There are still major socioeconomic differences in health, and the relative differences are continuing to increase.
Nevertheless, modern epidemiologists rarely consider socioeconomic factors and the population perspective, except perhaps to occasionally adjust for social class in analyses of the health effects of tobacco smoke, diet, and other lifestyle factors in individuals. For example, studies in most industrialized countries have repeatedly found strong associations between social class and cancer, yet social class did not feature, except for a brief mention as a confounder, in the most comprehensive review of the causes of cancer in the United States, and one leading epidemiology text states that "social class is presumably related causally to few if any diseases.