Age-adjusted Rates on IBIS Query System (Directly Age-adjusted)
Age Adjustment Weights (Updated January, 2012)
The age-specific rates for each age group in the study population are multiplied by the proportion of people in the same age group in the standard population distribution. The sum of these products is the age-adjusted, or age-standardized rate. The age-adjusted rate can be considered an average of each of the individual age-specific rates, but rather than being a simple average, it is a weighted average with each age-specific rate weighted by the proportion of people in that age group in the U.S. 2000 standard population.Age-adjusted rates control for age effects, allowing better comparability of rates across areas. Age-adjustment may also be used to control for age effects when comparing across several years of data, as the age distribution of the population changes over time. Only rates adjusted to the same standard population can be compared. Age adjustment is not appropriate if the age-specific death rates in the population of interest do not have a consistent relationship. The age-adjusted rate is hypothetical, and is useful only for comparing populations, either over time, by geographic area, by sex, or by racial/ethnic subgroups. For more information, see "Health Event Counts and Crude, Age-specific, and Age-adjusted Rates" Help
For more information on age adjustment using the 2000 projected U.S. population, see http://www.cdc.gov/nchs/data/statnt/statnt20.pdf
All weights used on IBIS are from the master list of 2000 U.S. projected and age-adjustedment weights.
U.S. 2000 Standard Population 11 Age Groups Weights (Used by Mortality, Hospital Discharge, ED Encounter, ED Primary Care Sensitive Conditions and UHAS* IBIS Query Modules)
Age Group | U.S. 2000 Population Projection (in thousands) |
Weight | |
---|---|---|---|
1 |
Under 1 Year | 3,795 |
0.013818 |
2 |
1 - 4 Years | 15,192 |
0.055317 |
3 |
5 - 14 Years | 39,977 |
0.145565 |
4 |
15 - 24 Years | 38,077 |
0.138646 |
5 |
25 - 34 Years | 37,233 |
0.135573 |
6 |
35 - 44 Years | 44,659 |
0.162613 |
7 |
45 - 54 Years | 37,030 |
0.134834 |
8 |
55 - 64 Years | 23,961 |
0.087247 |
9 |
65 - 74 Years | 18,136 |
0.066037 |
10 |
75 - 84 Years | 12,315 |
0.044842 |
11 |
85 Years and Over | 4,259 |
0.015508 |
Total, All ages | 274,634 |
1 |
Weight=Age-specific Population/Total population in All Age groups
*UHAS normalizes the weights when (1) age restriction has applied to the survey questions. (2) certain age groups have no observations.
U.S. 2000 Standard Population 10 Age Groups Weights (Used by Cancer Registry IBIS Query Modules)
Age Group | U.S. 2000 Population Projection (in thousands, from #1) |
Weight | |
---|---|---|---|
1 |
0 - 4 Years | 18,987 |
0.069135 |
2 |
5 - 14 Years | 39,977 |
0.145565 |
3 |
15 - 24 Years | 38,077 |
0.138646 |
4 |
25 - 34 Years | 37,233 |
0.135573 |
5 |
35 - 44 Years | 44,659 |
0.162613 |
6 |
45 - 54 Years | 37,030 |
0.134834 |
7 |
55 - 64 Years | 23,961 |
0.087247 |
8 |
65 - 74 Years | 18,136 |
0.066037 |
9 |
75 - 84 Years | 12,315 |
0.044842 |
10 |
85 Years and Over | 4,259 |
0.015508 |
Total, All ages | 274,634 |
1 |
Weight=Age-specific Population/Total population in All Age groups
U.S. 2000 Standard Population 8 Age Groups Weights (Used by BRFSS* IBIS Query Modules)
Age Group | U.S. 2000 Population Projection (in thousands) |
Weight | |
---|---|---|---|
1 |
18 - 24 Years | 26,258 |
0.1288 |
2 |
25 - 34 Years | 37,233 |
0.1827 |
3 |
35 - 44 Years | 44,659 |
0.2191 |
4 |
45 - 54 Years | 37,030 |
0.1817 |
5 |
55 - 64 Years | 23,961 |
0.1175 |
6 |
65 - 74 Years | 18,136 |
0.0889 |
7 |
75 - 84 Years | 12,315 |
0.0604 |
8 |
85 Years and Over | 4,259 |
0.0209 |
Total, 18 years and older | 203,851 |
1 |
Weight=Age-specific Population/Total population in All Age groups
*BRFSS normalizes the weights when certain age groups have no observations.
U.S. 2000 Standard Population 3 Age Groups Weights (Used by BRFSS IBIS Query Modules Including Race)
Age Group | U.S. 2000 Population Projection (in thousands) |
Weight | |
---|---|---|---|
1 |
18 - 34 Years | 63,491 |
0.3115 |
2 |
35 - 49 Years | 64,465 |
0.3162 |
3 |
50+ Years | 75,895 |
0.3723 |
Total | 203,851 |
1 |
Weight=Age-specific Population/Total population in All Age groups
*BRFSS normalizes the weights when certain age groups have no observations.
U.S. 2000 Standard Population 3 Age Groups Weights (Used by Mortality IBIS Query Modules Including Race)
Age Group | U.S. 2000 Population Projection (in thousands) |
Weight | |
---|---|---|---|
1 |
0 - 44 Years | 178,933 |
0.651532 |
2 |
45 - 65 Years | 60,991 |
0.22.2081 |
3 |
65+ Years | 30,710 |
0.126387 |
Total, All ages | 274,634 |
1 |