DATA ELEMENTS AND DATA ELEMENT CONCEPTS
AGE
IDENTIFYING AND DEFINITIONAL ATTRIBUTES
Metadata type:
DERIVED DATA ELEMENT Version: 1
Definition:
The concept of Age describes how old a person is at a particular point in time in completed years. It is defined as the measure of the time elapsed from date of live birth to a specific point in time.
Context:
Age is one of the basic demographic variables used in population statistics. It is widely used in cross-classification with other variables such as sex, marital status, occupation etc.
RELATIONAL AND REPRESENTATIONAL ATTRIBUTES
Datatype:
Numeric
Field size:
Min: 1 Max: 3
Representational form:
Code
Representational layout:
N (NN)
Data domain:
Age is a flat classification containing one level with as many categories as needed for a particular collection or topic. Codes are provided to assist with data entry and/or output purposes.
The standard categories are single, complete, calendar years to 98, and a category for 99 and over.
0 0 years
1 1 year
2 2 years
.............
98 98 years
99 99 years and over
For the proposed criminal court collection output categories, refer to Guide for use.
Guide for use:
In addition to the above ABS standard classification, two extra values for 'Organisation' and 'Unknown/not stated' are necessary for the ABS criminal courts collection.
800 Not applicable (Organisation)
900 Unknown/Not stated
Age is measured by calculating the time elapsed (usually in complete years) between date of birth and a specific point in time.
For example, within the criminal courts collection, a defendant's Age could be calculated at Date of Finalisation by:
Age = (Date of Finalisation - Date of Birth) / 365.25
All years for a defendant's Age should be rounded down (e.g. A defendant aged 24 years and 10 months would be rounded down to 24 years).
For the purposes of the ABS criminal courts collection only, if the actual Date of Birth is not known or cannot be obtained, provision should be made to collect or estimate Age (in years).
Some suggested standard questions to use to collect Age in this instance are:
Age last birthday?
What was [your] [the person's] [(name)'s] age last birthday?
What is [your] [the person's] [(name)'s] age in complete years?
A Date of Birth can then be derived from this age using 0101 as DDMM if only the year is known. The actual or estimated year of birth should then be converted to an estimated date of birth according to the following convection: 0101YYYY, where YYYY is the estimated year of birth.
It is recommended that estimated Dates of Birth be identified by an appropriate date flag to prevent inappropriate use of Date of Birth data for record identification and/or the derivation of other data elements (such as Age) that require Date of Birth information.
The ABS recognises that it may not always be possible, for statistical or other reasons, such as legal age requirements, to adhere strictly to the output guidelines. It is particularly important, however, to ensure that as many categories as possible are multiples of 5 years, or capable of aggregation to such groupings, to facilitate maximum comparability of Age data from different sources.
Proposed output categories for use in a criminal courts collection (which includes juveniles) are:
10 years
11 years
12 years
13 years
14 years
15 years
16 years
17 years
18 years
19 years
20-24 years
25-29 years
30-34 years
35-39 years
40-44 years
45-49 years
50-54 years
55-64 years
65 years and over
Not applicable (for organisations)
Not specified (Unknown and not stated/inadequately described)
Verification rules:
Age needs to be such that the defendant is at or above the age of criminal liability (which is 10 years of age).
Collection methods:
Age can be derived from a single question in most collections.
The ideal question for most collections is:
What is [your] [the person's] [(name)'s] date of birth?
The recommended format for the collection of Age data using a self-enumerated questionnaire is:
Date of Birth: _ _ / _ _ / _ _ _ _
This provides the greatest amount of detail and can easily be converted to completed days, weeks, months and years as required. It also improves data quality and should be used wherever possible.
As Age is a derived data element it should not be stored within systems. What should be stored is the Date of Birth (Refer to Date of Birth data element) so that Age can be correctly derived. This also gives the greatest flexibility for derivation of new data items, cross-classification with other variables and in the production of output categories.
Related metadata:
Is derived from the data element:
Is a characteristic of the data element concept:
ADMINISTRATIVE ATTRIBUTES
Source document:
1. Standards for Social, Labour and Demographic Statistics (cat. no. 1200.0)
The ABS standards appear on the ABS web site. From the ABS home page (<www.abs.gov.au>) select: Methods, Classifications, Concepts & Standards/ABS concepts, classifications and statistical standards/12. Classifications and work manuals/1200.0 Standards for Social, Labour and Demographic Variables.
2. Juvenile Justice National Minimum Dataset Data Dictionary
Source organisation:
1. Australian Bureau of Statistics
2. Australian Institute of Health and Welfare
History:
Commenced 2005
Comments:
None