A new Inequity-in-Health Index based on Millennium Development Goals: methodology and validation

Developing a new Inequity-in-Health Index (IHI) assuming inequity as "inequality of health outcomes," based on Millennium Development Goals (MDG).

Ecological study. Countries from around the world were included from United Nations, the World Bank, and a nonprofit organization's databases. The reliability and validity of this bidimensional IHI was tested. Main factor analysis (promax rotation) and main component analysis were used.

Six variables were used for constructing the IHI was constructed with six variables: underweight children, child mortality, death from malaria in children aged 0-4, death from malaria at all ages, births attended by skilled health personnel, and immunization against measles. The IHI had high internal consistency (Cronbach's alpha=0.8504), was reliable (Spearman>0.9, P=0.0000), and had 0.3033pi around the world (range: 0pi-0.5984pi). IHI had high correlation with the human development and poverty indexes, health gap indicator, life expectancy at birth, probability of dying before 40 years of age, and Gini coefficients (Spearman>0.7, P=0.0000). IHI discriminated countries by income, region, indebtedness, and corruption level (Kruskal Wallis, P<0.01). IHI had sensitivity to change (P=0.0000).

IHI is a bidimensional, valid and reliable index to monitor MDG. A new reliable methodology for developing bidimensional indicators is shown, which could be used for constructing other ones with their corresponding scores and graphs.