• COVID-19
• epidemiological methods
• public health
• statistics

Khalatbari-Soltani et al1 emphasised the need to complement WHO standard COVID-19 case reports with measures of socioeconomic position (SEP) factors of infected individuals. Their argument develops the idea that WHO’s clinical report is concentrated on age, gender, locations of diagnosis and residency, whereas additional factors of the social environment such as occupation, income or education might preventively uncover high-risk SEP disadvantaged individuals and populations. The importance of ‘non-medical’ data becoming ‘clinical’ predictors is extensively reviewed in the literature.2

Although currently infeasible to palliate backwards such data deficiencies at an individual level, this critical information gap might be indirectly approached through country-sensitive aggregated socioeconomic indexes as independent variables predicting cumulative COVID-19 official statistics (eg, total cases or total deaths per million). The yearly published aggregated Human Development Index (HDI) fits the needs of this …