interview sample included patients with a range of amblyopia diagnoses and severities, there was less representation of patients with a diagnosis of amblyopia due to a combined mechanism (strabismic and anisometropic) and those with severe amblyopia. This may limit the generalizability of the findings across different clinical presentations of amblyopia. However, the patient sample did have some representation of other key demographic and clinical characteristics. Notably, the sample had good representation across the age spectrum, ranging from ages 4 to 72 years, with fairly equal representation of different age groups. Concept saturation was also closely achieved, suggesting the sample size was sufficient. Given that the published literature and SML studies had global representation and the qualitative interviews were conducted in the US, France, and Germany, the findings can also be carefully extrapolated across countries and cultures. Further, it could also be argued that the clinician interview sample was limited, as only ophthalmologists were included. This is likely because amblyopia in Europe is treated primarily by ophthalmologists and orthoptists, rather than optometrists. Nevertheless, clinical experts who provided input during the study were based in the US, UK, and Australia, and included a pediatric optometrist, which ensured diverse professional views were obtained from across a range of countries. Furthermore, although the proportion of participants from each age group reporting on the various impact domains was generally consistent, apart from school and work impacts, these findings should be interpreted with caution as the sample size can be considered too small for determining differences between subgroups. It could also be argued that the disease model does not outline the relationships between concepts and how they interact with each other; however, the model does provide a comprehensive overview of the patient experience of amblyopia which is currently lacking in the literature.

Conclusions

The study findings make an important contribution to the literature by providing valuable qualitative insights into the adult and pediatric experiences of amblyopia from a multi-stakeholder perspective. The findings supported the development of a disease model providing a comprehensive depiction of the experience of amblyopia and its treatments. It is important for patients, caregivers, and treating clinicians to understand the substantial and multifaceted impacts of amblyopia, and not only its treatments, which can support patient–clinician interactions in clinical practice when managing amblyopia and prescribing treatment. Further, these findings have also been used to critically assess existing clinical outcome assessments (COA) for use in amblyopia populations and ultimately supported the development of new outcome measures that will help demonstrate how interventions improve symptoms and function, which is necessary to support programs which aim to identify and treat amblyopia [16, 39].