The study commenced with a school-based cross-sectional study to determine the prevalence of URE in low-resource schools in the Free State Province, South Africa, between July and September 2023 [30]. In consultation with a statistician, a single population proportion formula (n=(Z1 − α)² (P (1 − P))/d²) were Z1-α (the 95% Confidence Interval) of 1.96, P (Prevalence determined in a previous South African study [31]) of 0.206, and d (the margin of error, the absolute precision) of 0.05 was used to calculate the initial sample size of 1,008 learners across four districts. A stratified multistage random sampling was employed to select schools and participants. The results unveiled a prevalence of 27.1% (n = 233, 95% CI, 24.2–30.1)³⁰. Thabo Mofutsanyane was the largest district and had the highest prevalence of URE (57.9%, n = 135) in the Free State province.

Upon URE diagnosis, all learners, together with their parents/guardians and class teachers, were asked to participate in a descriptive, cross-sectional survey using an adopted and piloted questionnaire. A total of 192 out of 233 learners, 132 out of 233 parents, and 23 out of 255 class teachers returned their completed questionnaires at baseline between July and September 2023. Each group of participants has their specific questionnaire adopted from previous studies [25, 32, 33]. The questionnaires covered barriers to the uptake of spectacles identified by literature as affordability, accessibility, availability, acceptability, and knowledge and/or awareness [32, 34–38]. Design and validation of the eyecare health promotion.

A clear understanding of local barriers is indispensable to effective health promotion interventions [39, 40]. The barriers phase revealed that the majority of participants failed to identify most eye problems and never had eye examinations beforehand. Participants viewed spectacles as being expensive, possibly due to the unemployment rate, while some were oblivious of where eyes are examined. Eye problems were presented at inappropriate and ill-equipped facilities, such as clinics, possibly due to their availability and easy access in every community at no cost. Eyecare services were reported to be unavailable and/or inaccessible.

Using a methodological study, the eyecare health promotion (EHP) intervention was designed based on two guiding frameworks: the Ottawa Charter and the Health Belief Model (HBM) [12, 27]. Both these frameworks previously yielded positive outcomes [12, 27]. The HBM constructs were used to develop and validate the EHP. A total of seven questions addressed perceived susceptibility and benefits, 13 measured perceived severity, and three measured perceived barriers for both expert groups. Cues to action had six and three questions, while self-efficacy was measured by six and two questions for optometry and public health experts, respectively. The EHP materials, in collaboration with a professional graphic designer, were drafted for expert validation. The materials included a Microsoft PowerPoint presentation, pamphlets, and posters. Posters are included as Supplementary Appendix I.

A total of six experts, three from optometry and three from public health, with a minimum academic qualification of a PhD, were invited to validate the EHP using Content Validity Index (CVI). The results were consolidated on Microsoft Word, and the calculation of the I-CVI and SCVI was performed as recommended [41]. An I-CVI greater than or equal to 0.78 illustrated that the constructs were relevant to and representative of the targeted concept of promoting eyecare. The analysis achieved an I-CVI of 0.95 (Table 1). This phase was conducted between February and August 2024.

As aforementioned, the prevalence of URE indicated that the Thabo Mofutsanyane district had the highest prevalence, and that the majority of its schools were in quintile one (Q1), making it the most vulnerable district. Quintile one schools are classified as the poorest schools located in socioeconomically disadvantaged communities, and receive the largest proportion of government subsidies. At the same time, its learners are exempt from paying school fees [42]. As a result, this district was purposively selected for the implementation of the intervention.

All twenty schools in the district that had participated in the prevalence of URE and barriers phases were written on slips of paper and placed in a bowl. The first 10 schools randomly drawn were assigned to receive the intervention and comprised 67 learners, 52 parents, and 9 teachers. The remaining 10 received no intervention and had 42 learners, 21 parents, and 8 teachers. The questionnaires assessed participants’ knowledge, awareness of eyecare, and perceptions of eyecare in relation to accessibility, availability, affordability, and acceptability of services.

In alignment with the Ottawa Charter’s principle of service reorientation, all learner participants had undergone eye examinations. At the EHP implementation, participants were provided with spectacles at no cost. This eliminated the affordability barrier and facilitated compliance with spectacle wear. The EHP further sought to enhance personal eyecare skills and strengthen school community action through reinforcement tools, including pamphlets for participants, posters for schools and live presentations delivered by the researchers. Access to an optometrist was also established, thereby fostering a supportive environment. The intervention did not address the policy development component of the Ottawa Charter.

The treatment content included the importance and benefits of routine eye examinations: where and how to access eyecare services, the costs of obtaining these services, and visual ergonomics. The implications of blurred vision and recognition of common ocular symptoms were included. The overarching aim was to equip the participants with foundational knowledge of ocular health and promote regular eye examinations. The intervention was presented in layman’s language, supported by graphics, video clips and images. The content was delivered in either English or Sesotho, the participants’ vernacular. Similar approaches proved effective in prior studies [9, 22, 27].

For implementation, the researchers coordinated with the designated liaison teacher at each school. Arrangements included the school principal’s approval, securing a room large enough to accommodate all participants, and notifying parents. The presentations were projected on a large screen, followed by a question-and-answer session. Pamphlets were distributed to participants, and posters were placed in the schools. The evaluation followed established practices [9, 22, 23, 27]. Following the intervention, its effectiveness was evaluated 6 months later, in accordance with the literature [9, 15, 28, 29]. The post-intervention study was conducted on learners (n = 40), parents (n = 35), and teachers (n = 8) in the experimental group and 26, 19, and 8 learners, parents, and teachers in the control group, respectively (Figure 1). The attrition rate was 31.7% due to the unavailability of learners who had since left the respective schools.

As outlined, the intervention was designed to increase knowledge, enhance uptake of eyecare services, and ultimately reduce the prevalence of URE. Effectiveness was assessed by comparing changes in knowledge levels between the experimental and control groups from baseline to postintervention. Intervention material is provided in Supplementary Appendix I (English version only).

The data were captured and analysed using the Statistical Package for Social Sciences (SPSS version 27) in consultation with a statistician. Descriptive statistics (frequency distributions, proportions, and summary tables) were used to present baseline characteristics and overall response patterns. For inferential analysis, the McNemar chi-square test was used to assess changes in paired categorical data between pre-and post-intervention responses. The level of significance was set at p < 0.05 for the McNemar chi-square test.

Ethical approval for the study was obtained from the Biomedical Research and Ethics Committee of the University of KwaZulu-Natal (BREC/00005522/2023). The study was conducted in accordance with the principles of Good Clinical Practice and the Declaration of Helsinki. All participants were provided with an information sheet outlining the purpose, procedures, and requirements of the study. The document emphasised that participation was entirely voluntary, that participants could withdraw at any stage without penalty, and that all information would remain strictly confidential and anonymous. Written informed consent was obtained from all participants before enrolment.

A key strength of this study is its use of a tailor-made, culturally and contextually informed health promotion that was implemented at the school-community level [9, 13, 15, 29]. This enhanced the ecological validity of the findings by embedding the intervention in a real-world educational setting. The inclusion of multiple stakeholders: learners, parents, and teachers, allowed for a more holistic understanding of how eye health knowledge is disseminated and retained within communities [9, 15]. The use of well-established theories and the validation of the intervention ensured that the EHP was sound [15]. The study delivered its EHP in a manner consistent with the literature, including the 6-month follow-up period [7, 9, 13–15, 29].

This study is subject to several limitations. First, the relatively small sample size limits the generalisability of the findings and reduces the power to detect subtle differences across groups. Loss of participants at follow-up further exacerbated the generalisability of the findings. Second, while the EHP explicitly stated that optometric services are not available at local clinics, this message was not retained by many participants, suggesting either limitations in the clarity of communication or the overriding influence of entrenched health-seeking patterns. The reliance on self-reported data may have introduced response bias, particularly in questions regarding health-seeking behaviour.⁴³ Finally, the study did not report the spectacle wear compliance, which formed part of the intervention, and thus did not report the behavioural change [13].

The study was conducted among participants diagnosed with URE, their parents/guardians, and teachers. Eyecare health promotion can be broadened to include the entire school community and can be conducted annually. Future EHPs could be conducted by trained school community members, as has been proven successful in Tanzania [7]. The EHP must remain tailored to the respective communities. Eyecare services need to be brought closer to the people, in their communities. Additionally, there is a need to train teachers not only on symptoms but also on the associated psychosocial and academic impacts of vision problems. This training could be integrated into their undergraduate programme and disseminated in ongoing workshops.

Notwithstanding the limitations related to small sample sizes, reliance on self-reports, and short-term follow-up, the findings support the feasibility and value of implementing eye health promotion in school settings. Although the study did not assess the subsidised spectacle wear compliance in line with the literature, it improved participants' knowledge of eye-related signs and symptoms. [15, 44] Despite these constraints, this study demonstrated that targeted eye health promotion can effectively address misconceptions, enhance symptom recognition, and promote preventative behaviours. Future interventions that are tailored and large in scale, sustained over longer periods, and supported by the integration of basic eye-care services within primary healthcare facilities are likely to achieve greater and more durable impacts.