However, the GHS Index also incorporates social, political, technical and environmental determinants of health security, which do not necessarily correlate directly with national income level alone. On measures of healthcare access (Indicator 4.3), for example, the first-ranking, second-ranking and fifth-ranking countries were Thailand (upper-middle-income), Georgia (lower-middle-income) and Nigeria (lower-middle-income), respectively. Other factors, such as strength of laboratory systems (Indicator 2.1) and international commitments (Indicator 5.3), also correlate more strongly with overall GHS Index scores (r=0.80 and 0.76, respectively) than with overall GDP (r=0.25 and 0.23, respectively). To further prevent potential confounding by income level, users might consider comparing overall, indicator and sub-indicator-level scores across countries within a given income group and adjusting model weights to align more closely with the specific health priorities of a given country or region.