Of the 2400 physicians included in the study, 51.45% (n = 1235; 95% CI 49.42–53.42) declared working as dual practitioners, while 26.95% (n = 647; 95% CI 25.17–28.79) and 21.58% (n = 518; 95% CI 19.88–23.33) were working exclusively as private and public practitioners, respectively (Additional files 2 and 3). All the prevalence rates and PR confidence intervals addressing sociodemographic and work-related differences between public, private and dual practitioners described in the text were calculated taking the public practitioners as reference (Figs. 2 and Fig. 3).
In the study, 57.5% were males and 42.5% were females (95% CI 55.4%–59.6%; 40.4%–44.6%), in agreement to the general distribution of physicians in Brazil. Most physicians working exclusively as private practitioners or as dual practitioners were males (64 and 58.3%, respectively – 95% CI 60.4%–67.4%; 55.5%–61.1%). Prevalence of male physicians working exclusively as private practitioners was 35% higher in comparison to public assistance physicians (PR 95% CI 1.21–1.51). Conversely, female physicians were 46,3 and 26,4% more prevalent among public practitioners rather than private and dual practitioners, respectively (PR 95% CI 0.6–0.78; 0.71–0.88).
Younger physicians (less than 35 years of age) were 114.7% and 19.5% more prevalent among public physicians than private and dual practitioners, respectively (PR 95% CI 0.38–0.56; 0.73–0.95). Physicians with ages ranging from 35 to 60 years were 30% more prevalent in the dual practice category in relation to the public practice category (PR 95% CI 1.16–1.45), while no significant age difference was found in the prevalence rates between public and private physicians. Physicians above 60 years of age were 96% more prevalent among private practitioners than physicians delivering public services (PR 95% CI 1.58–2.43), whereas senior dual practitioners were 54.4% less prevalent as compared to public practitioners (PR 95% CI 0.51–0.83).
Most physicians included in the study were located at the Southeast region (56%; 95% CI 54%–58%) followed by the Northeast (17.3%; 95% CI 15.7%–18.7%), South (14.8%; 95% CI 13.5%–16.2%), Central-western (7.6%; 95% CI 6.6%–8.7%) and North regions (4.3%; 95% CI 3.4%–5.2%), in agreement to the general distribution of physicians in Brazil. Despite the marked inequality of physician’s distribution across the country, only two regions showed differences in prevalence rates between public, dual and private practice: the northeast region presented higher prevalence of physicians working as public practitioners (72,8%; PR 95% CI 0.44–0.76) when compared to private practitioners, as opposed to the Central-western region, where dual and private practitioners were respectively 59% and 102% more prevalent than public practitioners (PR 95% CI 1.04–2.45 and 1.29–3.16).
Most physicians (64.1%; 95% CI 62.1%–65.9%) reported working at their city of residence (same city). Only 7% (95% CI 6.1%–8.1%) reported working exclusively in a city that they were not living in (different city), while 28.9% (95% CI 27.1%–30.8%) occupied job positions located both at their cities of residence, but also in another city (both). Physicians working in the same city they live were 29% more prevalent among private practitioners than physicians working in public services (PR 95% CI 1.19–1.39). Conversely, the prevalence of doctors working exclusively in a different city in the public sector was 251.4 and 274.7% higher than among dual and private practitioners, respectively (PR 95% CI 0.21–0.39 and 0.18–0.4). Physicians working in both same and different cities were 67% more prevalent among dual practitioners in comparison to physicians delivering public services (PR 95% CI 1.4–1.99).
Most physicians providing private services (including dual or private practitioners) were working at medical clinics and private hospitals, representing 78.2% (95% CI 74.3%–82.2%) of the interviewees; 31.1% reported working at private clinics/ambulatories (95% CI 29.3%–32.8%), and only 5.3% were currently working at private universities (95% CI 4.3%–5.2%).
Physicians providing public services (including dual practitioners and doctors dedicated exclusively to public practice) were more frequently registered at public hospitals (51.5%; 95% CI 49.5%–53.5%), followed by primary care (23.5%; 95% CI 22%–25.2%), specialized care (4.8%; 95% CI 3.9%–5.7%) and public college/university institutions (4.1%; 95% CI 3.3%–5%). Primary care physicians were 46.2% more prevalent among doctors exclusively working as public practitioners than dual practitioners (PR 95% CI 0.6–0.78).
Most doctors reported not working in on-call services (54.5%; 95% CI 52.5%–56.5%). Public practice physicians that provided on-call services were 212.3% more prevalent as compared to private service physicians (PR 95% CI 0.27–0.38). Prevalence of on-call services was similar between public and dual practice physicians.
In relation to the years of medical practice, doctors with less than 10 years of medical practice represented 29.5% (95% CI 27.5%–31.4%), practically the same proportion of physicians with more than 30 years of practice (29.9%; 95% CI 28%–31.8%). Physicians with less than 10 years of practice were concentrated in public services (28% and 127.9% more prevalent than dual and private practitioners, respectively; PR 95% CI 0.68–0.89; 0.36–0.53). Physicians with 10 to 30 years of practice were 49% more prevalent among dual practitioners as compared to their public sector peers (PR 95% CI 1.29–1.72). Physicians with more than 30 years of practice were concentrated among private practitioners (59% more prevalent than the public service physicians; PR 95% CI 1.35–1.87). Nevertheless, physicians with more than 30 years of practice were 77% more prevalent among public practitioners than dual practitioners (PR 95% CI 0.65–0.92).
Weekly workload ranging from 40 to 60 h was reported by 43,1% of the interviewees (95% CI 41.1%–45%); 32.4% reported working more than 60 h per week (95% CI 30.5%–34.2%). Nearly one fifth (19,4%; 95% CI 18%–20.9%) of physicians reported a weekly workload of 20 to 40 h and only 5.2% reported working less than 20 h per week (95% CI 4.3%–6.2%).
Distribution of physician’s workload according to their mode of practice revealed that private practitioners were over-represented in the 20 h per week category (prevalence rate 104% greater than public practitioners; PR 95% CI 1.4–2.96), showing also no dual practitioners in this category. Few dual practitioners dedicate 20 to 40 working hours per week, in contrast to physicians from public services, which are 424.5% more prevalent than doctors dedicated to dual practice when considering this category/interval (PR 95% CI 0.15–0.24). Dual practitioners, however, are more prevalent in the 40 to 60 working hours category (17%; PR 95% CI 1.3–1.32), showing also marked prevalence among physicians working more than 60 h per week as compared to public practitioners (139%; PR 95% CI 1.99–2.86). Besides dual practitioners had presented the most extended weekly workloads, public service physicians working more than 60 h per week were 46.2% more prevalent than private practitioners (PR 95% CI 0.53–0.89).
Of all physicians included in the study, 68% held a specialization (95% CI 66.3%–69.8%). Specialists were more prevalent among dual and private practitioners than physicians delivering public assistance (41 and 29%, respectively; PR 95% CI 1.29–1.54; 1.17–1.42). Physicians holding surgery specialties were 85% and 67% more prevalent among dual and private practitioners as compared to the public practitioners, respectively (PR 95% CI 1.38–2.46; 1.21–2.29). These differences became more evident across the categories when surgery and general clinical specialties were considered (146% and 91% more prevalent among dual and private practitioners rather than public practitioners – PR 95% CI 1.85–3.27%; 1.40–2.61).
More than half of the physicians surveyed (55.5%; 95% CI 51.0%–60.0%) reported wages ranging from US$ 3857.00 to US$8969.00. Lower incomes (below US$ 3857.00) were reported by 20% of the interviewees (95% CI 18.4%–21.7%), whereas the highest income values (more than US$8969.00) were reported by 20.7% of physicians (95% CI 18.3%–23.1%).
Distribution of physician’s income across the sectors revealed marked differences between the categories; physicians earning less than US$ 3857.00 were 226,8% (PR 95% CI 0.25–0.37) and 73,6% (PR 95% CI 0.48–0.69) more prevalent among public practitioners in relation to dual and private practice physicians, respectively. Contrastingly, physicians with monthly wages ranging from US$8969.00 to US$10,762.00 were 116 and 108% more prevalent among dual and private practitioners, respectively, as compared to public practice physicians (PR 95% CI 1.35–3.45 and 1.26–3.44). The same distortions were intensified among physicians earning more than US$10,762.00: professionals who fell into this category were 661 and 807% more prevalent among dual and private practitioners, respectively, in relation to physicians providing public medical services (PR 95% CI 3.72–11.73; 4.51–14.44).