Discussion
The number of patients enrolled in TS (9938) are from a larger pool of customers undergoing a comprehensive optometrist vision examination (328 407), which accounts for 85% of the total number of customers for vision examinations. As the optometrist comprehensive vision examination is offered at no additional charge, the authors believe the most likely explanations for the remaining customers (15%) are: age less than 16 years old, customers already enrolled into the national eye care system or customers, who simply didn’t have the time or desire for further testing.
Posterior segment diagnoses were similar to what is shown in other national studies.19–26 However, a relatively high number of bilateral papillary oedema patients were observed in this study; a likely consequence that patients with ‘headache’ seen by GPs are often sent directly to an optometrist.
The most common TS referral diagnoses to the general ophthalmologist were glaucoma (diagnosed by evaluation of optic disc, IOP and visual field) and glaucoma screening (patients with severe risk of glaucoma development), which accounted for a total of one-fourth of all patients referred within a normal waiting time (non-acute). The overall prevalence of glaucoma in Denmark is estimated to 3.76% in the age group above 50 years and close to 50% of all primary open angled glaucoma patients are estimated to be unrecognised. This study also highlights that unrecognised glaucoma is an issue that needs further awareness.27–31
Three per cent of the total number of patients undergoing an optometrist comprehensive vision examination in Louis Nielsen A/S were referred for ophthalmologist review in TS in this study. This was consistent with the overall optometrist referral rate in Denmark, and can vary tremendously between countries, from 3% to 14%.19 20 23 25 Thus, we consider a posterior segment disease referral rate between 2.5% and 4% to a TS as adequate, while, along with such a TS, a referral-ratio between 0.5% and 1.0% to the national eyecare system would be considered sufficient.
To our knowledge, TS is the world’s largest optometrist-ophthalmologist cloud-based e-referral platform based on the number of reviewed patients. It is particularly unique due to the fact that Louis Nielsen A/S with its high customer market share, close to 47% and widespread locations across the country, represents patients from different demographic and socioeconomic backgrounds. In addition, Louis Nielsen A/S is a major employer of Danish optometrists graduated from either of the two Danish optometry colleges.30 32 Though the results may be extrapolated to the overall Danish optometry competency, the authors advise caution in generalising the findings to the overall Danish optometry standard due to lack of demographic information on the national optometry cohort. Further the authors also acknowledge that the selected minority of Danish optometrists that are involved in the healthcare sector are differently qualified. Also previous research from the UK has indicated that there are differences in the outcomes from eye examinations conducted in independent and corporate practises.33 34 However, a recent questionnaire study in Northern Europe (Denmark, Sweden, Norway, Finland and the Netherlands), concludes that there is a similar level of optometry competency across the countries and further there is only a minor difference between new and experienced optometrists with more than 5 years of practising.35 Supported by these factors, the authors suggest that this study is highly relevant for any optometry retail company in the region.
As all major optical companies have implemented fundus cameras, non-contact tonometers and automated perimeters,12 36 this study provides critical outcome measures of what it would look like, if TS was to be implemented on a nationalwide scale. Though the initial pilot study supports the study referral outcomes, the authors advice some caution in extrapolating the findings and suggest that the TS implementation reduced the number of referrals with maximum 8000 patients in the study period.
Clearly, an up to 81% reduction of referrals to the primary and tertiary eye-care sector with the TS setup is remarkable, but it does not imply that optometrists are referring only false positive patients. In fact, this study demonstrates that only 14.4% were normal cases. The consequence of the widespread availability of newer technological instruments is the increased detection of asymptomatic pathological and moderate-to-risk findings that do not require medical intervention (eg, glaucoma screening patients).15 In these cases, depending on risk of disease transformation, the patient would be stratified for follow-up in-house either with or without TS. In both follow-up patterns the optometrist would be provided with a patient-specific examination, follow-up and action plan by the TS ophthalmologist. Some countries, as the UK, have developed collaborative hospital eye service (HES)-referral guidelines in order to structure the referrals from optometrists. However, studies evidently point out that guidelines alone do not sufficiently address the number of unnecessary referrals.17 Cameron et al found that 37% of all optometric HES-referrals were false positive within the NHS. Further, Kern et al reported that the newly implemented optometrist-ophthalmologist e-referral platform at the Moorfield’s Eye Hospital, based on 107 patients, shows a reduction of 50% in referrals from optometrists, in spite of implemented HES guidelines. Similarly, we also believe it is crucial to acknowledge that the national eye care should focus on the true ill patient, which becomes more achievable with new models, as demonstrated.
The authors, therefore, suggest that the TS setup provides a relevant stratification model for the moderate/high risk or asymptomatic non-treatable conditions, with a closed in-house telemedical follow-up service and lean referral pathways for the treatable conditions. The average time from the patient referral to review by the TS ophthalmologist was immediate by phone service in acute patient cases and averagely close to only 1.2 days in suspected non-acute patient cases. In acute situations, for example, papillary oedema and retinal detachment, patients were directly contacted by the TS ophthalmologist and admitted to the relevant tertiary clinics (neurology or ophthalmology). This service further shortens the otherwise cumbersome traditional patient healthcare pathway, where patients often have to be examined by both the GP and general ophthalmologist (primary sector) in order to be referred to the tertiary centre. All referred patients benefit from a TS ophthalmologist written e-referral letter uploaded to the national referral platform (REFHOST), making the e-referral available for any healthcare authority in Denmark. This provides a better opportunity for the general ophthalmologist to triage the patient, which may reduce the time for review and treatment, for example, for subacute diagnoses as wet-AMD where waiting time causes visual impact.37
Telemedicine in ophthalmology is a very well proven concept with several well-run services as for AMD and diabetic retinopathy.38 However, telemedicine should not only serve relevantly in ophthalmology units, but also as a well-suited model for optometrist posterior segment referrals. The optometrists in all the Nordic countries have in recent years implemented instruments for posterior segment investigation, and newer technologies are becoming increasingly more affordable, for example, UK Specsavers (Saint Andrew, UK) implemented optical coherence tomography (OCT) devices in all of its 740 locations.39 Due to the general life span increase among their populations, Nordic and British societies as well are struggling to manage the increased number of patients. Hence, it is highly relevant to find a cost-effective solution. This telemedical setup proves to be an efficient system to improve the referral to the healthcare system. Further, the authors believe this service may serve as a fundament for implementation and validation of newer technologies, that are based on the concept of pattern recognition and deep-mind based automated diagnoses with OCT and fundus technology.38 40–43
Nevertheless, there are some limitations in this study, which are essential to address in future studies. Though it was not the aim of this study to directly evaluate the optometry competency, it is highly relevant to evaluate the optometrist’s diagnostic precision level in various diseases over time and to investigate the false negatives in the optometrist cohort. Also additional patient information is relevant, for example, visual acuity and pharmacological history, in order to increase our understanding of the results. Further, it is relevant to characterise the referrer′s as well as the reviewing ophthalmologists more individually, and based on other factors such as years of experience and qualifications. This kind of demographic information on optometrists are necessary in order to compare findings with other cohorts.
The knowledge from such future studies can be utilised in continuous educational programmes.
In conclusion, we report the results from the largest e-based optometrist-ophthalmologist referral platform study to date. Overall, posterior segment disease referrals to the existing healthcare system can be drastically reduced. This study demonstrates that new healthcare models, which focus on a risk-stratified approach with optimal use of technology, change of working patterns and continuous education, can further optimise the healthcare system.