Approximately 9937 separate approaches were made to potential participants (Fig. 1), with a 5.3% click-through to the survey from recruiting emails. A social media campaign resulted in 7019 unique webpage views, 3.0% like or engagement rate, and a request for 37 mailed questionnaires. Participants may have been contacted several times by different organizations.

Consent was obtained for 1036 participants. After removal of ineligible responses, data from 681 participants (51.7% women, mean age 53.5 years (SD ± 15.8)) were available for analysis (Fig. 1). The majority of responses (87.1%) were completed online.

Based on a population frequency of 1 in 2000 individuals [18], Australia’s population of patients with IRD is currently estimated at 13,000 (both diagnosed and undiagnosed), resulting in a response rate of 5.3% of the target population.

Participant characteristics are shown in Table 1. Included adults with IRD (n = 639, 93.8%) were of mean age 54.1 years (SD 15.9, range 18–93), 50.2% female, and most had retinitis pigmentosa (61.8%; Fig. 2A). Responses from 42 (6.2%) parents/caregivers differed significantly from the adult cohort, being younger with mean age 44.5 years (SD 10.7, range 18–76), more likely to be female (73.8%) and disproportionately responding on behalf of individuals diagnosed with cone-rod dystrophy (16.7% compared to 5.8%) and Leber Congenital Amaurosis (11.9% compared to 1.3%, Fig. 2B).

Self-reported diagnoses of respondents to national survey of Australians with inherited retinal disease A adults n = 639, B report of IRD for their dependent by caregivers n = 42.

Adults with IRD reported mean symptom onset age of 22 years (IQR 11–36, range 0–81); 9.1% reported they currently have stable vision, and 66.5% reported visual decline within the past 5 years (Table 1). As expected, parents/caregivers reported earlier symptom onset in their children/dependents (median 3 years, IQR 0–6, range 0–40; p < 0.001).

As expected, people with generalized retinal involvement were more likely to report difficulty seeing at night, bumping into low-lying objects, difficulty adjusting from light to dark (or vice versa), missing parts of vision or noticing peripheral or side vision reducing compared to those with macular disease (p < 0.05 for all comparisons; Supplementary Table S1). Patients with macular only involvement were more likely to report no noticeable symptoms.

Those with generalized retinal involvement were more likely to have previously taken vitamin A (generalized vs. macular: 17.5% vs. 7.1%; p = 0.001). Those with macular involvement were more likely to use herbal remedies (generalized vs. macular: 9.7% vs. 17.3%) for their IRD (Supplementary Table S1).

Overall, 28.3% of all respondents reported participation in medical research in the past (Fig. 3A), and 60.5% had supplied DNA to an Australian IRD database (Fig. 3B). Previous treatment for IRD was reported by 24.5% of respondents (Fig. 3C).

Self-reported attitudes to medical research of respondents to national survey of Australians with inherited retinal disease (total n = 681, adults with IRD n = 639, parents/caregivers n = 42). A Previous participation in medical research of any kind, B previous supply of DNA to an IRD database, C previous treatment for IRD, D perceived barriers to receiving gene therapy for IRD, and E likelihood of consenting to gene therapy if offered for their condition. Responses for the two groups were not statistically different. IRD inherited retinal disease.

Overall, 59.6% of respondents reported one or more perceived barriers to receiving gene therapy (Fig. 3D). The commonest reported barriers were out of pocket cost (30.5%) and fear of side effects (27.0%). Despite these barriers, most participants (91.6%) indicated that they would likely (17.9%) or very likely (73.7%) take up gene therapy if it was available now to them or their family members for their IRD (Fig. 3E).

Collapsed response frequencies to the AGT-Eye for all survey respondents are shown in Table 2, and full responses by respondent type (five-point Likert scale) are shown in Supplementary Fig. 1.

The majority (86.9%) of participants agreed that they understood the difference between a clinical trial and an approved treatment. However, only 28.3% agreed that they had a good knowledge of gene therapy. Most participants reported obtaining information about gene therapy (Section A) from the internet (49.3%) and their ophthalmologist/s (37.9%).

Section B evaluated participants’ self-reported knowledge of gene therapy methods (Table 2). This subscale showed that most respondents were uncertain of the details of the treatment, with the most common response being “neither agree or disagree.” Almost half (47.1%) of respondents correctly indicated that gene therapy and cell therapy are not the same treatment, and 42.4% of respondents agreed that gene therapy for IRDs is generally delivered to both eyes.

Section C evaluated participants’ awareness of potential gene therapy outcomes (Table 2). Most respondents correctly indicated that gene therapy for the eye is a treatment that may slow disease progression (69.3%) and that gene therapy for IRDs will require many years of follow-up with their eyecare practitioner (67%). Most respondents also were aware that their privacy would be maintained if they received gene therapy (70.3%). Most were aware that having gene therapy for their eye condition could still mean passing their underlying genetic condition to future generations, depending on the mode of inheritance (62%).

Section D evaluated the perceived value of gene therapy treatment, including economic considerations. Although 79% of the respondents agreed that government subsidy of their gene therapy treatment would be an effective use of taxpayer money, only 42.9% of respondents indicated that the government, and 46.1% their private health insurance, should pay all costs of their gene therapy. Three quarters of respondents would consider traveling interstate to access gene therapy (76.5%), and 62% would consider a payment plan for their gene therapy.

Table 3 shows the mean scores across the AGT-Eye subscales, according to respondent characteristics. Subscale responses ranged from 2.4–3.7 (out of a maximum score 5), indicating uncertainty or neutrality of responses. There were no differences between the AGT-Eye subscale scores between males and females.

Respondents who indicated that they were likely/very likely to take up gene therapy scored higher on information sources (Subscale A; mean score 2.5 [SD: 0.90]), than people who were neutral (mean score 2.3 [0.82]) or unlikely/very unlikely to take up gene therapy (mean score 2.3 [0.89]), meaning that they are more likely to have obtained information about gene therapy from a greater number of sources (Fig. 4).

Self-reported sources of information about inherited retinal disease compared with likelihood of accepting gene therapy of respondents to national survey of Australians with inherited retinal disease (total n = 681, adults with IRD n = 639, parents/caregivers n = 42) demonstrating that participants very likely to accept gene therapy if offered had sourced information from multiple sources, most commonly the internet (49%).

Overall, participants scored 3.3 out of 5 for knowledge of gene therapy methods, and 3.4 out of 5 for awareness of gene therapy outcomes. Mean subscale scores for Knowledge of Methods (Subscale B) were higher from respondents who indicated that they are likely/very likely to take up gene therapy (mean score 3.3 [0.42]) compared to those who were neutral (mean score 3.2 [0.36]) or unlikely/very unlikely to take up gene therapy (mean score 3.3 [0.53]; p = 0.036). Respondents with post-graduate degrees scored highest compared to other educational levels on Methods (p < 0.001) and Outcomes (p = 0.003).

Responses to items in the perceived value subscale (Subscale D) indicated that parents/caregivers were more likely to see value in gene therapy for their dependants than adults with IRD (mean subscale score 4.0 [0.44] vs. 3.7 [0.55], respectively, p = 0.002). Respondents who indicated that they are likely/very likely to take up gene therapy also scored higher for perceived values of gene therapy than those who were neutral or unlikely/very unlikely to take up gene therapy (mean scores 3.81 [0.54] vs. 3.60 [0.47] vs. 3.5 [0.59], respectively; p < 0.001). Respondents with post-graduate degrees were more likely to see economic value in treatment (p = 0.043).

Scores of the NEI-VFQ-25, PACT-22 and EQ-5D-5L are shown in Supplementary Table S2. The median composite NEI-VFQ-25 score was 48 (IQR 38–62), from a range from 0 to 100. Responses to the PACT-22 showed high positive beliefs (mean score 95 [IQR: 81–100]), safety (mean score 88 [IQR: 75–94]), information needs (mean score: 88 [75–100]) and need for patient involvement (mean score 75 [69–88]). There were low negative expectations (mean score 42 [33–54]). Parents/caregivers were more likely to have high information needs (p = 0.035) and low negative expectations (p = 0.041) than adult patients with IRDs. Responses to the EQ-5D-5L showed overall utility score 0.81 and visual analogue score 77.

Comparing AGT-Eye subscale scores and other instruments, weak or no correlation was evident between AGT-Eye subscale scores and each of the NEI-VFQ-25 and EQ-5D-5L scores (Supplementary Table S3). For PACT-22 scores, weak positive correlations were observed between AGT-Eye knowledge of methods (subsection B) and awareness outcomes (subscale C) with PACT-22 positive beliefs (ρ = 0.11 and ρ = 0.11, respectively), safety (ρ = 0.10 and ρ = 0.09, respectively), and negative expectations (ρ = 0.20 and ρ = 0.11, respectively). For subsection D, weak correlations were observed between mean scores for AGT-Eye perceived value of treatment (Subscales C) and PACT-22 positive beliefs (ρ = 0.21), safety (ρ = 0.25), information needs (ρ = 0.16), and patient involvement (ρ = 0.21). A weak negative correlation was observed between AGT-Eye Information sources (Subsection A) and PACT-22 information needs (ρ = −0.11).

Comparing composite scores across the NEI-VFQ-25 and EQ-5D-5L instruments, a moderate correlation was observed between each of the NEI-VFQ-25 composite score with the EQ-5D-5L utility score (ρ = 0.57, 95% CI: 0.52–0.62) and the EQ-5D-5L visual analogue scale (ρ = 0.30, 95% CI: 0.23–0.37; Supplementary Table S4).