4530.0 - Crime Victimisation, Australia, 2018-19
Explanatory notes
Introduction
This publication presents results from the Crime
Victimisation Survey, a topic on the Multipurpose Household
Survey (MPHS) conducted throughout Australia from July 2018
to June 2019. The MPHS, undertaken each financial year by
the Australian Bureau of Statistics (ABS), is a supplement
to the monthly Labour Force Survey (LFS) and is designed to
collect statistics for a number of small, self-contained
topics.
This publication -
* covers the
Crime Victimisation topic; and
* presents
details about the prevalence of a selected range of
personal and household crimes,
* including the
socio-demographic characteristics of persons experiencing
the selected crimes,
* experiences of repeat victimisation,
and
*
the characteristics of the most recent incident of each
crime type experienced.
Some estimates from previous
iterations of the Crime Victimisation Survey are also
included in this publication.
The Crime Victimisation Survey is being conducted again as
part of the MPHS for the reference period 2019-20, with
results expected to be released in early 2021.
Scope and coverage
The scope of the Crime Victimisation Survey was restricted
to people aged 15 years and over who were usual residents of
private dwellings and excludes:
- members of the Australian permanent defence forces;
- certain diplomatic personnel of overseas
governments, customarily excluded from Census and
estimated resident population counts;
- overseas residents in Australia; and
- members of non-Australian defence forces (and their
dependants).
Additionally, the 2018-19 MPHS scope
excluded:
- persons living in non-private dwellings such as
hotels, university residences, boarding schools,
hospitals, nursing homes, homes for people living with
disabilities, and prisons; and
- persons resident in the Indigenous Community Strata
(ICS).
The scope for MPHS included households residing in urban,
rural, remote and very remote parts of Australia, except the
ICS. In the LFS, rules are applied which aim to ensure that
each person in coverage is associated with only one
dwelling, and hence has only one chance of selection in the
survey. See
Labour Force, Australia (cat. no. 6202.0) for more
detail.
Data collection
The Crime Victimisation Survey is one of a number of small,
self-contained topics on the Multipurpose Household Survey (MPHS),
conducted throughout Australia from July 2018 to June 2019.
The MPHS is a supplement to the monthly LFS. In 2018–19, the
MPHS topics were:
- Crime Victimisation;
- Patient Experiences in Australia;
- Barriers and Incentives to Labour Force
Participation;
- Retirement and Retirement Intentions;
- Qualifications and Work; and
- Income (Personal, Partner's, Household).
For all topics, general demographic information such as age,
sex, labour force characteristics, education and income are
also available.
ABS interviewers conducted personal interviews during the
2018-19 financial year for the monthly LFS. Each month, one
eighth of the dwellings in the LFS sample were rotated out
of the survey and selected for the MPHS. After the LFS had
been fully completed for each person in scope and coverage,
a usual resident aged 15 years or over was selected at
random (based on a computer algorithm) and asked the
additional MPHS questions.
In the MPHS, if the randomly selected person was aged 15 to
17 years, permission was sought from a parent or guardian
before conducting the interview. If permission was not
given, the parent or guardian was asked the questions on
behalf of the 15 to 17 year old (proxy interview). Questions
relating to sexual assault and the involvement of alcohol or
substances in the most recent incident of physical assault
and face-to-face threatened assault were not asked of proxy
respondents. Only persons aged 18 years and over were asked
questions on sexual assault and the involvement of alcohol
or substances in the most recent incident of physical
assault and face-to-face threatened assault.
Data were collected using Computer Assisted Interviewing (CAI),
whereby responses were recorded directly onto an electronic
questionnaire in a notebook computer, with interviews
conducted either face-to-face or over the telephone. The
majority of interviews were conducted over the telephone.
Sample size
After taking into account sample loss, the response rate for
the Crime Victimisation Survey
was 71.8%. In total,
information was collected from 28,719 fully responding
persons. This includes 477 proxy interviews for people aged
15 to 17 years, where permission was not given by a parent
or guardian for a personal interview.
Weighting
Weighting is the process of adjusting results from a sample
survey to infer results for the total in-scope population.
To do this, a 'weight' is allocated to each enumerated
person. The weight is a value which indicates the number of
persons in the population represented by the sample person.
The first step in calculating weights for each unit is to
assign an initial weight, which is the inverse of the
probability of being selected in the survey. For example, if
the probability of a person being selected in the survey was
1 in 600, then the person would have an initial weight of
600 (that is, they represent 600 people).
Benchmarks
The initial weights were calibrated to align with
independent estimates of the population of interest,
referred to as 'benchmarks'. Weights calibrated against
population benchmarks ensure that the survey estimates
conform to the independently estimated distribution of the
population rather than the distribution within the sample
itself. Calibration to population benchmarks helps to
compensate for over-or-under-enumeration of particular
categories of persons/households which may occur due to
either the random nature of sampling or non-response.
For household estimates, the MPHS was benchmarked to
independently calculated estimates of the total number of
households in Australia. The MPHS estimates do not (and are
not intended to) match estimates for the total Australian
person/household populations obtained from other sources.
The survey was benchmarked to the Estimated Resident
Population (ERP) living in private dwellings in each state
and territory at December 2018, based on the 2016 Census.
People living in Indigenous communities were excluded.
While the LFS benchmarks are revised every five years to
take into account the outcome of the five-yearly rebasing of
the ERP following the latest Census, the supplementary
surveys and MPHS (from which the statistics in this
publication are taken) are not.
Small differences will
therefore exist between the civilian population aged 15
years and over reflected in the LFS and other labour
household survey estimates, as well as over time.
Estimation
Survey estimates of counts of persons are obtained by
summing the weights of persons with the characteristic of
interest.
Confidentiality
To minimise the risk of identifying individuals in aggregate
statistics, a technique called perturbation is used to
randomly adjust cell values. Perturbation involves a small
random adjustment of the statistics and is considered the
most satisfactory technique for avoiding the release of
identifiable statistics while maximising the range of
information that can be released. These adjustments have a
negligible impact on the underlying pattern of the
statistics.
After perturbation, a given published cell value will be
consistent across all tables. However, adding up cell values
to derive a total will not necessarily give the same result
as published totals.
Perturbation has been applied to Crime Victimisation Survey
datasets since 2013–14. Data from previous cycles (2008-09
to 2012–13) have not been perturbed, but underwent a
different confidentialisation method to protect the
confidentiality of respondents.
Reliability of estimates
All sample surveys are subject to error which can be broadly
categorised as either sampling error or non-sampling error.
Sampling error is the difference between the published
estimates, derived from a sample of persons, and the value
that would have been produced if the total population (as
defined by the scope of the survey) had been included in the
survey.
Non-sampling error may occur in any statistical collection,
whether it is based on a sample or a full count such as a
census. Sources of non-sampling error include non-response,
errors in reporting by respondents or recording of answers
by interviewers, and errors in coding and processing data.
Every effort is made to reduce non-sampling error by careful
design and testing of questionnaires, training and
supervision of interviewers, and extensive editing and
quality control procedures at all stages of data processing.
Only data with a relative standard error (RSE) of less than
25% are included in the publication commentary (unless
otherwise noted), and any differences between populations
and changes over time that are referred to are statistically
significant. All data contained in the commentary are
available for download as data cubes from the Downloads tab.
For more information about relative standard error and
statistical significance refer to the
Technical Note.
Interpretation of results
Crime victimisation surveys are best suited to measuring
crimes against specific individuals or households.
Respondents need to be aware of and recall what happened to
them and how it happened, as well as be willing to relate
what they know to interviewers.
Not all types of crime are suitable for measurement by
household surveys. No reliable information can be obtained
about crimes without specific victims, such as trafficking
in narcotics. Crimes of which a person may not be aware
cannot be measured effectively through a household survey,
for example crimes involving deception. It may also be
difficult to obtain information about some crimes, such as
sexual offences and assault committed by other household or
family members, due to the sensitivity of the crime and an
increased reluctance to disclose. Some of these crimes may
not be fully represented in the data collected. Household
survey data exclude crimes against commercial establishments
or government agencies.
This survey covered only selected types of personal and
household crimes and does not represent all crime in
Australia.
Personal crimes covered in the survey were
-
-
physical assault,
-
threatened assault (face-to-face and
non-face-to-face),
-
robbery; and
-
sexual assault.
Household
crimes covered were -
-
break-in,
-
attempted break-in,
-
motor
vehicle theft,
-
theft from a motor vehicle,
-
malicious
property damage and
-
other theft.
Information collected in this survey is essentially 'as
reported' by respondents and hence may differ from that
which might be obtained from other surveys or administrative
data sources. This factor should be considered when
interpreting the estimates and when making comparisons with
other data sources.
Experiences of family and domestic violence
There is limited information available in this publication
about family and domestic violence. The Crime Victimisation
Survey collects information about experiences of personal
violence and the relationship between the victim and
perpetrator, however this information alone is not
sufficient to reliably measure the number of people who have
experienced family and domestic violence.
The Crime Victimisation Survey collects incident
characteristics information, including relationship to the
offender, only for the most recent incident of each type of
personal crime experienced in the 12 months prior to
interview. This means that not all experiences of personal
violence by each relationship type - including current and
previous partners - are captured in the survey. In addition,
as interviews are conducted by telephone in the respondent’s
home, there is no requirement for a private interview
setting for the Crime Victimisation Survey (as is the case
for the ABS’s Personal Safety Survey). This non-private
setting means respondents may be less likely to disclose any
experiences of violence by their partner if their partner is
present in the home at the time of interview. As a result,
the statistics on relationship type available in this
publication cannot be used to draw conclusions about the
prevalence of family and domestic violence in Australia.
Due to the ongoing relationship between victim and
perpetrator, family and domestic violence is often a
recurring event, and the protracted nature of this violence
cannot be reliably measured within the framework of the
Crime Victimisation Survey. Further information about
defining and measuring family and domestic violence is
available in
Defining the Data Challenge for Family Domestic and Sexual
Violence, 2013 (cat. no. 4529.0) and statistics are
available in
Personal Safety, Australia, 2016 (cat. no. 4906.0),
Directory of Family, Domestic, and Sexual Violence
Statistics, 2018 (cat. no. 4533.0), and
Recorded Crime - Victims, Australia, 2017 (cat. no. 4510.0).
Statistical measures of crime victimisation
The level of victimisation can be measured and expressed in
more than one way. The most common measure derived from
crime victimisation surveys is prevalence, that is, the
number of the relevant population that have experienced a
given crime at least once in the reference period.
Victimisation rates used in this publication represent the
prevalence of selected crimes in Australia, and are
expressed as a percentage of the total relevant population.
Reporting rates used in this publication are expressed as
the percentage of persons/households whose most recent
incident of each type of crime had been reported to the
police.
Comparability of time series
The 2018-19 Crime Victimisation Survey is the eleventh in a
series of annual Crime Victimisation Surveys conducted by
the ABS. The ten previous surveys in this series included
the majority of the questions asked in 2018-19. As a similar
methodology has been adopted for the surveys, data on the
prevalence of personal and household crimes is comparable
across the survey periods. This has enabled some time series
comparisons to be made in this publication.
The Crime Victimisation Survey series replaced the previous
Crime and Safety Surveys and was introduced because of a
change to the collection methodology. The new method of
collection mainly uses personal telephone interviews of
selected respondents. Data collections between 1990 and 2005
required respondents to complete questionnaires by
themselves and mail these back to the ABS. This difference
in mode of collection and changes to survey content means
that Crime Victimisation Survey data collected using the
MPHS are generally not directly comparable with data from
Crime and Safety Surveys prior to 2008–09.
Comparability with previous Crime Victimisation Surveys
In 2010-11 significant changes to the 'Area of Usual
Residence', 'Capital City' and 'Balance of State/Territory'
geographical items were made. From 2008-09 to 2012-13 the
Australian Standard Geographical Classification (ASGC) (cat.
no. 1216.0) was used to characterise Geographical
Classifications. From 2013-14 onwards the
Australian Statistical Geography Standard (ASGS) (cat. no.
1270.0.55.001) was used. The ASGS is updated on a five
yearly basis in accordance with the Census of Population and
Housing. Consequently, the 2018-19 Crime Victimisation
Survey saw the introduction of the updated ASGS. More
information on this can be found in
Australian Statistical Geography Standard (ASGS): Volume 1 -
Main Structure and Greater Capital City Statistical Areas,
July 2016.
For the 2018-19 reference period, the following data
have
not been published at the state/territory level:
- Robbery;
- Sexual assault;
- Police reporting data for non face-to-face
threatened assault;
- Police reporting data for motor vehicle theft; and
- Contribution of alcohol or another substance data
for physical assault and face-to-face threatened
assault.
A review of data quality found that due to low prevalence
and/or high error or volatility, estimates for the above
data items are too statistically unreliable for general use.
National estimates for these data items are still available
in the data cubes, and users are advised to exercise caution
when using state and territory level data for these data
items from previous iterations of the survey.
Comparability with police statistics
Data for selected crimes reported to and recorded by police
agencies in a calendar year are available in
Recorded Crime - Victims, Australia, 2017 (cat. no. 4510.0).
The Crime Victimisation Survey provides an additional source
of data on crime victimisation for the selected crimes,
including crime not reported to or detected by police. This
survey identifies the nature of this unreported crime, as
well as giving information about experiences of repeat
victimisation. The information from the survey should be
viewed as complementary to police recorded crime statistics.
The terms used for the crimes (such as robbery and physical
assault) may not necessarily correspond with the legal or
police definitions used. This is because responses obtained
in this survey are based on the respondent's perception of
the behaviours they experienced. The definitions of terms
used in the publication are based on the wording of the
questions asked of the respondent and specifications
provided to interviewers. Definitions of crime types
included in this survey can be found in the
Glossary.
The Crime Victimisation Survey collects information on
crimes that were reported to police, as well as crimes that
went unreported. In this publication, reporting rates are
based on whether or not the most recent incident of each
crime type experienced in the 12 months prior to interview
was reported to police. Interviews were conducted over a 12
month period from 1 July 2018 to 30 June 2019. The actual
reference period for a particular respondent was determined
by the date of their interview. There is no way of verifying
that a crime was reported to police, where the respondent
indicated that police were informed.
Another source of variation between the survey results and
crimes recorded by police relates to differences in scope.
This survey collects information on the personal crimes of
physical assault, threatened assault (face-to-face and
non-face-to-face), and robbery for all persons aged 15 years
and over, and sexual assault for persons aged 18 years and
over. In contrast, police statistics include victims of all
ages, and any comparisons should take this into
consideration. Furthermore, police statistics for a given
reference period may include criminal incidents that came to
the attention of police during the reference period, but did
not occur during it.
Due to differences between collections, caution should be
exercised when comparing data from surveys and
administrative by-product collections that relate to crime
and justice topics. For more information on comparisons
between sources, please refer to
Measuring Victims of Crime: A Guide to Using Administrative
and Survey data, June 2011 (cat. no. 4500.0.55.001).
Comparability with other ABS surveys
Caution should be exercised when comparing across ABS
surveys and with administrative by-product data that address
the access and use of health services. Estimates from the
Crime Victimisation Survey may differ from those obtained in
other surveys (such as the Personal Safety Survey, National
Aboriginal and Torres Strait Islander Health Survey,
National Aboriginal and Torres Strait Islander Social
Survey, and General Social Survey) due to differences in
survey mode, methodology and questionnaire design.
Comparability with monthly LFS Statistics
Since the Crime Victimisation Survey is conducted as a
supplement to the Labour Force Survey (LFS), data items
collected in the LFS are also available in this publication.
However, there are some important differences between the
two surveys. The LFS had a response rate of over 90%
compared to the MPHS response rate of 71.8%. The scope of
the Crime Victimisation Survey and the LFS also differ, as
outlined in the preceding sections. Due to the differences
between the samples, data from the Crime Victimisation
Survey and the LFS are weighted separately. Variances may
therefore be found in the estimates for those data items
collected in the LFS and published as part of the Crime
Victimisation Survey.
Other methodological issues
When interpreting data from the 2018-19 MPHS, consideration
should be given to the representativeness of the survey
sample in relation to the entire in-scope population. This
is affected by the response rate and scope and coverage
rules. For example, people living in boarding houses,
refuges or on the streets are excluded from this survey and
may experience different levels of victimisation than those
surveyed who live in private dwellings.
Equivalised Weekly Household Income
Equivalised weekly household income is household income
adjusted by the application of an equivalence scale to
facilitate comparison of income levels between households of
differing size and composition, reflecting that a larger
household would normally need more income than a smaller
household to achieve the same standard of living. Using an
equivalising factor for household income enables the direct
comparison of the relative economic well-being of households
of different size and composition (for example, lone person
households, families and group households of unrelated
individuals).
For more information about equivalised weekly household
income see
Household Income and Wealth, Australia (cat. no. 6523.0)
and
Survey of Income and Housing, User Guide, Australia (cat.
no. 6553.0).
Socio-Economic Indexes for Areas (SEIFA)
Socio-Economic Indexes for Areas (SEIFA) is a classification
developed by the ABS that ranks areas in Australia according
to relative socio-economic advantage and disadvantage. SEIFA
uses a broad definition of relative socio-economic advantage
and disadvantage in terms of people's access to material and
social resources, and their ability to participate in
society.
The indexes are based on information from the five-yearly
Census, and each index summarises a different aspect of the
socio-economic conditions of people living in an area. Every
geographic area in Australia is given a SEIFA number which
shows how disadvantaged or advantaged that area is compared
with other areas in Australia.
The Crime Victimisation Survey uses two indexes from the
2016 Socio-Economic Indexes for Areas (SEIFA) – the Index of
Relative Socio-Economic Advantage and Disadvantage; and the
Index of Relative Socio-Economic Disadvantage. These
measures are derived from Census variables related to
income, educational attainment, unemployment, occupational
skill level and whether a dwelling has a motor vehicle.
For more detail, see the following:
Geography
Australian geographic data are classified according to the
Australian Statistical Geography Standard (ASGS): Volume 1 -
Main Structure and Greater Capital City Statistical Areas,
July 2016 (cat. no. 1270.0.55.001). Remoteness areas are
classified according to the
Australian Statistical Geography Standard (ASGS): Volume 5 -
Remoteness Structure, July 2016 (cat. no. 1270.0.55.005).
Country of birth
Country of birth data are classified according to the
Standard Australian Classification of Countries (SACC), 2016
(cat. no. 1269.0).
Education
Education data are classified according to the
Australian Standard Classification of Education ASCED, 2001
(cat. no 1272.0). The ASCED is a national standard
classification which can be applied to all sectors of the
Australian education system including schools, vocational
education and training and higher education. The ASCED
comprises two classifications: Level of Education and Field
of Education.
Products and services
Data cubes containing all tables for this publication in
Excel spreadsheet format are available from the Downloads
tab. The spreadsheets present tables of estimates and
proportions, and their corresponding relative standard
errors (RSEs).
As well as the statistics included in this and related
publications, the ABS may have other relevant data available
on request. Subject to confidentiality and sampling
variability constraints, tables can be tailored to
individual requirements. A list of data items from this
survey is available from the Downloads tab. All enquiries
should be directed to the
National Information and Referral Service on 1300 135
070, or email
client.services@abs.gov.au.
Acknowledgements
ABS surveys draw extensively on information provided by
individuals, businesses, governments and other
organisations. Their continued cooperation is very much
appreciated and without it, the wide range of statistics
published by the ABS would not be available. Information
received by the ABS is treated in strict confidence as
required by the
Census and Statistics Act 1905.