Relationship between individual socioeconomic variables and the prevalence of different procedures.

**Strong correlation, Pearson's correlation coefficient.A correlation matrix was established for various procedures (column 1) and socioeconomic factors (columns 2–4). A Pearson's correlation coefficient was established for each relationship. A negative value indicates a negative correlation. Value ranges of 0–0.09, 0.1–0.3, 0.31–0.5, and 0.51–1.0 were considered to have no, small, medium, and strong correlations, respectively. CABG and PTCA had a strong negative correlation with both education and income.Socioeconomic Factors Key.Employment = unemployed for greater than one year.Education = having more than a high school education.Income = household income greater than $ 50,000 USD.