A systematic mapping of substance use, misuse, abuse and addiction prevention research: current status and implications for future research

ABSTRACT

Background: Since the turn of the millennium, research within the field of substance-related problems has grown rapidly. This paper maps the effectiveness of existing research on substance use, misuse, abuse, and addiction prevention.

Method: In this systematic mapping review, we searched the Web of Science, PubMed, and PsycINFO using multiple terms related to substance use, misuse, abuse, and addiction prevention to assess systematic reviews evaluating prevention interventions. All records were assessed by two independent reviewers. Information about population, substances targeted, and effectiveness were extracted for each of the included reviews. The evaluated interventions were categorized into 12 types of interventions.

Result: For the 532 reviews mapped, we found 12 types of interventions dividedinto two major categories: individual-focused interventions (n = 451) and population-based interventions (n = 111). For each intervention category, many reviews showed positive effects for technology-based interventions, multimodal interventions, and drink-driving interventions. The mapping also highlights areas, including physical activity and interventions in specific arenas, where the reviews present very inconsistent results.

Conclusions: The findings presented in this review serve as a guide of existing research that can be used to inform practitioners and policy makers about interventions conducted as well as highlighting important areas for future research.

KEYWORDS:

• Substance abuse
• intervention
• effectiveness
• prevention
• mapping review

Introduction

Harmful substance use, misuse, abuse, and addiction are an important public health problems that widely contribute to morbidity and mortality rates throughout the world (World Health Organization, 2017). For several decades, substantial research efforts have been undertaken to understand the epidemiology of substance use. The knowledge gained from this work has been important in identifying and developing effective prevention and treatment approaches (Newcomb & Locke, 2005).

Some prevention interventions attempt to help individuals develop the motivation and personal skills to act healthy. Others focus on creating environments that support healthy behaviors. Many prevention approaches focus on changing behavior by helping people develop the knowledge, attitudes, and skills they need to change their behavior. Unlike interventions that focus on the individual, population-based or environmental strategies focus on changing the conditions within a community that may lead to substance abuse, including physical, social, or cultural factors (SAMHSA, 2018).

Prevention interventions are typically categorized in primary-, secondary- and tertiary prevention. Primary prevention aims to prevent disease before it ever occurs. This is done by preventing exposure to hazards that cause disease, altering unhealthy or unsafe behaviors. Examples of primary prevention interventions are legislation and enforcement to control substance use. Secondary prevention intervention target groups at risk or subsets of the general population such as children of drug users, i.e., education interventions or screening and brief advice (Nehlin Gordh, 2012). Tertiary prevention aims to soften the impact of an ongoing illness after diagnosis, prevent relapse or focus on rehabilitation. The lines between the different approaches are far from distinct, as is that of prevention and treatment (Ali & Katz, 2015).

Over the last two decades, the field of prevention interventions has rapidly grown and there is a need to increase the knowledge about these types of interventions and their effectiveness. Although systematic reviews have focused on specific interventions, the whole research field has yet to be described. Against this background, this study maps prevention interventions within this field. That is, the objective of this study is to systematically map the existing research regarding interventions for the prevention of harmful substance use, misuse, abuse, and addiction and to answer the following questions:

• What categories of interventions for the prevention of harmful substance use, misuse, abuse, and addiction can be identified in existing research?

• Do any reviews explicitly consider equality and if so, for which populations?

• Which overall tendencies of effectiveness can be traced in the existing research?

• What are the knowledge gaps and what gaps should be prioritized for future research?

Methods

This systematic mapping review uses the framework for scoping reviews suggested by Arksey and O’Malley (2005). The methods of a systematic mapping review aim at a broad overview of a particular research field and therefore usually allow a broader scope than traditional systematic reviews (Arksey & O’Malley, 2005). While a systematic mapping review is useful in its own right by providing a map of existing research within a field, it can also help identify knowledge gaps where researchers can focus in more depth. Thus, a systematic mapping review provides a wider research context within which to interpret the findings of such evidence syntheses (Bates, Clapton, & Coren, 2007; Gough, Oliver, & Thomas, 2013; Oakley, Gough, Oliver, & Thomas, 2005).

Study inclusion and exclusion criteria

The Population/Problem, Intervention, Comparison, and Outcome (PICO) helped us focus the research question and clarify the criteria for inclusion and exclusion (Schardt, Adams, Owens, Keitz, & Fontelo, 2007). In addition to PICO (Table 1), we formulated additional inclusion and exclusion criteria. The literature searches were restricted to articles written in English, Norwegian, Danish, and Swedish (languages known to the authors). The databases were searched from inception to October 2017. All countries, contexts, and settings were included. Due to the broad objective of this study, we were unable to include original research studies. Therefore, only systematic reviews were included. Primary and secondary prevention interventions were included. Tertiary prevention, such as relapse prevention or harm reduction, was excluded. Due to the broad scope of the review, we accepted a broad definition of primary and secondary prevention. The boundaries between secondary and tertiary prevention (as well as treatment) were sometimes difficult to delineate. An example of this was that the same kind of intervention, i.e., brief advice or mindfulness, could be described as prevention in one review and as a treatment in another. After discussions on how to handle this problem, we concluded that interventions conducted by health-care professionals during a longer period, i.e., group sessions inspired by cognitive behavioral therapy, were considered as treatments. Other interventions such as mindfulness were considered as prevention if they were not a part of a rehabilitation program or conducted as a more comprehensive treatment. All pharmacological interventions were excluded.

Table 1. Research question in PICO-format.

Population/Problem: All populations
Intervention: Interventions aiming to prevent use, harmful use, abuse, and addiction of alcohol, illicit drugs and tobacco
Comparison: Not relevant for this systematic mapping review
Outcome: All outcomes related to reduced use of substances
Study design: Systematic reviews

Literature searches

A systematic search for relevant literature was performed in four international bibliographic databases: Web of Science, PubMed, Cochrane, and PsycINFO. Three separate searches combined alcohol, illicit drugs, and tobacco use with terms related to interventions and limitations to study design. Bibliographic records imported from the databases were stored in Endnote®. The literature searches are available in appendix 1.

Screening and relevance assessment

One reviewer performed the initial screening of titles. This screening excluded duplicates and records that were clearly irrelevant to the study. The remaining records were screened by the first and the second author independently and any discrepancies regarding inclusion or exclusion of records were discussed and resolved between the authors. Records of interest were retrieved in full-text and their relevance assessed by the two reviewers independently (a list of excluded studies after full-text assessment are available in appendix 2).

Categorization and analysis

The included publications were all analyzed using NVivo for Mac 11.4.3. For the description of included studies, the publications were coded by year of publication, substance, and targeted population.

Publications were coded by type of intervention evaluated and assigned to broader themes, finally creating overall categories of interventions. Publications with specific focus on equality were coded and placed in a separate category.

The overall effectiveness of interventions was presented per identified category and hopefully serves as a guide to further in-depth analyses that consider different settings, populations and specific interventions within the categories (Munn et al., 2018). The results of each of the included reviews were coded as positive effect, no effect, unclear effect, and no information about effects. If results on different outcomes were presented in the same review, the results of the outcome with most relevance to the purpose of the review were extracted, i.e., decrease in substance use. The distribution of reviews showing positive effect, no effect, unclear effect, and no information about effects was then presented for each of the intervention categories.

• Positive effect: A positive effect was explicitly stated in the abstract or result section of the review.

• No effect: It was explicitly stated that the intervention did seem to have an effect.

• Unclear effect: The authors concluded that more research was needed in order to draw firm conclusion about effectiveness.

• No information about effects: The review did not evaluate effects on relevant outcomes, but instead, i.e., map the field.

This way of presenting effects was only meant to provide an initial overview of the overall effects in each category; therefore, we did not differentiate between settings, populations, contexts and other specific characteristics within each of the categories. Thus, the results of this effectiveness mapping should only serve as a guide for future in-depth analyses of the effects of specific categories of interventions (Munn et al., 2018).

Results

Description of the literature

The database searches identified 27 896 individual records (Figure 1), of which 979 were considered potentially relevant and accessed in full-text. Of these, 532 publications met the inclusion criteria (references available in appendix 3).

Figure 1. Study flow chart depicting the record identification and screening process, illustrated according to recommended reporting on systematic reviews (adopted version of Moher, Liberati, Tetzlaff, Altman, The PRISMA Group, 2009).

All publications were journal articles and covered a time span of 37 years, with a rapid expansion of publications from the late 2000s (Figure 2). The majority of publications targeted the prevention of tobacco (n = 366), only 24 publications targeted illicit drug use alone, and 53 publications targeted all substance use (Figure 3).

Figure 2. Overview of the number of systematic reviews identified in international databases from inception to 2017, presented by year (n=532).

Figure 3. Number of systematic reviews distributed by interventions targeting substance type. Note that one systematic review can evaluate more than one intervention targeting different substances.

The majority of publications evaluated interventions targeting children and young adults (n = 297), 37 publications targeted families, and 131 publications targeted the whole population. Other specific populations targeted were pregnant women (n = 32), patients in hospitals (n = 95), military personnel (n = 9), employees (n = 20), and elderly people (n = 5).

Categories of interventions

The analysis of publications resulted in two main categories of interventions: individual-focused interventions (n = 451) and population-based interventions (n = 111) (Figure 4). Note that the reviews could evaluate both individual-focused and population-based interventions. Individual-focused interventions were categorized into seven overall intervention categories, including a broad spectrum of intervention types. Population-based interventions were categorized into five overall categories of interventions. References with information about effectiveness for all the included studies are available in Appendix 3.

Figure 4. Overview of identified categories of preventive interventions within the field of substance abuse.

Individual-focused interventions

Incentives and rewards

Interventions in this category were mentioned in seven reviews that targeted adults with a focus on smoking prevention. Examples of interventions in this category were quit-and-win contests and incentive interventions such as incentive schemes for smoking cessation. Fifty-seven percent (n = 4) of the included reviews showed positive effect, 14% (n = 1) showed no effect, and 29% (n = 2) had no information about effect.

Technology-based interventions

This category was evaluated in 78 reviews. Interventions in this category included mobile applications, web-based programs, text messages, computer programs, and CD-ROM. The interventions focused on the prevention of alcohol, tobacco, and illicit drugs and targeted adults, children, young adults, and other subgroups such as patients in hospitals. Of these reviews, 53% (n = 41) showed a positive effect on outcomes related to reduced substance use, 19% (n = 15) concluded the effect to be unclear, 1% (n = 1) found no effect, and 27% (n = 21) had no information about effects.

Physical activity

A total of 15 reviews described interventions in the category physical activity, including interventions such as different kinds of workouts, yoga, and mindfulness. Workout interventions mainly targeted children, and yoga and mindfulness targeted adult populations. The interventions focused on the prevention of alcohol, drugs, and tobacco. Forty percent (n = 6) of the included reviews showed a positive effect, 7% (n = 1) showed no effect, 47% (n = 7) concluded the evidence was unclear, and 6% (n = 1) had no information about effects.

Interventions in specific arenas

A total of 193 reviews described intervention in the category of interventions in specific areas. Interventions included in this category were interventions in prison, in workplaces, in health-care settings, in churches, in pharmacies, in national defense, as well as in school-based programs and as family interventions. School-based programs were evaluated in 116 reviews and often focused on the prevention of use, misuse, abuse and addiction of all substances. Workplace interventions were mentioned in 23 reviews and mostly focused on the smoking prevention and smoking cessation. In this category, 42% (n = 81) of the reviews showed a positive effect of interventions, 10% (n = 19) showed no effects, 25% (n = 49) showed unclear effects, and 25% (n = 49) had no information about effects.

Multimodal interventions

Multimodal interventions with an individual focus were described in 17 reviews and evaluated for the prevention of alcohol and tobacco. The interventions in this category combined more than one type of intervention technique such as self-help material, combined family and school interventions, and educational interventions in combination with telephone counseling. A positive effect of multimodal interventions was identified in 53% (n = 9) of the reviews, 6% (n = 1) showed no effect, 12% (n = 2) found the effect to be unclear, and 29% (n = 5) had no information about effects.

Advice and motivation

This category includes a wide range of brief advice, brief interventions, and motivational interviewing interventions, self-help material, and telephone quitlines (i.e., phone numbers that reach counselors who are trained to help people resist the temptation of using). A total of 183 reviews were identified for this category. Interventions in this category were evaluated in different arenas such as in schools, workplaces, and health-care settings. Of these reviews, 44% (n = 81) found positive effects, 12% (n = 22) showed no effect, 26% (n = 47) concluded evidence was unclear, and 18% (n = 33) had no information about effects.

Educational interventions

A total of 12 reviews evaluated educational interventions. The interventions targeted adults, gatekeepers, and youth and focused on the prevention of alcohol, drugs, and tobacco. A positive effect of these interventions was identified in 33% (n = 4) of the reviews, 8% (n = 1) showed no effect, 25% (n = 3) found the effect to be unclear, and 33% (n = 4) had no information about effects.

Population-level interventions

Reduce availability

A total of 43 reviews evaluated interventions that sought to reduce the availability of substances (alcohol, drugs, and tobacco) in the community. This category describes different strategies including restriction of sale, reduction of availability for youth (e.g., eliminating vending machines, requiring photo identification for purchase, minimum age requirements for purchase, and penalties for possession) and bans in specific areas such as workplaces, schools, and restaurants. Of these reviews, 47% (n = 27) showed a positive effect (n = 27), 2% (n = 1) showed no effect, 12% (n = 7) found the effects to be unclear, and 39% (n = 22) had no information about effects.

Reduce demand

A total of 54 reviews evaluated interventions focusing on reducing demand, such as media campaigns, product labeling, and warning texts, and restricting advertising and marketing. Of these reviews, 34% (n = 20) showed positive effects, 10% (n = 6) showed no effect, 24% showed unclear effects, and 32% (n = 19) had no information about effects.

Drink-driving

Interventions evaluating drink-driving interventions were evaluated in 14 reviews, including blood alcohol limits, increased police patrols, sobriety checkpoints, ignition interlocks, and designated driver programs. Most of these interventions targeted the use of alcohol, but a few also targeted illicit drugs. Fifty percent (n = 7) of the reviews showed a positive effect, 14% (n = 2) concluded the evidence to be unclear, and 36% (n = 5) had no information about effects.

Interventions in specific community arenas

This category includes six reviews evaluating interventions in nightlife settings and strategies to remove barriers to smoking cessation services. The interventions targeted the use of alcohol and tobacco. Of the reviews, 17% (n = 1) showed a positive preventive effect, 17% (n = 1) concluded the evidence to be unclear, and 67% (n = 4) had no information about effects.

Multimodal interventions

Population-based multimodal interventions were evaluated in seven reviews. Multimodal interventions included in this category are projects where different types of community interventions are combined. The projects described in the reviews focus on combining laws, enforcements, and restrictions or combining media campaigns, community education, and advertisement. Twenty-nine percent (n = 2) of the reviews showed positive effects, 14% (n = 1) showed unclear effects, and 57% (n = 4) had no information about effects.

Systematic reviews adopting an equality perspective

Unhealthy lifestyle habits can adversely affect health in terms of increased risk of future morbidity and mortality. Differences in health-related habits therefore have a significant impact on whether a population develops inequalities in health. Using this information as a point of departure, this paper identifies and visualizes reviews that explicitly highlight interventions based on an equality perspective.

In addition to evaluating the above categorized interventions, 42 of the included reviews also had an explicit aim to evaluate the equality perspective of the targeted interventions. The results could be summarized in three categories: ethnic minorities (n = 25), socioeconomic status (n = 10), and gender and LGBT (n = 7).

Eight of the reviews mapped interventions targeting youth minorities and 15 reviews targeted minority adults. Nine of the reviews evaluated interventions conducted with indigenous populations in the USA, Canada, Australia, and New Zeeland. Two of the reviews focused on interventions targeting pregnant women in ethnic minority groups. The interventions evaluated in the reviews targeted alcohol abuse and illicit drug use.

Ten of the reviews evaluated prevention interventions using a socioeconomic perspective. The reviews evaluated interventions targeting tobacco use. Five of the reviews specifically focused on increased exposure related to socioeconomic status and five reviews evaluated whether the interventions led to increased or decreased equality in the adult population. In total, the reviews showed heterogeneous results and concluded the need for more research in this specific matter.

Seven of the reviews had a gender or LGBT perspective. These interventions targeted tobacco use, alcohol abuse, and illicit drug use. No effect-analyses are stated in this section as they are all included in previous results; however, policymakers are encouraged to investigate further the effects on health equality referring to interventions included in this category.

Discussion

The systematic mapping identified a large amount of research on interventions for the prevention of substance use, misuse, abuse, and addiction. Furthermore, the systematic mapping review identified a number of characteristics of this extensive literature. First, the number of systematic reviews within this field is rapidly expanding. Second, the scientific literature evaluates many prevention interventions. The majority of included reviews focused on individual-focused interventions. This result probably mirrors an established tradition to evaluate, publish, and conduct systematic reviews within this category, rather than a higher attention to individual-focused interventions compared to population-level interventions in society at large.

The mapping of characteristics revealed that a large amount of research has focused on evaluating individual-focused interventions such as brief advice, brief interventions, motivational interviewing, and school-based interventions. Among population-based interventions, the most evaluated interventions were media campaigns, restriction of sales and alcohol, and smoking bans in specific areas. The mapping of effects presented for each intervention category shows that there are many reviews showing positive effects for technology-based interventions, multimodal interventions, and drink-driving interventions. The mapping also highlights areas where the reviews produce very inconsistent results, such as physical activity. These findings should motivate future research such as in-depth analyses of different patterns of positive and negative effects within these categories. Important to note when considering the effectiveness mapping for each of the intervention categories is that no quality assessment has been conducted. The way the effects are presented in this mapping review is an attempt to draw a wide-angel view of the field and the results should only serve as a starting point for further exploration. Within all of the categories, the results of the mapping can guide more deductive reviews by pointing to areas where specific evaluations, including quality assessments, can give useful information.

This systematic mapping review also identified reviews with the explicit aim to conduct equality analyses. Although in-depth equality analyses of all of the included reviews would have been of interest to conduct, the large number of reviews included in this study made such analyses impossible as this approach was outside the scope of our study. However, our findings should be useful for future more in-depth studies.

The purpose of this review was to map the research that has been undertaken on prevention intervention in the field of substance use, misuse, abuse, and addiction. This is, to our knowledge, the first mapping review with the aim to summarize the whole body of literature on prevention interventions within this field. While there are systematic reviews on the efficacy of specific interventions (Black, Mullan, & Sharpe, 2016; Chiesa & Serretti, 2014) and mapping reviews covering specific populations (Cairns, Purves, & McKell, 2014; Heimdahl & Karlsson, 2016), no study to date covers the broader field of prevention interventions. Accordingly, this map can serve as an evidence base for existing research, informing practitioners and policy makers about interventions conducted as well as highlighting important areas for future research.

Study limitations

Limitations to our systematic mapping review should be noted when considering its findings. First, for the systematic mapping, general and broad search terms were applied to capture a wide range of relevant studies. A limitation related to this wide approach is that some specialized niches of research might be under-represented in the search results. The aim of this mapping review was to present the identified literature to provide an overview of the research field, this means that critical analysis of the included literature was out of the scope of this review.

While the literature searches generated a great amount of relevant literature, more publications probably also could have been identified by searching in other databases. Second, the summary of effects as well as the rest of the map provides an entry to further in-depth studies and should not be used as a basis for judgments whether the intervention categories are effective or evidence based. For such purposes, a comprehensive quality assessment of included research is required, as well as analyses that differentiate between populations, settings, context and other intervention characteristics, which was not done within this review.

Disclosure of potential conflicts of interest

The authors report no conflicts of interest.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

This study was initiated and funded by the Public Health Agency of Sweden.