Correlation of sex ratio at birth with health and socioeconomic indicators.

INTRODUCTION

The sex ratio at birth (male divided by total live births: M/T) has been mooted as a potential sentinel health indicator. Several metrics indicate individual countries' health and socioeconomic status. In this study, in all available countries (where such data was accessible), M/T and these indicators were compared in order to ascertain whether better (vis-à-vis health and socioeconomic status) levels of these indicators were associated with higher M/T in available countries.

METHODS

The following were obtained (by country) from various sources: M/T, infant mortality rate, under 5 years mortality rate, fertility rate, Human Development Index, gross domestic product per capita, life expectancy for both sexes, females, males, as well as both sexes Health Adjusted Life Expectancy (HALE). Pearson correlation was performed comparing M/T and these indicators.

RESULTS

Despite weak correlation values, all except for the Human Development Index (HDI) correlated with M/T at statistically significant levels.

DISCUSSION

A decrease in mortality and an increase in life expectancy and GDP/capita are indicators of socioeconomic wellbeing. In this study, mortality was negatively correlated with M/T. Life expectancy and GDP/capita were both positively correlated with M/T, indicating that M/T may also serve as a surrogate health indicator, and incidentally, also supporting the Trivers-Willard hypothesis. Improving economies lead to increasing education, which in turns tends to lower fertility rate in association with a declining M/T. In conclusion, the global correlation of health and socioeconomic indicators with M/T suggests that M/T may be a useful sentinel health indicator.