The Social Institutions and Gender Index (SIGI) covers four dimensions, spanning major socio-economic areas that affect the entire lifetimes of women and girls ():

Using empirical econometric methods combined with the results from the SIGI, the Organisation for Economic Co-operation and Development (OECD) Development Centre explored the economic cost associated with gender-based discrimination. To analyse the relationship between gender-based discrimination in social institutions and income, the research uses different estimators – ordinary least squares (OLS) and two-stage least squares (2SLS) – and specifications. All resulting regressions have a high explanatory power and suggest a strong, negative and significant relationship between SIGI scores and income per capita in all specifications: higher levels of gender-based discrimination in social institutions are associated with lower levels of income per capita. The results are robust to the inclusion of additional controls, including gender gaps in outcomes. This means that the measurement obtained is the net effect of gender discrimination in social institutions on income, filtered from the effect of gender inequality in outcomes (Ferrant and Kolev, 2016[2]).