Abstract
Teledermatology is often classified according to the mode of delivery into three categories: (1) store-and-forward (S&F) (2) realtime, or (3) a hybrid model, where both S&F and realtime techniques are employed. We believe that this approach is no longer sufficient in the evolving field of teledermatology. At its outset, teledermatology mainly concerned communication between physicians and specialists 1 and so the field was mainly centred on the providers’ perspective. However, as a result of advances in communications technology, patients can now communicate directly with dermatologists. Various health-care workers can also participate directly or indirectly in the delivery of teledermatology services. This expansion of teledermatology means that teledermatology needs to be explained in a broader context.
We have therefore examined teledermatology from the perspective of health-care delivery. On this basis, we categorize teledermatology into: (1) consultative, (2) triage and (3) direct-care models. The three models and their process flows are described below.
Consultative model
In the consultative model, dermatologists serve as consultants who evaluate the patient and provide specific recommendations to the referring doctor. This is a collaboration between the referrer and the specialist. While the dermatologist provides advice via teleconsultation, patients remain in the care of the primary care provider (PCP) throughout their treatment. The consultative model is typically practised using either store-and-forward techniques or realtime videoconferencing. At present, the consultative model is the most common health-care delivery model in teledermatology in the US.
When the consultative model is practised using the S&F mode, medical staff at the referral sites obtain the patient's history and photographs of the skin lesions. After transmission of this information, the dermatologist evaluates the relevant clinical data and completes a formal assessment and recommendation, which are then transmitted to the referring provider. The referring provider assumes the responsibility for discussing the dermatologist's assessment with the patient and implementing the recommendation. 2
When the consultative model is delivered using the realtime mode, the dermatologist communicates directly with the patient through videoconferencing. The dermatologist obtains the clinical history directly from the patient and examines the patient's skin in realtime. The referring provider may or may not be in the room when the consultation occurs. The referring provider assumes the same responsibility for carrying out the dermatologist's recommendations.
Process flow
The advantages of the consultative model are well documented. 1,2 The benefits include improving access to underserved populations, reducing unnecessary clinical visits, and allowing flexibility in the dermatologist's work schedule because of the S&F modality. 1,2 A less well-studied but frequently recognized benefit of the consultative model is its ability to improve the referring providers’ diagnostic skills and therapeutic repertoire. 1 Patients treated through the consultative model have similar clinical outcomes to those treated face-to-face. 3
The drawbacks of the teledermatology consultative model have rarely been discussed. 2 When teledermatology consultations are delivered in S&F mode, the dermatologist cannot have a realtime dialogue with the patient. Without direct communication between the two, the dermatologist has to depend on the quality of the clinical history and digital images for formulating a diagnosis and making treatment recommendations. If the relevant clinical history is missing or the image quality is poor, the dermatologist may be severely limited. Furthermore, the lack of realtime communication between the patient and dermatologist does not allow an interactive patient-physician relationship to be developed.
Dermatologists who practise consultative teledermatology in realtime, and sometimes the referring providers, build a more therapeutic and collegial relationship. However, realtime care delivery requires greater administrative support and offers less scheduling flexibility for the patient and the dermatologist. In addition, the image quality is limited by the available communications bandwidth and the videoconferencing equipment, which can pose considerable problems.
Triage model
In health-care delivery, the triage model is broadly defined as the process of prioritizing patients based on the severity of their illnesses. 3 This allows health-care resources to be distributed efficiently when insufficient resources are available. In teledermatology, we define the triage model as the process by which dermatologists review new cases (usually in S&F mode), prioritize the patients requiring in-person consultation, and decide the timing for these evaluations. This model may be collaborative between the PCP and specialist in some cases, but moves responsibility for the patient to the dermatologist in others.
In the triage model, the referring provider is typically less discriminatory regarding which cases to send to the dermatologist, and the dermatologist's level of assessment for individual cases varies. 4,5 For example, in a typical triage model, the patient visits a PCP, who arranges to have the patient's skin condition photographed. The photographs and history are sent to the dermatologist, who assesses the skin condition, prioritizes the severity of the illness, and decides whether the patient needs to be seen in-person or can be managed by the PCP. The dermatologist will usually assume responsibility for the patient if he or she is seen in-person. Otherwise, the dermatologist relays the assessment and recommendation to the PCP who will follow up the patient. The goal of the triage model is the categorization of patients.
Most literature describing the triage model of teledermatology delivery derives from European practices, especially in the prioritization of patients presenting with cutaneous malignancies. 5,6 For example, Ferrandiz et al. evaluated a triage model in southern Spain, where dermatologists evaluated digital pictures of patients from six primary care centres and prioritized their visits to the skin cancer unit at a public university hospital. 5
Process flow
When performed efficiently, the primary advantages of the triage model are that it distributes scarce specialist resources efficiently and reduces unnecessary in-person visits to dermatology clinics. Studies have found that 13–58% of dermatology clinic visits could have been avoided with a triage model based on the S&F modality and 74% of potentially cancerous skin lesions were manageable without a dermatologist. 1,6 Compared with conventional referrals, the triage model appears to reduce the length of time to diagnosis and treatment. 4,5 For example, Spanish patients at primary care centres who received triage through teledermatology waited an average of 76 days less to see a dermatologist in-person at a university hospital than those receiving a conventional referral. 4 Because the triage model inherently requires less detailed evaluation and management from the dermatologist, the depth and quality of assessment vary for patients not requiring in-person evaluation. In practice, there can be considerable overlap between the triage and consultative model, especially if the dermatologist provides thorough assessment and recommendations.
Direct-care model
Recent developments in technology allow new models of teledermatology. For example, high-resolution digital cameras and mobile phone cameras enable suitably-trained patients to take high-quality photographs of their skin lesions. This affords opportunities for patients to seek and receive treatment directly from a specialist. 7
To date, the direct-care model has been used primarily in research. 8 In the direct-care model, the dermatologist assumes the responsibility for providing care to the patient, including evaluating the skin condition, relaying the treatment recommendations to the patient, prescribing medication and ordering laboratory tests. In this model, the communication and decisions regarding the dermatology care flow directly between the patient and the dermatologist. It is usually at the discretion of the dermatologist whether he or she would like to keep the PCP apprised of the patient's treatment.
The preferred modality for practising direct patient care is S&F. 8 In a study by Watson et al., investigators found that patients with acne managed online had equivalent clinical outcomes to those who were managed in conventional face-to-face office visits. 8
Process flow
The direct-care model has the same advantages as the other models of teledermatology, including improved specialist access to patients, reduction in travelling time and cost, and the potential for cost-effective care. 8 The unique advantage of direct-care is the reduction in the clinical and administrative workload for the referring providers, because the dermatologist assumes the clinical responsibility for the patient.
Some challenges of practising the direct-care model are common to all forms of teledermatology, including ensuring data security and appropriate image quality. 7,8 There are three distinct areas that need to be addressed to make direct-care sustainable. First, when direct-care is delivered through the S&F modality, the dermatologist needs to consider ways of establishing a satisfactory patient-physician relationship. Without a trusting relationship between the patient and the dermatologist, online communications may be misconstrued, which may lead patients to become dissatisfied with their care. Ideally, direct-care teledermatology is practised in follow-up care settings, after the patient and the physician have had direct dialogue either in person or by videoconferencing. For example, one study found that after an initial in-person consultation took place, direct-care teledermatology allowed the effective follow-up management of ulcers. 9 Second, patients must be well trained in taking high-quality skin images to ensure that the images are satisfactory for diagnosis. Third, because no US legislation mandates reimbursement for direct-care teledermatology, the dermatologists and patients must arrive at an agreement for payment of services.
Discussion
Our proposed classification of teledermatology is based on three different health-care delivery models: (1) consultative, (2) triage and (3) direct-care. The consultative model can be used in a variety of practice settings where dermatologists are not easily accessible or available. The consultative model can be used for initial and follow-up care of patients with a range of skin conditions. For example, in California, the consultative model is especially well suited for the prison population, to save resources otherwise required to transport prisoners over long distances to see specialists. 10
The triage model may be best for prioritizing urgent cutaneous eruptions or high-risk skin lesions that require timely in-person evaluation by specialists. For example, the triage model can be used to prioritize patients with cutaneous malignancies or those with serious eruptions, such as severe drug reactions, exacerbation of immunobullous diseases, and infections in immunocompromised hosts. 4,5
The direct-care model seems best suited for follow-up care of chronic skin diseases, after the patient and specialist have had direct communication either in person or through videoconferencing. With training, patients with chronic skin disease can take high-quality images of their skin diseases and transmit the images to specialists for evaluation. 8 The direct-care model may not be well suited for diagnosing skin diseases in patients with whom the specialist has no prior relationship. This is because patients who do not habitually take images of their skin condition may not be able to capture images of sufficient quality for diagnosis. Furthermore, without the context of a strong patient-physician relationship, online communication between the two parties could be misconstrued and lead to undesirable clinical outcomes and dissatisfaction.
At present, the consultative and triage models are widely practised by dermatologists, while the direct-care model is likely to be more relevant in future as the field advances. These three models highlight the types of teledermatology services that are provided to patients without dependence on technology. This categorization will be useful to health-care policy makers because it is technology independent.