Calls for evidence for violence prevention grew in the 1980s and 1990s, and over the ensuing years, evidence has played a more prominent role in decision making and program design for violence prevention. Workshop speaker Lisbeth Schorr from the Center for the Study of Social Policy noted that early in President Obama’s administration, the Office of Management and Budget started to increase the use of evidence in determining allocation of federal money. However, while increasing emphasis is being given to the evidence of violence prevention, workshop speaker Patrick Tolan from the University of Virginia noted there is limited consensus on the strength and type of evidence required to label programs as “evidence-based.” Workshop speakers discussed different types of evidence and methodologies for collecting evidence, and why building evidence for violence prevention is significantly important.
WHAT IS EVIDENCE?
Broadly speaking, evidence concerns facts (actual or asserted) that are known through experience and observation and intended for use in support of a conclusion (Lomas et al., 2005). In the context of the workshop discussions and this summary report, evidence typically refers to studies and evaluations that have been carried out to test the effects of programs, interventions, or policies on specific outcomes. The strength of evidence is considered to vary depending on the type of methods employed and how well the study was designed and executed. Workshop speakers debated the strengths and weaknesses of different types of methods for collecting
evidence for violence prevention. For measuring program effectiveness, workshop speaker Catherine Ward from the University of Cape Town suggested that randomized controlled trials (RCTs) are the gold standard, while other quasi-experimental studies are also highly informative. Creators of lists of best practices in violence prevention have established criteria for determining how to categorize programs that are based on the study methods used, the quality with which the methodology was executed, the number of studies conducted, and demonstrable positive effects. Although the standards vary among the different registries, in general, only evidence based on randomized or quasi-experimental designs is included.1
Workshop participant Peter Donnelly from the University of St. Andrews in Scotland added a note of caution, however, and suggested that the research community should refrain from automatically deferring to the RCT as the best method for generating evidence. He suggested that while an RCT can be highly effective for something like testing a new antibiotic, it is not necessarily the best way to understand complex public health interventions. Forum member and workshop speaker Michael Phillips from Shanghai Jiao Tong University School of Medicine expressed that the problem is not necessarily RCTs, but may be that the theoretical models on which they are based do not capture well the variables that affect phenomena in the violence prevention field.
Some workshop speakers warned against assuming that quantitative studies necessarily yield neutral results, given that the choice to study a particular indicator inherently gives increased value to that indicator and implies that its measurement will provide significant information. Many speakers discussed the importance of widening the knowledge base to include qualitative methods and data to inform the process of ascribing meaning to measurements and to provide a more comprehensive understanding of violence prevention. Schorr stressed that qualitative data are needed to inform decisions and give numbers meaning because 100 percent certainty is unattainable in the determination of complex, context-specific interventions. Workshop planning committee co-chair and Forum member James Mercy from the Centers for Disease Control and Prevention underscored the value of evidence gained from experiential knowledge that comes from on-the-ground practice and research. Workshop speaker Marta Santos Pais, Special Representative of the United Nations Secretary General on Violence Against Children, noted that victims themselves as well as their relatives and friends hold a wealth of potentially helpful information; however, finding and disseminating that information can be difficult.
1 See Part II of this report for detailed information on evidence-based registries for violence prevention.
The “Ideal” Evidence-Based Program
- Addresses major risk/protective factors that can be changed and substantially affect the problem
- Easy to implement with fidelity
- Rationale for and methods of services/treatments are consistent with the values of those who will implement
- Keyed to easily identified problems
- Inexpensive or positive cost/benefit ratios
- Can influence many lives or have life-saving types of effects on some lives
SOURCE: Tolan, 2013 (adapted from Shadish et al., 1991).
Drawing from his experience with the Blueprints for Healthy Youth Development, workshop speaker Patrick Tolan from the University of Virginia presented a list of characteristics of the ideal evidence-based program (see Box 2-1).
WHAT CAN WE LEARN FROM EVIDENCE?
Forum co-chair and workshop planning committee member Mark Rosenberg from the Task Force for Global Health suggested that the design of effective violence prevention interventions can be informed by four important questions. The questions are (1) What is the problem?, (2) What are the causes?, (3) What is effective?, and (4) How can it be scaled it up? Throughout the workshop, speakers elaborated on the ways in which evidence can be used to answer these questions.
The Magnitude of Violence
Surveillance studies, surveys, police reports, and other prevalence data can illuminate the magnitude of violence and its impacts. Forum co-chair and workshop speaker Jacquelyn Campbell from the Johns Hopkins School of Nursing referred to the December 2012 special issue of Lancet on the Global Burden of Disease Study, which showed how interpersonal violence and suicide rank against other causes of death in terms of mortality, and noted existing prevalence data that expose the problem and magnitude of violence.
Santos Pais discussed the potential for prevalence data to better expose the depth of violence—where it happens and whom it affects. She noted
that the most vulnerable populations and their problems are sometimes hidden and unnoticed by the public, and more can be done to develop tools to more thoroughly collect information on how violence impacts them. For example, she pointed out the invisibility of vulnerable children—including children who are too young to speak or seek support, are disabled, in detention, or are in situations of economic or political instability or crisis—and noted that it is difficult for children themselves to report their cases and tell their stories. Such vulnerabilities result in a vast underreporting of violence against children, especially in countries with few resources dedicated to prevalence studies.
As an example of a country-wide effort to collect such data, Santos Pais pointed to the Tanzanian National Survey of Violence Against Children, which illuminates the pervasive and widespread nature of violence in the country (United Republic of Tanzania, 2011). It created a public conversation about violence in Tanzania and sparked greater investments in implementation efforts such as raising awareness; mobilizing public support; identifying areas for changes in legislation, policies, and services; and developing a communications strategy focused on reaching out to young people.
The Causes of Violence and Value of Prevention
Several speakers discussed the value of research that focuses on determining the root causes of violence victimization or perpetration. Mary Lou Leary from the Department of Justice suggested that criminal justice responses to violence are not enough, but rather more effort on preventing the root causes that stem from problems in schools, homes, financial situations, and the environment is needed. Mark Bellis from Liverpool John Moores University supported this suggestion and described the financial value of investing in interventions that focus on root causes of problems rather than addressing violence after it occurs. Such interventions may include the Nurse–Family Partnership or school-based social and emotional learning programs. Santos Pais noted that if people invest in prevention of violent household incidents early in a child’s life, they can “break this cycle and, in fact, create an opportunity for non-violence to prevail.” Jerry Reed from the Education Development Center added that understanding the root causes of different types of violence could expose linkages and relationships among different types that can lead to more comprehensive approaches to prevention.
Effectiveness and Scalability of Interventions
Practitioners are faced with many challenges when implementing evidence-based programs in context-specific, often complex, environments. For a program to have population-level, long-term impacts, it often needs be scaled up and sustained. An emerging body of research on implementation science can help the violence prevention community build programs and services based on best practices. Information on context and culture can help practitioners determine how to best design their programs to address the needs of the target population when scaling up and implementing programs in new settings. (For more information on implementing interventions, see Chapter 5.)
WHY DO WE NEED EVIDENCE?
Workshop speakers provided several reasons why building, disseminating, and implementing evidence for violence prevention can contribute to a shared vision, efficiency for resource allocation, awareness of prevention, attention to social and cultural norms, and program improvement.
Establishing a Shared Vision
Rosenberg noted that violence prevention is not straightforward, and individuals and communities with a stake in the implementation of interventions have different priorities that influence their objectives. For example, when determining firearm access policies, communities have multiple objectives—trying to prevent firearm injuries and deaths while protecting individual rights. Evidence can help stakeholders to better understand the costs and benefits of certain interventions, and ultimately, as Santos Pais noted, help communities to develop a shared vision for violence prevention.
Resource and Program Efficiencies
Workshop speaker Neil Boothby from Columbia University noted that the violence prevention community has access to a limited amount of resources; thus, evidence can help determine the most efficient use of these resources. Santos Pais added that evidence can improve efficiencies in many aspects of program development, including planning, policy making, legislation, service provision, and ethical standards.
Building Awareness That Prevention Is Possible
Santos Pais stressed the need to convey to the public a sense of urgency to respond to violence. She challenged the audience to collect and present evidence in a way that makes violence prevention irresistible for everyone. Reed mentioned the need to talk about suicide in a way that will help individuals understand it and how it can be prevented, and instill hope in those who are struggling. Workshop speaker Daniela Ligiero of the Office of the U.S. Global AIDS Coordinator emphasized this point, adding that people need to understand that something can be done about violence—it is not a hopeless challenge. Then, Santos Pais noted, they will believe in the need to address violence and can mobilize and take action against it in their communities.
Shifting Social and Cultural Norms
Access to information and evidence could help shift social and cultural norms within communities. Santos Pais pointed out that certain forms of violence are accepted in some cultures, but, with expanded access to information on the effects of violence on individual and community well-being, these cultural and community norms may begin to change. In addition, evidence can inform perpetrators about nonviolent responses to conflict that may not be as widely used in their communities. For example, Santos Pais noted that some parents who physically punish their children may not be aware of other effective disciplinary methods, especially if they were physically punished as children themselves. Thus, information on effectiveness of other types of interventions and how to use them successfully could directly reduce violence in these circumstances.
Continual Program Improvement
Ligiero noted that, after implementing interventions, evaluation of programs and their impact is important if programs are to evolve and improve and, ultimately, reduce violence.
Key Messages Raised by Individual Speakers
- Although more evidence is needed to understand the effectiveness of interventions, evidence exists through prevalence data to call for action to prevent violence (Campbell).
- Evidence on root causes of violence can assist in the development of early interventions that can be more effective, comprehensive, and less costly (Bellis, Leary, Santos Pais, Reed).
- Understanding the effectiveness of violence prevention interventions may require multiple methods of data collection (Mercy, Schorr).
- Evidence can increase the effectiveness of interventions by contributing to a shared vision for program design and implementation, better resource allocation, increased awareness, shifts in social norms, and continued program improvement (Boothby, Ligiero, Santos Pais, Reed, Rosenberg).
Lomas, J., T. Culver, C. McCutcheon, L. McAuley, and S. Law. 2005. Conceptualizing and combining evidence for health system guidance. Ottawa, Ontario: Canadian Health Services Research Foundation.
Shadish, W., T. Cook, and L. C. Leviton. 1991. Foundations of program evaluation. New York: Sage.
Tolan, P. 2013. Creating lists of “evidence based” programs: Utilizing set standards for what works in violence prevention. Presented at the IOM Workshop on the Evidence for Violence Prevention Across the Lifespan and Around the World. Washington, DC, January 23.
United Republic of Tanzania. 2011. Violence against children in Tanzania: Findings of a national survey 2009. http://www.unicef.org/media/files/VIOLENCE_AGAINST_CHILDREN_IN_TANZANIA_REPORT.pdf (accessed July 1, 2013).