Evolution of Infant Mortality in Ecuador: A Spatial Analysis From 2010 to 2019

15 The health situation of children is fundamental for the big picture of public health in a country. 16 Particularly, the death of children under one year of age, calculated through the infant 17 mortality rate is still a key indicator, especially in Latin America where the overall rate has 18 been constantly decreasing down to 13.9 infant deaths per 1000 live births. But this global 19 figure encompasses geographical and temporal disparities within the same country. This is 20 why it is interesting to analyze this evolution through a geomatic method of spatial 21 prioritization. By combining hotspots detection (Local Indicators of Spatial Association, LISA) 22 and time trend over 20 years (Mann-Kendall) at municipal level data from Ecuador, a country with infant mortality similar to the regional average, we obtain the most critical townships that should receive special attention with respect to maternal and infant health.

and time trend over 20 years (Mann-Kendall) at municipal level data from Ecuador, a country 23 with infant mortality similar to the regional average, we obtain the most critical townships that 24 should receive special attention with respect to maternal and infant health.  All around the world, statistic measures of mortality are used to evaluate the health state of a 31 population [1] and consequently reflect the socio-economic development, general conditions 32 of life and social wellbeing of a country [2]. Among these measures, the infant mortality rate 33 (IMR) is one of the indicator most used in health [3] and is defined as the likelihood of a live 34 birth to die before the age of one [4].

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In Latin America and the Caribbean, progress in child survival has been remarkable, starting

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There are studies that have focused on understanding infant mortality from a spatial [10] and 46 temporal [11]

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This study proposes an analysis of the spatial and temporal variations of infant mortality (IM) 54 in Ecuador at the municipality level and seeks out those areas where there are significant 55 groupings below or above the national average. This could help to prioritize sectors where 56 greater accessibility and availability of child health care services are needed. In order to p. 3 / 13 prioritize areas of action, it is of interest to identify the municipalities in which the highest rates 58 are found and in which the trend is strongly increasing.

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No studies have been found in Ecuador where spatial analysis is used for infant mortality,

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The Mann-Kendall non-parametric statistical test is used to determine the time trend over a 80 period of the annualized IMR. To apply this test, the data do not need to fit any particular 81 distribution [20]. The statistic makes combinations of each pair of observed values, over time, 82 that is, it checks whether IMR j > IMR i or IMR j < IMR i and counts the number of pairs that 83 increase or decrease over time (it is the relative frequency of increases minus the relative 84 frequency of decreases), it is calculated for each spatial unit as [21]: where the sign function is given by

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Given i and j in {1,2,…,n}, the index is defined by: where n is the total of municipalities, x i the IMR in municipality i, x j the IMR in another 113 municipality j, ̅ the average of the IMR and w i,j the elements of the contiguity matrix W that 114 links municipality i to j.

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As there are spatial effects such as heterogeneity that refer to the indistinct behavior of the  In this case, the methodology was designed according to logical criteria. First, in order to 131 eliminate inconsistent rates, municipalities with less than 2 deaths were excluded. The 132 counties with higher IMR during the most recent year were selected, using the 90% percentile 133 threshold. The frequency, in number of year, of pertaining to a high-high or hotspot cluster is 134 used to give priority. The third factor considered is the higher positive trend over all the period 135 studied.

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Eventually the hotspot repetition over years can be more strictly evaluated using the logical 137 AND operator instead of the OR operator ( Figure 1).

Results 141
Since 2000, the national IMR has been steadily decreasing, but as of 2014, the rate has 142 begun to grow again which is of great concern (Figure 2).           Eight municipalities were identified as a priority (Table 1), where policies could be 188 implemented to improve the socioeconomic conditions of the population, infrastructure, 189 coverage and accessibility to health services, or even improve the registration of deaths and 190 births, among other strategies that could potentially help reduce the high IMR and reverse the 191 trend. While there are many more municipalities with high IMR, these eight municipalities are 192 of more concern as they have higher IMR values, the trend is increasing over the years, and 193 they generate statistically significant spatial clusters. It is most appropriate that the IMR is

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Another important point in this study is that the highest infant mortality rates are in the most 205 important urban areas of the country (Quito, Guayaquil and Cuenca) and the trend in these 206 areas is increasing, despite the fact that sanitary conditions and medical assistance are much 207 better than in rural areas; however, it should be taken into account that the information 208 considered was analyzed by municipality of death, so it would also be important to apply it to 209 municipality of residence in order to identify the main focus of risk; secondly, birth and death 210 data should be better recorded in cities than in rural areas, which suggests that there could be 211 an underestimation of the information in areas away from urban centers.

Conclusions 214
The application of spatial analysis methods in public health, allowed to analyze the temporal 215 and spatial trend of infant mortality rates in continental Ecuador, the findings of this research