Our results showed that the implementation of a centralized, remotely operated referral management system reduced both the number of cases on waiting lists and waiting times of high-risk patients for specialized care, in all analyzed localities. The consistency of results obtained across the localities included in this study is relevant for the interpretation of findings, since it indicates that telehealth interventions may be effective when supporting the referrals of cases from primary to specialized care in diverse settings within a universal health system, regardless of socioeconomic and demographic characteristics of the involved localities.
Brazil is a country with a vast territory marked by socioeconomic disparities. A diversity of decentralized strategies is implemented throughout the country to guide the referral process from primary care. This diversity imposes challenges to regional healthcare leaderships. Baseline measures highlight such heterogeneity: in Porto Alegre, capital of the southernmost Brazilian state, the number of cases on waiting lists were significantly lower (28,772) than the number of cases in Belo Horizonte in the Southeast Region (36,359). By far, the state of Amazonas, in the North Region of Brazil, presented the largest number of baseline cases (61,170). Due to its peculiar geography, it may be difficult to access healthcare services, since it is not uncommon for a patient to have to travel hours or days by boat to attend a specialized consultation . Therefore, it was expected that the largest number of cases in the baseline would be in the Amazonas state. Furthermore, these three localities differ in relation to the proportion of population covered by private health insurance, population density, Gini ratio, human development index and per capita gross domestic product. However, despite all these differences, a reduction in the number of cases was consistently observed over time in all localities.
The pronounced reduction of cases in waiting lists after the implementation of strategies, such as e-consultation between PHC providers and trained family doctors and specialists, reflects the fact that many cases referred to specialized care could be avoided with proper support to PHC providers. Previous studies conducted in Brazil have shown that 20.6 % of referrals to specialized care could be avoided if properly attended at the PHC unit . One can assume that the referral of such cases to specialized care is at some extent responsible for the overburden and long waiting times at the secondary level of care.
In Porto Alegre, the utilization of risk assessments protocols allowed for a significant reduction in waiting times for high-risk patients but not for those at a standard risk. Out of the three locations analyzed, Porto Alegre has the longest experience in using telehealth risk assessment protocols to manage PHC referrals. This may explain why high-risk patients benefited more in the reduction of waiting times for specialized consultations, confirming the usefulness of a protocol-based risk assessment to increase the equity of the system.
In Brazil, pioneering local initiatives involving telehealth strategies to optimize referral management to specialized care have been conducted, such as the TelessaúdeRS program and the implementation of teleconsultations in the primary healthcare system in Belo Horizonte [26,27,28]. These programs include a wide range of interventions, such as telediagnosis and e-consultations . Applied interventions resulted in the reduction of cases in waiting lists and in the waiting time for high-risk cases, as also observed in the present study . The positive results of the TelessaúdeRS program ultimately led to the expansion of activities to other regions of the country, originating the Regula Mais Brasil project.
There is previous evidence that telehealth strategies, including e-consultations, risk and tele-triage based on risk assessment protocols can reduce waiting lists for referrals to specialized care in countries that do not have universal health systems. In a scoping review on the topic, Caffery et al. concluded that telehealth interventions obviate the need for face-to-face consultations with specialists in 34 to 92 % of cases . However, the model of referral system applied in SUS is probably unique, which hampers direct confrontation of our results with those from studies conducted in other countries.
This study presents several strengths. First, to the best of our knowledge, this is the first study aiming at the assessment of effects related to telehealth in multiple localities in Brazil. We analyzed data of cases waiting for specialized care in multiple medical specialties from two cities and one state, over a period of six months. The number of cases in waiting lists were extracted directly from the databases of the referral management systems, and all cases of waiting lists eligible to inclusion in the study were analyzed.
The impossibility of assessing multiple time points before the implementation of the project precluded a time series analysis and represents one of the limitations of this study. It was not possible to accurately assess the time trend before the start of the study nor to exclude the influence of other concurrent co-interventions that may have led to an overestimation of the intervention impact. Furthermore, it was not possible to include data of one of the localities due to the adopted changes of the referral process, concurrently with the intervention . Finally, we opted to analyze a maximum of a six-month post-intervention period to achieve a higher number of waiting lists. It was not possible to make inferences to whether a more prolonged operation would result in further reduction of the number of cases in waiting lists or a ceiling effect would be reached at some point.
Considering the findings presented and the knowledge generated by previous studies, it is possible to conclude that the adoption of telehealth strategies to assist the referral management of cases from primary to specialized care is an effective intervention, resulting in the reduction of number of cases in waiting lists. The implementation of telehealth in this context was successful in all analyzed localities, suggesting that telehealth can be extended to a diversity of settings within universal health systems. However, it must be considered that, for the successful implementation of a centralized, remotely operated strategy for managing referrals in the whole country, it would be necessary to harmonize procedures across jurisdictions at a minimum. In municipalities with decentralized referrals, such is the case of Rio de Janeiro, where PHC providers have become personally responsible for scheduling procedures and appointments since the Reform in Primary Care [32, 33], procedures would have to be reviewed and redesigned to allow the centralized operation of the referral management system, within a patient-centric approach. This would be a major issue to be overcome in the way of achieving standardized procedures in Brazil.