Home Office: Research and Statistics Directorate and predecessors: British Crime Survey Datasets
Home Office: Research and Statistics Directorate and predecessors: British Crime Survey Datasets
The British Crime Survey (BCS) is one of the most important methods used by the Home Office to gather information on crime in England and Wales; ten surveys dating from 1982 to 2001 are held in this series. The survey asks a representative sample of the adult population about their experiences as victims of household crimes and personal crimes during the previous year. Its main purpose was to provide an alternative to police measurement of crime in England and Wales.
The questions asked in the BCS have evolved over time. Most questions relating to the experiences of crime victims have remained the same, but questions on other topics have varied with different sweeps of the BCS. The following is a summary of the types of information gathered in the different sweeps of the survey:
The data gathered in the BCS is intended to complement the Home Office's published statistics on notifiable offences, i.e. crimes reported to and recorded by the police which the police are required to notify to the Home Office. The BCS captures household and personal crimes which were not reported to the police, or not recorded by the police, or not in those categories of crimes which the police were required to notify to the Home Office. It therefore provides a truer estimate of the extent of household and personal crimes. BCS data is also less prone than the statistics on notifiable offences to changes in police practices in recording crimes, and to changes in the willingness of the public to report crimes, so it can provide a more accurate indication of trends in crime over time. The survey provides demographic profiles of the victims of crime (highlighting those groups which are most at risk of victimisation), and also provides information about the nature of crime, the circumstances in which crime takes place, and the impact of crime. Respondents are also asked for their opinions on related topics such as sentencing, the police, and the efficacy of the criminal justice system. The results of the BCS have been published by the Home Office in a variety of statistical and research publications, and are used to measure trends in crime, to provide a point of comparison for statistics on notifiable offences, and to inform policy making on crime and punishment.
It should be noted that the BCS does not cover all crimes, only those classed as household crimes (e.g. burglary, thefts of and from vehicles, vandalism and theft from the home), and personal crimes (e.g. assaults, robberies, thefts from the person and other personal thefts). The BCS does not cover crimes against organisations (e.g. fraud, shoplifting), 'victimless' crimes (e.g. drug abuse) or crimes where the victim is no longer available for interview (e.g. murder, manslaughter). As the core sample in each sweep of the BCS covers adults aged 16 and over, the BCS does not record crimes against children (the exception is the 1992 survey, which included an additional sample of 12-15 year olds from households where an adult was also interviewed).
The datasets in this series are available to download. Links to individual datasets can be found at piece level.
Hardware: 1982-1999, VAX 6410 mainframe.
Operating System: VMS, Microsoft Windows NT subsequently.
Application Software: BLAISE developed by Statistics Netherlands, offering: computer-assisted personal interviewing (CAPI), Computer-assisted telephone interviewing (CATI), and Computer-assisted self interviewing; Interactive data editing; forms-based data entry; structured questionnaire design; complex routing and checking; top-down editing with interactive tables; survey management; data manipulation and tabulation; interactive coding; export to statistical and database packages. Until 1999, data sent to the Home Office in SPSS was exported into P-STAT, software used by the Home Office to hold and manipulate BCS data. From 2001, this was changed to Quancept CAPI, produced by SPSS. The related Quanquest module was used to author the questionnaire, which was designed to replicate the BLAISE surveys.
User Interface: The datasets were accessed via a Windows-type interface. Files were opened and manipulated using SPSS Data Editor, in which data was displayed in a tabular format. Dialogue boxes could be used for basic manipulation; separately created syntax files were used for more complex manipulations.
Logical structure and schema: Before the migration of the BCS datasets from P-STAT to SPSS (in 1999), datasets consisted of separate tables which corresponded, broadly, to the main sections of the survey questionnaire. Since 1999 each dataset has primarily consisted of two tables: one for data from the Victim Forms section (the 'vf' table), the other for data from all other sections of the questionnaire (the 'nonvf' table). From 1994 the datasets have field names which normally correspond to the fields used in the interviewing software.
However, the 1984-1992 field names have prefixes indicating the section of the survey questionnaire to which they relate; including: M (Main Questionnaire), V (Victim Forms), FA (Follow-up A), FB (Follow-up B), D (Demographics) and SC (Self-completion).
How data was originally captured and validated: BCS data is gathered from a 'core' sample of adults aged 16 and over. The first four surveys (1982-1992) achieved successful interviews with a core sample of between 10,000 and 11,000 respondents in England and Wales. In 1994 it was decided to increase the core sample to around 15,000 adults in England and Wales; the sample was further increased to 19,411 for the 2000 survey, and 37,170 in 2001/2002.
In the first three surveys electoral registers were used as a sampling frame. By 1988 it was acknowledged that the use of electoral registers was flawed, because they do not cover all households. The 1992 survey and all subsequent sweeps of the BCS have based their sampling frame on the Postcode Address File (PAF).
In 2000 primary stratification by inner city and non inner city was abandoned; instead, primary sampling was done by Police Force Area (PFA). In response to the higher incidence of crime in inner city areas, every BCS from 1982 until 1998 oversampled these areas by a factor of about two. The 2000 BCS abandoned the oversampling in favour of an oversampling of the smallest PFAs, in order to ensure a minimum number of achieved interviews per PFA.
The 1988-1996 and 2000-2001/2 sweeps employed 'booster' samples of ethnic minorities. These methods produced booster samples of 1,349 ethnic minority respondents in 1988, increasing to a peak of 3,874 in 2000. The 1992 BCS also employed a one-off booster sample of children aged 12-15, from households where an adult had already been interviewed.
In 2000 the Home Office announced that, with effect from 2001, the BCS would be held on an annual rather than a biennial basis and would aim for a larger sample of around 40,000 adults (including ethnic minority booster). In preparation for the enlarged survey the Home Office commissioned a review of BCS methodology; it recommended:
Paper forms were used in the BCS until the 1994 sweep, when Computer Assisted Personal Interviewing (CAPI) using BLAISE was introduced. In CAPI, answers to survey questions are logged by the interviewer onto a laptop computer. CAPI was used for all sections of the BCS questionnaire except for the Self-completion sections, where Computer Assisted Self Interviewing (CASI) was used. Under CAPI/CASI, the entire interview consists of one electronic questionnaire.
Coding and classification: The input, coding and checking responses was done by coders employed by the contractor(s) carrying out each sweep of the survey. This included coding the occupation, social class, etc. of the respondent and the head of household; and coding the offences recorded on Victim Forms, according to a standard scheme for classifying offences. The BCS's instructions for classifying offences were developed by the Home Office in consultation with a number of police forces.
After the introduction of CAPI/CASI in 1994, post-interview coding involved the editing and checking of data input as part of the interview. This included checking 'open-ended' questions, where a response was recorded in the respondent's own words. In the 1992 survey the contractor developed a computer program which suggested the most likely classification for an offence, based on a range of variables recorded in the Victim Forms. Similar programs were used in subsequent sweeps. The classifications suggested by the computer were confirmed or modified by coders.
Weighting: In each sweep data has been weighted at the data processing stage, to correct for imbalances in the sampling and design of the interview. Every BCS sweep has used a series weight to account for the fact that series incidents are recorded on a single Victim Form, and an inner-city weight to correct for inner city oversampling.
Other weights include:
Constraints on the reliability of the data: The BCS faces difficulties in accurately representing the entire population. The Postcode Address File was adopted to help overcome this problem. May also tend to over-represent older age groups. Because of the small number of incidents, estimates of sexual offences are not likely to be reliable. It also undercounts crimes where the victim and offender know each other.
Validation performed after transfer: Details of the content and transformation validation checks performed by NDAD are contained in the catalogues of individual datasets.
Copies of the BCS datasets for 1982-2002 have been deposited by the Home Office in the UK Data Archive (http://www.data-archive.ac.uk/), reference numbers 1869 (for 1982), 2077 (for 1984), 2706 (for 1988), 3202 (for 1992), 3591 (for 1994), 3832 (for 1996), 4081 (for 1998), 4463 (for 2000), 4786 (for 2001) and 4787 (for 2001-2002).
|Held by:||The National Archives, Kew|
|Copies held at:||Copies of British Crime Survey datasets for 1982-2002 are held in the UK Data Archive (see separated material for more details).|
|Former reference in The National Archives||CRDA/2|
|Legal status:||Public Record|
|Creator:||Home Office, 1782-|
|Physical description:||11 datasets and documentation|
|Restriction on use:||Access restrictions apply to certain fields and tables within individual datasets. The British Crime Survey (BCS) datasets and related dataset documentation are Crown Copyright; copies may be made for private study and research purposes only. The Home Office recommends that users should contact Research Development and Statistics Directorate for advice before undertaking analysis of BCS data.|
|Access conditions:||Open unless otherwise stated|
|Immediate source of acquisition:||United Kingdom National Digital Archive of Datasets|
|Custodial history:||Originally transferred from the Home Office. The United Kingdom National Digital Archive of Datasets (NDAD) held the datasets until 2010, when they were deposited at The National Archives (TNA).|
|Accruals:||Further accruals are expected.|
|Publication note:||Publications relating to the BCS have been published by the Home Office's Research Development and Statistics Directorate, and its predecessors, in a number of publication series: Research Bulletins, Statistical Bulletins, Home Office Research Studies, Research and Planning Unit Papers, Research Findings, Occasional Papers and Policing and Reducing Crime Unit Briefing Notes.|
|Unpublished finding aids:||Extent of documentation: 168 documents, Dates of creation of documentation: 1975-2005|
|Administrative / biographical background:||
The first sweep of the British Crime Survey (BCS) was conducted in 1982 by the Home Office and the Scottish Office. It covered 10,905 respondents in England and Wales and 5,031 respondents in Scotland. Subsequent sweeps of the survey were conducted in 1984, 1988, 1992, 1994, 1996, 1998, 2000, and annually from 2001. The 1988 survey was also extended by the Scottish Office to a sample of about 5,000 respondents in Scotland, though as in 1982 the results of the Scottish survey were reported separately. Scottish data is not included in the 1982 and 1988 BCS datasets. The 1984 sweep, and all sweeps of the BCS since 1992, have focused solely on England and Wales. Scotland is covered by a separate Scottish Crime Survey, which was conducted by the Scottish Office in 1993 and 1996, and by the Scottish Executive in 2000. In 1996 the Northern Ireland Office commissioned its own Northern Ireland Crime Survey, using the questionnaire developed for the 1996 BCS. A further Northern Ireland Crime Survey was conducted in 2001.
The BCS was conducted biennially from 1992 until 2000. In 2001 the BCS became an annual survey in which data was gathered through continuous interviewing.
Responsibility for the management of the BCS and the reporting of the survey's results rested (in 2002) with the Crime Surveys Section, which was part of the Crime and Criminal Justice Unit within the Research Development and Statistics Directorate (RDS) of the Home Office. The 1982-1996 surveys were carried out by a predecessor body, the Home Office's Research and Planning Unit, which became part of the Home Office's Research and Statistics Department (another of RDS's predecessors) in 1989-1990.
Although overall control of the BCS rests with the Home Office, certain tasks - fieldwork, piloting, sample design, question coding and some question development - have always been delegated to one or more outside contractors (in some surveys, two contractors have acted as a consortium). The contractors have included: