Correlational analysis
Scatterplots (diagrams 3 to 11 in Figure 3) suggested that income represented by the per capita RGDP (diagram 3), BFP coverage rate (diagram 4) and educational attainment (diagram 5) were inversely correlated with the IMR. It is worth mentioning that the scatterplot suggests that the is correlation between IMR and income might be nonlinear and that as income increases it may have different impacts on IMR, probably more intensively on lower-income households.
Although presenting greater dispersion, the employment rate (diagram 6), the number of physicians and nurses per thousand inhabitants (diagram 8), and sewage service coverage (diagram 11) also seem to be inversely correlated with IMR. Conversely, the fertility rate (diagram 9) was positively and strongly correlated with IMR. Highly dispersed, a possible correlation between infant IMR and the number of livebirths by prenatal visits (diagram 7) and coverage rate of water supply (diagram 10) seem unlikely.
The correlation matrix (Figure 4) suggested that IMR was negatively correlated with income (-0.67), fertility rate (0.74) and educational attainment (-0.65) and BFP coverage rate (-0.56), and positively and strongly correlated with fertility rate (0.74). Employment (-0.32), sewage service coverage rate (-0.41) and the number of physicians and nurses per 1000 inhabitants (-0.49) were weakly correlated with IMR. The number of livebirths by prenatal visits (-0.18) and water supply coverage rate (-0.24) seem not to be correlated with IMR.
Descriptive analysis
Tables 1, 2, 3, and 4 display the descriptive statistics of infant mortality rate (Table 1) and its structural determinants: income, BFP coverage rate (as result of social policies) (Table 1), educational attainment, and employment rate (Table 2), and the intermediate determinants: number of livebirths by the number of prenatal visits, the number of physicians and nurses per 1000 inhabitants (both related to the health system), fertility rate (Table 3) and safe water supply and sewage services coverage rates (Table 4), according to the macro-regions.
Structural determinants of infant mortality in Brazil 2004-2015
Except for the employment and coverage rates of the BFP (Table 1), the disparities observed in the structural determinants of infant mortality of the North and Northeast macro-regions are noteworthy. As shown in the correlational analysis, results suggested a strong negative correlation between per capita income (Table 1) and infant mortality, corroborated by much lower per capita income levels observed in the North macro-region (R$ 11,963) and Northeast macro-region (R$ 8,805), both presenting the highest infant mortality rates (17.63 and 16.84, respectively). In the opposite direction, the South and Southeast macro-regions presented the highest per capita income and the lowest infant mortality rates. Although the Southeast macro-region recorded the highest average per capita income (R$22,845) and only the second-lowest average IMR in the period (13.96 deaths per thousand livebirths), conversely, the South macro-region recorded the second-highest per capita income (R$20,794) and the lowest IMR (12.09 deaths per thousand livebirths). Regarding social policies, the different results of a possible association between BFP coverage (Table 1) and infant mortality rate draw attention, since the Southeast macro-region presented the second-lowest IMR and a low coverage rate of BFP (48.96%) in relation to the other macro-regions, whereas the South macro-region presented the second-highest average coverage rate of BFP (56.67%). The highest average coverage rate of BFP was observed in the Northeast macro-region (60.24%), whereas the North macro-region recorded the third average coverage rate (51.10%).
Table 1 Infant mortality rate and structural determinants: per capita income (per capita RGDP) and Bolsa Família Program coverage rate
|
Infant Mortality Rate*
|
Income (Per capita RGDP)**
|
BFP coverage rate***
|
|
Mean SD CI
|
Mean SD CI
|
Mean SD CI
|
North
|
17.628 1.64 15.53 20
|
11,963 3,996 6,429 16,665
|
51.10 23.18 6.74 71.85
|
Northeast
|
16.844 2.394 13.95 21.23
|
8,805 3,169 4,577 13,734
|
60.24 21.96 16.43 78.14
|
Southeast
|
13.958 1.247 12.39 15.86
|
22,845 7,414 12,329 32,707
|
48.96 21.81 7.77 70
|
South
|
12.097 1.377 10.32 14.77
|
20,794 7,379 11,491 32,297
|
56.67 20.43 17.52 74.89
|
Midwest
|
15.263 1.848 12.68 18.72
|
17,758 6,628 9,877 28,035
|
50.39 24.53 4.55 71.77
|
(*): Deaths by thousand live-births; (**): Values in Reals (Brazilian currency – R$) and (***): Percentage values
Table 2 Structural determinants: educational attainment and employment rate
|
Educational Attainment*
|
Employment rate*
|
|
Mean SD CI
|
Mean SD CI
|
North
|
46.24 5.53 34.7 52.85
|
92.42 0.669 91 93
|
Northeast
|
45.59 5.92 32.98 49.69
|
91.75 0.866 90 93
|
Southeast
|
56.29 2.72 52.71 59.46
|
91.58 1.676 89 94
|
South
|
58.76 2.35 55.47 63.41
|
94.83 1.029 93 96
|
Midwest
|
51.97 6.61 41.53 59.59
|
93.5 1.382 91 96
|
(*): Percentage values
The highest educational performance (Table 2) in terms of net enrollments in the secondary school by net enrollments in the primary school was also observed in the South macro-region (58.76%) and the second in the Southeast (56.29%). In contrast, a poor educational performance was observed in the North macro-region (46.24%) and Northeast macro-region (45.59%). Finally, the South macro-region also holds the highest average employment rate (Table 2) of the series (94.83), while the Midwest presented the second-highest (93.5%) while the Southeast macro-region presented the lowest (91.58%).
Intermediary determinants of infant mortality in Brazil 2004-2015
Regarding intermediary determinants, there are large disparities among macro-regions as well. A higher quality of prenatal care, represented by the number of livebirths by the number of prenatal visits (table 3), and greater availability of physicians and nurses (Table 3) follow the same patterns of the structural determinants, suggesting an association with lower infant mortality rates. The South macro-region recorded the second-highest average values for the number of live births by prenatal visits (0.47) and for the number of physicians and nurses per thousand inhabitants (2.77), while the Southeast macro-region recorded the highest values (5.82 and 3.02 respectively). Fertility rate also presented disparities between subregions, with a higher average value in the North (2.47 live births per women aged 15 to 49 years) and Northeast (2.2 live births per women aged 15 to 49 years) than in the other macro-regions. In this aspect, the South macro-region showed the lowest fertility rate (1.79 live births per woman aged 15 to 49 years).
Table 3 Intermediary determinants: livebirths by prenatal visits; number of physicians and nurses by thousand inhabitants and fertility rate
|
Live births/prenatal*
|
Physicians and nurses/
1000 inhabitants*
|
Fertility Rate*
|
|
Mean SD CI
|
Mean SD CI
|
Mean SD CI
|
North
|
0.315 0.053 0.26 0.42
|
2.04 0.088 1.91 2.17
|
2.474 0.285 2.25 3.12
|
Northeast
|
0.228 0.032 0.2 0.31
|
1.925 0.104 1.76 2.09
|
2.204 0.227 1.9 2.59
|
Southeast
|
0.582 0.117 0.38 0.85
|
3.018 0.203 2.7 3.28
|
1.807 0.126 1.64 2.02
|
South
|
0.473 0.088 0.36 0.64
|
2.77 0.196 2.45 3.1
|
1.791 0.135 1.62 2.03
|
Midwest
|
0.312 0.497 0.25 0.4
|
2.317 0.146 2.05 2.54
|
2.024 0.14 1.83 2.26
|
(*): Unit values
Table 4 Intermediary determinants: safe water supply and sewage service coverage rates
|
Water supply coverage*
|
Sewage service coverage*
|
|
Mean SD CI
|
Mean SD CI
|
North
|
95.25 3.441 8.9 101
|
14.75 4.751 5 23
|
Northeast
|
102.67 3.055 97 109
|
40.67 4.64 34 47
|
Southeast
|
110 3.045 104 114
|
95.92 6.33 87 105
|
South
|
113.75 3.467 107 118
|
41.58 9.2 28 58
|
Midwest
|
117.67 3.576 112 123
|
28.83 7.222 19 40
|
(*): Percentages values
The Midwest macro-region presented the highest safe water supply average coverage rate (Table 4), and, conversely, the lowest sewage service average coverage rate, and the third lower IMR (15.26 deaths per thousand livebirths). In this regard, the South macro-region recorded the second-highest average coverage rate of water supply, and although it recorded the second-highest sewage service average coverage rate (Table 4) (41.58%), it barely reached half of the sewage service average coverage rate of the Southeast macro-region (95.92%).
In summary, the South macro-region presented the lowest average IMR, recorded the highest educational attainment and employment rates, the second-highest per capita income, BFP coverage rate, quality of prenatal care, access to health professionals, water supply coverage rate and, particularly, the second-lowest sewage service coverage rate.
The evolution of infant mortality in Brazil and its determinants 2014-2015
Although our analysis so far suggested that there is a correlation between IMR and income, fertility rate, education, employment, BFP, and sewage services coverage rate and that there are many disparities regarding the indicators of social determinants of infant mortality in Brazil at the structural and intermediary levels, one must analyze the evolution of these factors over time to verify if these disparities are persistent and how they may impact IMR. In graphs 1 to 10 (Figure 5), we analyzed the evolution of each of these factors regarding the indicator of interest, the infant mortality rate between 2004 and 2015 according to the annual average values of indicators of the macro-regions and the country as a whole.
Infant mortality rate
In Graph 1 we noted a downward trend in the infant mortality rate (IMR) over the entire period, with higher rates in the North and Northeast macro-regions. The Northeast macro-region presented the greatest downward trend in IMR (36%), although differences between this region and the North macro-region in relation to the others are still high, with much higher rates compared with to the national average. The IMR in the Southeast macro-region declined more slowly than the country's average rates (18.2% and 28.5% respectively). Infant mortality rates in the South macro-region are the lowest over the period and declines have remained above the national average (30%).
Structural determinants of infant mortality
Per capita Income (Per capita RGDP)
Graph 2 shows that income grew over the entire period, especially after 2009. The South, Southeast, and Midwest regions presented the highest averages of per capita income ( 227%, 162% and 213.5%), however, the Southeast macro-region presented an expressive decrease of per capita income between 2014 and 2015.
Bolsa Família Program
The coverage rates of BFP (Graph 3) presented the greatest growth between 2004 and 2009 in all macro-regions. After this period, the BFP coverage seems to grow at decreasing rates. The Northeast and the South macro-region recorded higher coverage rates in relation to the country’s average. Regarding the IMR, it should be mentioned that the Northeast macro-region presented the highest IMR at the beginning of the interval but also faster declines in relation to the others (Graph 1). The South macro-region also presented slightly higher BFP coverage rates in relation to the national average.
Educational attainment
For the educational attainment indicator, the South macro-region had the highest national average, all over the period (Graph 4). It is worth noting that such macro-region also recorded the lowest average IMR (Graph 1). The indicator of educational attainment in the Midwest macro-region, together with that of the Northeast macro-region, seems to have grown faster than the others, although, that indicator also suggests the existence of inequalities between the North and Northeast macro-regions in relation to the others.
Employment
What stands out in Graph 5 is a significant drop in the employment rate between 2014 and 2015, mainly in the Northeast (-2.93%) and Southeast (-3.67%) macro-regions, which reached the lowest employment levels at the end of the series (89.3%). Another result to be highlighted is that the South macro-region presented the highest employment average rate throughout the period.
Intermediary determinants of infant mortality
Quality and effectiveness of prenatal care
It should be noted that during the entire period, the number of live births by prenatal visits (Graph 6) in the South and Southeast macro-regions presented the higher coefficients, with the greatest increase observed in the Southeast macro-region between 2009 and 2011 (18%). On the other hand, the Northeast macro-region presented the poorest performance in terms of prenatal care over the period and the lowest availability of health professionals over the interval (Graph 7).
Availability of healthcare professionals
The North and Northeast macro-regions counted with a low proportion of physicians and nurses per thousand inhabitants in relation to the others (Graph 7). The Southeast and South macro-region recorded a higher availability of physicians and nurses over the period, which also suggests the existence of inequalities in terms of effectiveness and availability of health services between macro-regions with implications to the performance of prenatal care.
Fertility rate
Graph 8 showed a steady declining trend of fertility rate over the entire period in all macro-regions. Exceptionally, the curves of the South and Southeast macro-regions in Graph 8 perfectly overlapped each other and were the ones showing the lowest fertility rates during the period. The Northeast macro-region presented the greatest decline in fertility rates between 2004 and 2015 (-28.6%), converging to the national average (1.85 live births per women aged 15 to 49 years). Although the North macro-region also demonstrated important declines in fertility rate, it remained far higher in relation to the national average (2.25 live births per women aged 15 to 49 years).
Access to safe water supply and sewage services
Regarding the access to safe water (Graph 9), there were almost imperceptible increases only in the South, Southeast, and Midwest macro-region between 2013 and 2015. Those macro-regions also presented higher levels of water supply coverage rates in relation to the national average. In the North and Northeast macro-regions, some oscillation were observed, with the coverage rates in 2015 remaining practically at the same levels as in 2004. All series seem to be stationary which may explain the huge dispersion observed in the scatterplot’s diagrams and the weak probability of correlation to IMR.
On the other hand, in Graph 10, results suggest that access to sewage services probably acts differently, with different impacts depending on the socioeconomic context. The South macro-region showed an average coverage rate of sewage service that barely reached half of that observed in the Southeast macro-region (41.6% and 95.9%, respectively). It is noteworthy that although both macro-regions had higher average income, employment and educational achievement, lower fertility rate and greater access and quality health services, the Southeast had the highest average coverage of sewage services.