Fig. 1

Predicted probabilities of hypertension based on the regression models to assess the effect modification of individual-level education by area-level education. The p-value presented refers to the global interaction test. Education level: 1 = less than primary; 2 = primary; 3 = secondary; 4 = university or higher. Sub-city- and city-educational attainment score values are based on the standardized variable used in the model so the range of values differs from the one presented in Table 1