Crime Victimisation, Australia methodology

Survey estimates of counts of persons are obtained by summing the weights of persons with the characteristic of interest.

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).

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 2020. People living in Indigenous communities were excluded. These benchmarks are based on the 2016 Census.

While LFS benchmarks are revised every 5 years, to take into account the outcome of the 5-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 surveys estimates, as well as over time. If comparisons are being made over time then proportions should be used rather than estimates of persons.

The estimates in this publication are based on information obtained from a sample survey. Any data collection may encounter factors, known as non-sampling error, which can impact on the reliability of the resulting statistics. In addition, the reliability of estimates based on sample surveys are also subject to sampling variability. That is, the estimates may differ from those that would have been produced had all persons in the population been included in the survey. This is known as sampling error.

Non-sampling error is caused by factors other than those related to sample selection. It is any factor that results in the data values not accurately reflecting the true value of the population.

It can occur at any stage throughout the survey process. Examples include:

• selected people that do not respond (e.g. refusals, non-contact) 
• questions being misunderstood
• responses being incorrectly recorded
• errors in coding or processing the survey data.

Sampling error is the expected difference that can occur between the published estimates and the value that would have been produced if the whole population had been surveyed. Sampling error is the result of random variation and can be estimated using measures of variance in the data.

One measure of sampling error is the standard error (SE). There are about two chances in three that an estimate will differ by less than one SE from the figure that would have been obtained if the whole population had been included. There are about 19 chances in 20 that an estimate will differ by less than two SEs.

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.

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 perpetrator, 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’ 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 and statistics are available in Personal Safety, Australia, Directory of Family, Domestic, and Sexual Violence Statistics, 2018, and Recorded Crime - Victims, Australia.

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.

Country of birth data are classified according to the Standard Australian Classification of Countries (SACC), 2016. 

Education data are coded to the Australian Standard Classification of Education (ASCED), 2001. 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.

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 and Survey of Income and Housing, User Guide, Australia.

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. Remoteness areas are classified according to the Australian Statistical Geography Standard (ASGS): Volume 5 - Remoteness Structure, July 2016.

This survey uses the 2016 Socio-Economic Indexes for Areas (SEIFA).  

SEIFA is a suite of four summary measures that have been created from 2016 Census information. Each index summarises a different aspect of the socio-economic conditions of people living in an area. The indexes provide more general measures of socio-economic status than is given by measures such as income or unemployment alone.

For each index, every geographic area in Australia is given a SEIFA number which shows how disadvantaged that area is compared with other areas in Australia.

Two indexes are used in this publication – 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.

SEIFA uses a broad definition of relative socio-economic disadvantage in terms of people's access to material and social resources, and their ability to participate in society. While SEIFA represents an average of all people living in an area, it does not represent the individual situation of each person. Larger areas are more likely to have greater diversity of people and households.

For more detail, and for the SEIFA 2016 Technical paper (under Downloads), go to Census of Population and Housing: Socio-Economic Indexes for Areas (SEIFA), Australia, 2016.

Includes any illegal or legal drugs or mood altering substances that the person believed contributed to the most recent incident of physical assault or face-to-face threatened assault. Other substances include marijuana, cocaine, ice, heroin, ecstasy, steroids, pharmaceuticals, inhalants, kava etc. Either the victim or perpetrator may have been under the influence of alcohol and/or any other substance at the time of the incident. This also includes:

• incidents that occurred when the victim or perpetrator were ‘hungover’
• incidents where the victim believed that their drink had been spiked.

For this survey, only persons aged 18 years and over were asked questions about alcohol and other substance use, and respondents had the option of refusal to answer.

An incident where an attempt was made to forcibly enter a home or other private residence. Includes attempts to break into a caravan (if the caravan was the person's permanent residence), garage, shed or any detached secure building such as games/hobby rooms or granny flats. Attempted break-in also includes incidents where a person saw someone acting suspiciously around the property, if it was suspected that their intent was to break in and steal property. Excludes any attempted break-in that resulted in an actual break-in (e.g. where someone attempted to break in through a door but then gained entry through a window) and attempted break-in to a motor vehicle.

Includes both physical assault and threatened assault (both face-to-face threatened assault and non-face-to-face threatened assault).

Comprises statistical areas outside the Greater Capital City Statistical Areas of states and territories as defined in the Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, July 2016.

An act of unauthorised forced entry into a home or other private residence. Includes forced entry to a caravan (if the caravan was the person's permanent residence), garage, shed or any detached secure building such as games/hobby rooms or granny flats. Excludes forced entry into motor vehicles or front or rear yards and incidents where attempts to gain unlawful entry were not successful (see attempted break-in above).

Refers to the Greater Capital City Statistical Areas of states and territories as defined in the Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, July 2016.

All people aged 15 years and over who met one of the following criteria during the reference week:

• Worked for one hour or more for pay, profit, commission or payment in kind, in a job or business or on a farm (employees and owner managers of incorporated or unincorporated enterprises).
• Worked for one hour or more without pay in a family business or on a farm (contributing family workers).
• Were employees who had a job but were not at work and were:
  • away from work for less than four weeks up to the end of the reference week; or
  • away from work for more than four weeks up to the end of the reference week and received pay for some or all of the four week period to the end of the reference week; or
  • away from work as a standard work or shift arrangement; or
  • on strike or locked out; or
  • on workers' compensation and expected to return to their job.
• Were owner managers who had a job, business or farm, but were not at work.

Any verbal and/or physical threat to inflict physical harm, made face-to-face, where the person being threatened believed the threat was likely and able to be carried out. Excludes any incident where the person being threatened did not encounter the perpetrator in person (e.g. threats made via telephone, text message, e-mail, in writing or through social media) – these incidents are counted under non face-to-face threatened assault.

Includes parent, child, sibling or other family member.

Employed people who usually worked 35 hours or more a week (in all jobs) and those who, although usually working less than 35 hours a week, worked 35 hours or more during the reference week (i.e. the week before the interview).

Greater Capital City Statistical Areas (GCCSA) are geographical areas built from Statistical Areas Level 4 (SA4), as defined in the Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, July 2016. They are designed to represent the functional extent of each of the eight State and Territory capital cities. This includes the population within the urban area of the city, as well as people who regularly socialise, shop or work within the city, and live in small towns and rural areas surrounding the city. Within each State and Territory, the area not defined as being part of the Greater Capital City is represented by a Balance of State/Territory region.

A group of two or more related or unrelated people who usually reside in the same dwelling, who regard themselves as a household, and who make common provision for food or other essentials for living; or a person living in a dwelling who makes provision for their own food and other essentials for living, without combining with any other person.

Crimes that were committed with the intent to deprive another person of, or deliberately damage, their personal property. The selected household crimes included in the survey are break-in, attempted break-in, motor vehicle theft, theft from a motor vehicle, malicious property damage and other theft. Includes incidents occurring in all Australian households that the person lived in during the 12 months prior to interview. For the purposes of the survey, the household is considered the victim where anyone living in the household (not only the respondent) may have experienced an incident of household crime during the 12 months prior to interview. Excludes incidents where personal property was stolen by force or threat from a person in the household.

A single occurrence of a crime event, which may involve one or more crime types.

Includes current partner, previous partner, boyfriend/girlfriend/ex-boyfriend/ex-girlfriend or date.

Where the person recognised the perpetrator(s) by sight only but did not have a personal relationship with them.

A classification of the civilian population aged 15 years and over, including employed, unemployed or not in the labour force, as defined in Labour Force, Australia. These definitions conform closely to the international standard definitions adopted by the International Conference of Labour Statisticians.

Non-school qualifications are awarded for education attainments other than those of pre-primary, primary or secondary education. They include qualification at the following levels: Postgraduate degree, Master degree, Graduate Diploma and Graduate Certificate, Bachelor degree, Advanced Diploma and Diploma and Certificates I, II, III and IV. Non-school qualifications may be attained concurrently with school qualifications.

Intentional or wilful (not accidental) damage, defacement or destruction of any part of the person's home or anything usually kept at home. Property is something tangible in nature, including land, conveyances, animals or other objects capable of being privately owned. Destruction can mean any alteration that may render something imperfect or inoperative, including destruction of property, graffiti or vandalism, partial destruction, killing or harming an owned animal and removing or destroying a plant or other part of an owned landscape. Excludes any rental, investment or holiday properties owned by a member of the household. Excludes acts such as turning off water meters and flicking safety switches if no damage to the item occurred.

Includes incidents where a person was admitted to hospital and incidents where a person was seen by a doctor or another medical practitioner but not admitted to hospital.

Examples include license plates, tyres, wheels/rims, car audio and DVD equipment.

An incident where a motor vehicle was stolen from any member of the household. This includes cars, SUVs, motorcycles (including motorised scooters), buses, trucks and motor homes. Includes privately owned vehicles and business/employer/company owned vehicles only if the vehicle was used exclusively by members of the household. Excludes vehicles used mainly for business purposes, boats, trailers and company vehicles not used exclusively by household members. For the purpose of this survey, motor vehicle theft incidents are considered to be household crimes.

Any threat to inflict physical harm where the person being threatened believed the threat was likely and able to be carried out, and where they did not encounter the perpetrator face-to-face (e.g. via telephone, text message, e-mail, in writing or through social media).

Persons who were neither employed nor unemployed as defined by Labour Force Status.

Used to describe the relationship of the perpetrator to the victim where the perpetrator was known to the victim, but the relationship did not match any of the known person categories specified in the survey.

Any unlawful taking of money or goods owned by a household member (other than from motor vehicles owned by a household member) with the intent to permanently deprive the owner of the money or goods, without the use or threat of force or violence, coercion or deception. Includes:

• property belonging to a member of the household not covered by the other types of crime included in the survey
• property belonging to a household member stolen from a vehicle not owned by a household member
• property stolen from a yard or garden (e.g. statues or plants).

Excludes any incidents involving theft covered in other crime types in the survey (e.g. property stolen during a break-in or robbery). Other theft is considered to be a household crime for the purposes of the survey.

Employed people who usually worked less than 35 hours a week (in all jobs) and either did so during the reference week (i.e. the week before the interview), or were not at work in the reference week.

A person who commits a crime, as identified by the person who experienced the crime. There may be one or more perpetrators involved in any single crime incident.

Crimes that were committed against a person which threatened or caused physical harm to the person. The types of personal crime included in the survey are physical assault, threatened assault (including face-to-face threatened assault and non face-to-face threatened assault), robbery (including attempts), and sexual assault (including attempts).

An act of physical force or violence committed by a perpetrator(s) against another person. Examples of physical force or violence include being beaten, pushed, grabbed, shoved, slapped, hit with an open hand or fist, kicked, bitten, choked, stabbed, shot, burnt, being hit with something such as a bat or being dragged or hit deliberately by a vehicle. Includes assault that occurred while the person was at work. Excludes incidents that occurred during the course of play on a sporting field or organised sport, and incidents of sexual assault which also involved physical assault (these are counted under sexual assault).

State and territory police agencies. Excludes federal police, except in the Australian Capital Territory.

Any motor vehicle used mainly for private purposes (i.e. non-business purposes).

A relationship where the perpetrator was known to the person primarily through the course of the person's and/or perpetrator’s occupation. Includes where the person was working in a business for which the perpetrator was a client at the time of the incident; relationships between medical professionals and patients; and relationships between police/security officers and perpetrators.

Includes buses, trains, trams, ferries and taxis.

Refers to a formal certification, issued by a relevant approved body, in recognition that a person has achieved an appropriate level of learning outcomes or competencies relevant to identified individual, professional, industry or community needs. Excludes statements of attainment awarded for partial completion of a course of study at a particular level.

Refers to the relationship of the perpetrator to the victim at the time of the incident, as perceived by the victim. More than one response could be provided if there were multiple perpetrators involved in the incident.

A measure of the extent to which an estimate might have varied by chance because only a sample of dwellings was surveyed, and not the entire in-scope population. Relative standard error (RSE) is obtained by expressing the standard error as a percentage of the estimate.

The total number of persons/households that reported the most recent incident of a crime type to police, expressed as a percentage of the total number of persons/households that experienced the crime type. Includes incidents where the person who experienced the crime did not report the incident themselves, but were aware of another person who did.

An act of stealing (or attempting to steal) property from a person by physically attacking them or threatening them with force or violence. Includes incidents that occurred at the person's place of work. Excludes pickpocketing or other types of theft from a person that did not involve physical or threatened violence (these are counted under other theft).

An act of a sexual nature carried out against a person's will or without their consent, through the use of physical force, intimidation or coercion and/or involving physical contact. Includes any actual or attempted forced sexual activity such as rape, attempted rape or indecent assault (e.g. being touched inside clothing or intentional rubbing of genitals against the person) and assault with the intent to sexually assault. Includes incidents that occurred at the person's place of work. Excludes sexual harassment that did not involve or lead to an actual or attempted sexual assault. For this survey, only persons aged 18 years and over were asked questions about sexual assault, and respondents had the option of refusal to answer.

The relationship status of an individual in terms of whether they form a couple relationship with another person living in the same usual residence, and the nature of that relationship. A marriage exists when two people live together as husband and wife, or partners, regardless of whether the marriage is formalised through registration. Individuals are, therefore, regarded as married if they are in a de facto marriage, or if they are living with the person to whom they are registered as married.

An incident where property owned by any member of the household was stolen from a motor vehicle owned (for private use) by any member of that household. Excludes property stolen that belonged to someone not living in the household (e.g. a friend or other relative) and property owned by a business or employer (e.g. a work computer, mobile phone or work tools). Also excludes property stolen from commercial vehicles (e.g. a self-employed business operator whose vehicle is mainly used for work purposes) and any break-in to a motor vehicle where nothing was stolen. For the purposes of this survey, incidents of theft from a motor vehicle are considered to be household crimes.

A verbal, written and/or physical threat to inflict physical harm where the person being threatened believed the threat was likely and able to be carried out. Threatened assault may occur face-to-face or via non-face-to-face methods (such as SMS, e-mail or over the phone). Includes any threat or attempt to strike the person which could cause pain; situations where a gun or other weapon was left in an obvious place (including fake or toy guns/weapons where the threatened person thought it was real) or if the person knew the perpetrator had access to a gun (including toy guns, starter pistol, etc.) or weapon. Also includes incidents where the person was threatened in their line of work. Excludes verbal abuse and any incident of name calling or swearing which did not involve a physical threat, and threats that resulted in an actual assault (these are counted under physical assault).

People aged 15 years and over who were not employed during the reference week (i.e. the week before the interview), and:

• had actively looked for full-time or part-time work at any time in the four weeks up to the end of the reference week and were available for work in the reference week
• were waiting to start a new job within four weeks from the end of the reference week and could have started in the reference week if the job had been available then.

A person or household who has experienced at least one incident of a selected type of crime in the 12 months prior to interview. A person/household may have experienced more than one incident of the same crime type, but is only counted as a victim once.

The total number of persons/households that experienced a crime type, expressed as a percentage of all persons/households. This is a measure of how prevalent a crime type is in a given population and is used to measure changes in crime rates over time.

Where the person believed a weapon was present during the crime incident (even if they did not see a weapon), or where a weapon was not used during the incident but the person was threatened that a weapon might be used. Examples include knife, gun, bat/bar, bottle/glass and syringe/hypodermic needle.