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SCAN Cancer Tables

Cancer Incidence Related Definitions and Associated Formulas
Statistical Terms
Demographic Information
Population Data
Sources of Information
Miscellaneous Information
Counties by Regions

This link shows formulas used to calculate rates with examples.


Mortality - The number of deaths, with a certain type of cancer as the underlying cause of death, during a specific time period (i.e. one year). Cancer mortality is usually expressed as the number of deaths due to cancer per 100,000 population.

Frequency - The number of deaths from a certain type of cancer during a specific time period.
Rate - The number of deaths from a certain type of cancer divided by the population of individuals in that geographic area (i.e. state, county) during a specific time.

Crude Rate - The number of deaths during a specific time period and in a specific geographic area per 100,000 individuals who are susceptible to dying.

Age-specific rate - The number of deaths from a certain type of cancer per 100,000 individuals over a specific time period for a specific age group.

Age-adjusted rate - Cancer rates vary with age, and populations vary by their age distributions. Age adjustment allows for comparison of rates between different populations with different age structure. The "effect of age" is no longer present upon age-adjustment. Age-adjusted rates are calculated using the age distribution of the 1970 or 2000 US standard population, and they are usually expressed per 100,000 population.

95% Confidence Intervals - The formulas used to calculate the 95% confidence intervals is R + 619.81*(R/D)1/2
Where R = crude cancer mortality rate, D = population denominator, and 619.81=1.96*(100,000)1/2
When frequencies are less than 100 then 95% confidence intervals are calculated using the formulas provided on pages 98-102 in the NCHS 2001 Birth Report a pdf document.

Rate Calculations With Small Numbers - There are variations in all statistics that are the result of chance. This characteristic is of particular importance in classifications with small numbers of events where small variations are proportionately large in relation to the base figure. As an example, small changes in the number of deaths in small population areas or in the number of deaths from a rare cancer could result in large changes in these crude rates. For this reason, rates for counties with small populations or other small bases should be used cautiously.


Race - Race is reported as White, Black, Other, and Unknown. Other race group includes Asian, Pacific Islander, and Native Americans.

Age - Age at death


Population Data - With the exception of population data by race and population data for selected age groups of teens, the 2000 Census data, provided by the Office of Research and Statistics (South Carolina Budget and Control Board), were used to calculate the rates in this report. Population data by race and for selected age groups were modified. Age Adjusted rates use 18 age groups and the corresponding 18 standard weights from the 1970 and 2000 U.S. population.

Population Data By Race - The U.S. Census Bureau Population data contains data for both "multiple race", and single race categories. This presents problems for calculating vital statistical rates. The following methodology was developed jointly by Office of Research and Statistics, South Carolina State Budget and Control Board and the Division of Biostatistics and Health GIS, Public Health Statistics and Information Services, SCDHEC.

The populations of these two race categories were allocated to the standard single race categories by age, gender and county. This allocation was based on the proportional distribution of the population of the standard single race categories within each of these age, gender, county groups.

Population Data For Selected Age Groups - For inter-census years, ORS provides estimated population data for South Carolina by age for five-year age groups. It is assumed that the population within each of these age categories is distributed uniformly through out the age interval. Based on this assumption, the population for females 14-17, 15-17 and 18-19 years is derived, consecutively, as follows - (20% of the female population 10-14 years plus 60% of the female population 15-19 years), (60% of the female population 15-19), and (40% of the female population 15-19).

Residence Data - Data allocated to the place in South Carolina where the person lived at time of death.


Centers for Disease Control (CDC) - Located in Atlanta, GA, the CDC is an agency of the Department of Health and Human Services. The CDC serves as the national focus for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of people of the United States.

National Program of Cancer Registries (NPCR) - Funded by the CDC, the NPCR is a population-based system of cancer registries established in 1992 by the Central Cancer Registries Amendment Act (Public Law 102-515). When fully implemented, programs funded by the NPCR will collect data on cancer for 96% of the US population.

Surveillance, Epidemiology and End Results (SEER) - Program of the National Cancer Institute that collects and publishes cancer incidence and survival data from 11 population-based cancer registries and three supplemental registries covering approximately 14 percent of the United States population.


Cancer site - The body organ or system where cancer originates; the anatomical site of origin.

Metastasis - Movement of disease from one organ or part to another not directly connected.

Risk factor - Anything that increases a person's chances of getting a disease. Examples include smoking, diet, and age.

Cancer cluster - A group of more cancer cases/deaths than normal in a small area, like a neighborhood, or within a short time period. Cancer clusters are reported when people learn that an unusual number of their friends, family, neighbors or co-workers have cancer.


Region 1 
01 Abbeville
04 Anderson
19 Edgefield
24 Greenwood
30 Laurens
33 McCormick
37 Oconee
41 Saluda

Region 2
11 Cherokee
23 Greenville
39 Pickens
42 Spartanburg
44 Union

Region 3
12 Chester
20 Fairfield
29 Lancaster
32 Lexington
36 Newberry
40 Richland
46 York

Region 4
13 Chesterfield
14 Claredon
16 Darlington
17 Dillon
21 Florence
28 Kershaw
31 Lee
34 Marion
35 Marlboro
43 Sumter

Region 5
02 Aiken
03 Allendale
05 Bamberg
06 Barnwell
09 Calhoune
38 Orangeburg

Region 6
22 Georgetown
26 Horry
45 Williamsburg

Region 7
08 Berkeley
10 Charleston
18 Dorchester

Region 8
07 Beaufort
15 Colleton
25 Hampton
27 Jasper

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