2010/11 Scottish Crime and Justice Survey: Drug Use

This report presents findings from the Scottish Crime and Justice Survey 2010/11 Drug Use module. The report provides information on the experience and prevalence of illicit drug use amongst the general adult population in Scotland.

1 Introduction

The Scottish Crime and Justice Survey (SCJS) is a large-scale continuous survey measuring people's experience and perceptions of crime in Scotland. The survey is based on 13,000 in-home face-to-face interviews with adults (aged 16 or over) living in private households in Scotland.

The main aims of the SCJS are to:

  • Provide a valid and reliable measure of adults' experience of crime, including services provided to victims of crime;
  • Examine trends in the number and nature of crime in Scotland over time;
  • Examine the varying risk of crime for different groups of adults in the population;
  • Collect information about adults' experiences of, and attitudes to, a range of crime and justice related issues.

The main findings for 2010/11 are presented in a series of four reports. This report presents the key findings about illicit drug use collected through the self-completion section of the survey. A Technical Report and User Guide are also available.[2]

The SCJS is the only source of information on self-reported drug use among the general adult population of Scotland as a whole (Box 1.1). Information on experience of illicit drug use was collected through the self-completion section of the questionnaire, which was completed by 10,999 (85%) of the 13,010 respondents to the main SCJS questionnaire.

The data for the survey are available on the UK Data Archive in SPSS format.[3] The analysis in this report is not exhaustive, and readers are encouraged to conduct their own analysis of the primary data. Supporting documentation for the survey, as well as generic teaching datasets, is also provided on the UK Data Archive.

1.1 Background

The main aim of the self-completion illicit drug use questions was to establish whether adults aged 16 or over reported using any of 16 specified drugs either at some point in their lives, in the last year and in the last month. In addition to the 16 drugs included in the previous surveys, in 2010/11 5 previously legal 'new' drugs were added to the survey for the first time (see section 1.4). These were BZP, GBL, khat, mephedrone and synthetic cannabinoids. Those who had used any types of drugs were asked a series of follow-up questions to provide more detail about being offered drugs, the first drug they used, and the drug used most often in the last month. Further details of the questionnaire content can be found in Annex 2, section A2.2.

Box 1.1: SCJS data on self-reported illicit drug use in Scotland

The SCJS is the only source of information and trend data on self-reported illicit drug use in the general adult population at national level in Scotland.[4]

The Scottish Government's Drugs Strategy,[5] The Road to Recovery (2008),[6] recognises that recovery from drug use must be tailored to the needs of individuals and highlights the importance of a strong evidence base. A review of the evidence base exploring what works in recovery from drug use was published by the Scottish Government in September 2010 (Best, et al, 2010). However, continued, up-to-date and accurate information on the prevalence of drug use in Scotland is vital in allowing government and other stakeholders to respond promptly and appropriately, and in informing the successful delivery of the drugs strategy.

This report provides information which is of use to national and local policy makers, practitioners, NHS and voluntary service providers to help build a picture of drug use in the general population and provide evidence on the latest trends in drug use for prevention / education work and service-planning purposes.

1.2 Methodology

The SCJS was sampled from private residential addresses in Scotland using the Royal Mail Postcode Address File (PAF). One adult aged 16 years or over per household was then randomly selected for interview. As the survey only included private residential addresses, it is acknowledged that it can under-represent key groups who are likely to use illicit drugs (section 1.3).

Questions on illicit drug use were included in the self-completion section of the questionnaire, which was undertaken at the end of the main SCJS interview. Respondents were handed the interviewer's tablet computer and guided by the interviewer through a series of practice questions which explained how to use the computer. Where respondents were unable or unwilling to use the tablet computer themselves, interviewers administered the interview, showing the respondent the screen and helping them to input their answers.

Participation was voluntary, with 10,999 (85%) of the 13,010 respondents to the main survey completing the self-completion questionnaire. Non-response was higher among adults aged 60 and over (see Annex 2, section A2.5 for further details).

A more detailed explanation of the methodology for the survey can be found in Annex 2, and the accompanying Technical Report.[7]

1.3 Limitations of the data

Self-reporting drug surveys are valuable in providing information on drug use when there are few other sources of available data about the population as a whole. However, it is recognised that such surveys do have limitations.

First, it is likely that there will be an under-representation of some groups who take drugs. In part, this will be due to the fact that some people who use drugs may live in accommodation not covered by a survey of private households (such as the SCJS) including, for example, hostels, prisons and student halls of residence. The survey is likely to under-represent those with the most problematic or chaotic drug use, some of whom may live in accommodation previously described and some of whom may live in private households covered by the survey, yet they may be rarely be at home or be unable to take part in an interview due to the chaotic nature of their lives.

Secondly, despite using Computer Assisted Self-completion Interviewing (CASI) for this module, it is likely there will be a certain amount of under-reporting of illicit drug use among survey respondents. Illicit drug use is an illegal activity and as such some individuals may have felt uncomfortable reporting that they have taken illicit drugs, despite reassurances about confidentiality and anonymity.

Thirdly, questions cover past use over varying periods (ever, in the last year and in the last month) and it is possible that some respondents may simply forget occasional uses of a certain drug, particularly if they last took it a long time ago.

While under-reporting of drug use on surveys such as the SCJS is almost certain, it should be noted that the issues discussed above are unlikely to apply equally across all types of drugs. While a survey such as the SCJS is likely to provide an insight into the more commonly used drugs, in particular cannabis, it may be less effective in providing information for some of the Class A drugs such as opiates or crack cocaine, where a sizeable number of those using these drugs may be concentrated in small sub-groups of the population not covered by the survey (Smith et al., 2011).

In addition, while under-reporting is by far the main limitation of this type of household survey, it is also recognised that some people may report taking drugs when they have not actually done so for a number of reasons. To try and counter this mis-reporting, a non-existent drug (semeron) was included in the list of drugs presented to respondents. Including the name of a fictitious drug is a technique that is commonly used in drug surveys (see for example Smith et al., 2011; Brown and Bolling, 2007; Black et al., 2011). In the SCJS 2010/11, twenty two respondents reported that they had ever taken semeron and were, therefore, excluded from the analysis presented in this report.

1.4 Classification of drugs

The Misuse of Drugs Act 1971 classifies illegal drugs into three categories (Class A, B and C) according to the harm they cause. The 16 drugs that respondents were asked about and their classification under the Act are:

  • Class A, including cocaine, crack, crystal meth, ecstasy, LSD, magic mushrooms, heroin, methadone and amphetamines (if prepared for injection);[8]
  • Class B, including amphetamines (in powdered form) and cannabis;
  • Class C, including ketamine, temazepam, valium and anabolic steroids;
  • Not classified, including poppers and glues, solvents, gas or aerosols.

In addition to reporting by Class, a number of other composite drug groups are reported. These composite groups, and the individual drugs that they include, are:

  • Opiates, including heroin and the illicit / non-prescribed used of methadone;
  • Stimulant drugs, including cocaine, crack, crystal meth, ecstasy, amphetamines and poppers;
  • Psychedelics, including LSD, magic mushrooms and ketamine;
  • Downers / tranquilisers, including temazepam and valium.

The groups include illicit drugs across the legal classifications and reflect the drugs' shared properties, effects and characteristics, providing an additional measure to the class-based categorisation. For example, stimulant drugs may be used interchangeably by the same people at similar times and in similar settings.

Drugs not included in the composite groups such as cannabis, anabolic steroids and glues, solvents, gas or aerosols, are included separately in appropriate figures where sufficient data are available to do this.

In addition to the 16 drugs included in the previous surveys, 5 'new' previously legal drugs were added to the SCJS in 2010/11:

  • Mephedrone (mmcat, 4-mmc, 'meow', 'doves', 'bubbles');
  • BZP (benzylpiperazine);
  • GBL (gamma-butyrolactone, liquid 'e') or GHB (gamma-hydroxybutyrate);
  • Synthetic cannabinoids (such as 'spice', 'space');
  • Khat (quat, qat, qaadka, chat, jaad).

It should be recognised that as these drugs were previously legal, for respondents reporting use of them ever, this does not necessarily represent an illicit activity.

1.5 A note on reference periods

In the survey, respondents were asked about their history of drug use over three different time periods. These, with their respective strengths and limitations, are:

  • Self-reported use ever: whether respondents had used specific drugs at some point in their lives, providing useful contextual information when, for example, examining general attitudes to drugs. However, this is not a useful indicator of current drug use or recent trends since it can include people who have used a drug once, perhaps a long time ago;
  • Use in the last year: whether respondents had used specific drugs in the year prior to interview. This time frame is generally regarded as the most stable measure of current drug use, especially when analysing trends over time;[9]
  • Use in the last month: whether respondents had used specific drugs in the month prior to interview. This time frame provides the most up-to-date information on usage. However, since it is a relatively short time period it is more prone to variation, for example, it may miss people who use drugs regularly but who have not done so within the last month.

1.6 Comparing the SCJS 2010/11 with the BCS 2010/11

Due to the fact that the British Crime Survey (BCS) 2010/11 self-completion questionnaire was asked of respondents aged between 16 and 59 years while the SCJS was asked of respondents of 16 years and over (i.e. including those aged 60 or over), care should be taken when comparing SCJS and BCS data. In this report, where comparisons are made with the BCS 2010/11, the SCJS 2010/11 data have been filtered to exclude those aged 60 years and over.

1.7 Structure of the report

This report looks at self-reported illicit drug use among adults in Scotland. Chapter 2 focuses on prevalence of drug use ever (that is, at least some point in a person's life), at least once in the last year (i.e. the year prior to interview) and at least once in the last month (i.e. the month prior to interview) among all adults aged 16 or over.

It looks at key trends in the use of different types of drugs, comparing findings with the SCJS 2008/09 and the SCJS 2009/10 as well as findings for England and Wales using results from the BCS 2010/11. Variations in self-reported drug use in terms of some key demographic and socio-economic variables are also explored. The chapter then looks at the likelihood of being offered drugs in the last year, again highlighting any demographic and socio-economic differences. The chapter concludes by looking at the prevalence of the 'new' previously legal drugs included in the SCJS 2010/11.

Chapter 3 looks in more detail at the experiences of respondents who reported taking drugs at some point in their lives, firstly looking at self-reported drug use in the last year, followed by use in the month prior to interview. Providing more in-depth analysis, the chapter then looks more specifically at the drug reported as being used most often in the last month, the frequency with which these drugs were taken and the extent of dependency. The ease with which adults were able to obtain drugs is explored along with polydrug use; that is, mixing drugs with other drugs or alcohol. The chapter concludes with a look at first experiences of drug taking, including which drug was first taken and at what age.


Email: Stuart King

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