To interpret the Human Development Index (HDI) of North America, Central America, and the Caribbean accurately, the factor that must be considered is:
Canada and the U.S. have significantly higher scores than the rest of the countries.
This is important because the HDI is an average calculation; thus, the high scores from Canada and the U.S. can disproportionately influence the overall HDI of the region, potentially masking the lower HDI scores of other countries within the region, such as those in Central America and the Caribbean.