American Indian Culture and Research Journal

INTRODUCTION Few published data have addressed the descriptive epidemiology of cancer among various American Indian tribes nationwide, and risk factor information on a site-specific or tribal-specific basis is almost nonexistent in published reports. Nonetheless, with appropriately guided searches, a tenacious researcher of health care information can be directed to specific data sources on cancer among American Indians/Alaska Natives in various parts of the country. In this chapter, we will discuss some of these data sources, their access, and their limitations. METHODOLOGY A study of the descriptive epidemiology of cancer or any other disease generally starts with the calculation of incidence rates, which are based on the number of newly diagnosed cases in a defined population during a specified period of time, or mortality rates, which are based on the number of deaths during a specified period. Crude rates, obtained simply by dividing the number of cases (numerator) that occur during a specified period of time by the total population at risk (denominator), are seldom informative, because they do not take into account any variation in the distributions of ages in the different populations that one wants to compare. Indian groups in the United States tend to have young populations; crude rates for most tribes typically are very low, because the denominators are weighted with relatively large numbers of young persons who have not yet reached the ages at which cancers occur most frequently.