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Directly
Age Standardised Rates
This
is an example calculation of directly standardised mortality rates from Coronary
heart disease in persons aged under 65. It is taken from Department of Health,
Compendium of Clinical Indicators 2000
(NHS
only). A
template for calculating directly standardised rates is available on an excel
spreadsheet.
Step
1: Calculation of age-specific death rates per 100,000
population in area a:
(a)
Number of deaths by age group in area a
|
Year
|
Under
1
|
1-4
|
5-9
|
10-14
|
......
|
55-59
|
60-64
|
|
1988
|
0
|
1
|
1
|
0
|
......
|
6,628
|
11,842
|
|
1989
|
2
|
4
|
1
|
0
|
......
|
6,087
|
10,959
|
|
1990
|
6
|
4
|
1
|
0
|
......
|
5,807
|
10,470
|
|
1991
|
4
|
0
|
0
|
2
|
......
|
5,417
|
9,949
|
(b)
Population by age-group (100,000s) in area a*
|
Year
|
Under
1
|
1-4
|
5-9
|
10-14
|
......
|
55-59
|
60-64
|
|
1988
|
6.47
|
24.54
|
29.83
|
27.84
|
......
|
24.99
|
24.49
|
|
1989
|
6.42
|
25.15
|
29.95
|
27.79
|
......
|
24.66
|
24.23
|
|
1990
|
6.48
|
25.42
|
30.11
|
28.18
|
......
|
24.43
|
24.10
|
|
1991
|
6.63
|
25.75
|
30.36
|
28.76
|
......
|
24.31
|
23.98
|
*
For ease of presentation numbers are truncated to the nearest thousand.
(c)
Age-specific death rates per 100,000 in each age-group/year = number of
deaths divided by population (in 100,000s)
|
Year
|
Under
1
|
1-4
|
5-9
|
10-14
|
......
|
55-59
|
60-64
|
|
1988
|
0
|
0.04
|
0.03
|
0
|
......
|
265.24
|
483.62
|
|
1989
|
0.31
|
0.16
|
0.03
|
0
|
......
|
246.84
|
452.33
|
|
1990
|
0.93
|
0.16
|
0.03
|
0
|
......
|
237.72
|
434.41
|
|
1991
|
0.60
|
0
|
0
|
0.07
|
......
|
222.81
|
414.87
|
Step 2: Calculation of
European age-standardised annual rates:
Multiply
the death rate for area a of age group/year by the European
Standard Population of age group and then sum these "expected"
numbers of deaths.
|
Year
|
<1
|
1-4
|
5-9
|
10-14
|
......
|
55-59
|
60-64
|
Sum
of ages
Under
65
|
Standard
Rates*
|
|
1988
|
0
|
261
|
235
|
0
|
......
|
1,591,457
|
2,418,097
|
5,812,752
|
65.31
|
|
1989
|
499
|
1,018
|
234
|
0
|
......
|
1,481,022
|
2,261,639
|
5,416,823
|
60.86
|
|
1990
|
1,482
|
1,007
|
232
|
0
|
......
|
1,426,291
|
2,172,052
|
5,205,524
|
58.49
|
|
1991
|
966
|
0
|
0
|
487
|
......
|
1,336,865
|
2,074,335
|
4,931,514
|
55.41
|
*
Obtained by dividing the sum of expected numbers at ages under 65 by the European
Standard Population at ages under 65 (89,000).
Step 3: For Calculation of average rate for 3
years, add the annual rates for 3 years and divide by 3.
| Year
|
Standardised
rate
|
| 1989
|
60.86
|
| 1990
|
58.49
|
| 1991
|
55.41
|
| 1989-91
|
58.25
|
The
European Standard Population
The European
Standard Population is used to compute the directly age-standardised rates.
The same population is used for males, females and all persons.
|
Age
group
|
European
Standard Population
|
|
0
|
1,600
|
|
1-4
|
6,400
|
|
5-9
|
7,000
|
|
10-14
|
7,000
|
|
15-19
|
7,000
|
|
20-24
|
7,000
|
|
25-29
|
7,000
|
|
30-34
|
7,000
|
|
35-39
|
7,000
|
|
40-44
|
7,000
|
|
45-49
|
7,000
|
|
50-54
|
7,000
|
|
55-59
|
6,000
|
|
60-64
|
5,000
|
|
65-69
|
4,000
|
|
70-74
|
3,000
|
|
75-79
|
2,000
|
|
80-84
|
1,000
|
|
85+
|
1,000
|
|
Total
|
100,000
|
Source: 1991 World
Health Annual of Statistics - based on J Waterhouse et al (eds).
Cancer Incidence in Five Continents, Lyon, IARC, 1976 (Vol. 3,
page 456).
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