Evidence-Based Curriculum

The Hierarchy of Evidence is a way of ranking different types of information based on how reliable, trustworthy, and effective they are. Some types of evidence are stronger because they use careful methods, large amounts of data, and reduce bias, while others are weaker because they rely on small samples, observation, or opinion.

This hierarchy is important because it helps providers, programs, and practitioners make better decisions on what and how to implement interventions, curriculum, and tools depending on their populations and settings. By understanding which evidence is stronger, researchers, clinicians, and policymakers can place more confidence in conclusions that are based on high-quality studies and be more cautious with weaker evidence. In simple terms, it helps us separate what is most likely to be true and most effective from what is less reliable.

The Hierarchy of Evidence: Types and Categories

Let’s start with the basics. The primary types of evidence include the following, listed from highest to lowest strength:

Systematic Review – A systematic review comprehensively collects, evaluates, and synthesizes all relevant research on a specific practice, treatment, or intervention. Because it applies rigorous methods and critically appraises its sources, it is consistently ranked at the top of the evidence hierarchy.

Meta-Analysis – Often conducted as part of a systematic review, a meta-analysis statistically combines data from multiple studies. By aggregating results, it increases statistical power and produces conclusions that are more robust than those of individual studies. Its data-driven nature also helps reduce bias compared to purely observational research.

Randomized Controlled Trial (RCT) – RCTs are structured experiments in which participants are randomly assigned to receive one of two or more interventions. Randomization minimizes selection bias and other sources of error. Although often placed just below systematic reviews and meta-analyses, some hierarchies rank RCTs at the highest level.

Cohort Study – A cohort study is an observational design in which researchers follow a group of participants who share a common characteristic and compare outcomes with a group that does not share that characteristic. Researchers observe outcomes without intervening.

Case-Control Study – In a case-control study, researchers compare individuals who have experienced a specific outcome (cases) with those who have not (controls). The groups are examined for prior exposure to potential risk factors. A higher exposure rate among cases suggests an association.

Case Report – A case report provides a detailed description of a single patient or a small group, including symptoms, diagnosis, treatment, and outcomes. While considered lower-quality evidence due to limited sample size, case reports often serve as early indicators of emerging practices or effects.

Expert Opinion and Background Information – At the base of the evidence hierarchy are expert opinions and background sources. This category typically reflects professional consensus or guidelines issued by authoritative organizations rather than the views of a single individual.

 Facing Addiction in America: The Surgeon General’s Report on Alcohol, Drugs, and Health (2016)

“Well-supported scientific evidence shows that behavioral therapies can be effective in treating substance use disorders, but most evidence-based behavioral therapies are often implemented with limited fidelity and are under-used. Treatments using these evidence-based practices have shown better results than non-evidence-based treatments and services.”

Improving the Quality of Health Care for Mental and Substance-Use Conditions (Institute of Medicine (US), 2006)

“Despite substantial evidence documenting the efficacy of numerous treatments for mental and substance-use problems and illnesses, mental and/or substance-use (M/SU) health care (like all health care) often is not consistent with this evidence base. Further, in the absence of evidence on how best to treat some M/SU conditions, treatment for the same condition often varies inappropriately from provider to provider.”

Evidence-Based Practices for Substance Use Disorders (McGovern & Carroll, 2003)

“This article reviews current methods used to evaluate strength of the empirical evidence supporting the efficacy of specific therapies. These methods are drawn from the medical, psychological and substance use disorder treatment research fields.”

Evidence-Based Practices in Addiction Treatment: Review and Recommendations for Public Policy (Glasner-Edwards & Rawson, 2010)

“This article examines the concept of EBP, critically reviews criteria used to evaluate the evidence basis of interventions, and highlights the manner in which such criteria have been applied in the addictions field.”

Evidence-Based Addiction Treatment (Peter M. Miller, 2009)

“This volume is designed to provide both the student and the practicing clinician with a basic knowledge and understanding of current major evidence-based assessment and treatment methods. While the goal is to educate students and health professionals in the latest practice methodologies, the eventual aim is to improve the quality of care for addicted individuals and improve their lives.”

 From Cat's Cradle to Beat the Reaper: Getting Evidence-Based Treatments into Practice (Sorensen, 2011)

“To improve addiction treatment using evidence-based approaches we need develop a new cadre of forward-looking collaborating researchers and practitioners who address the issues of how to build an infrastructure that will maintain evidence-based approaches to care in the coming decades.”

Adoption of NIDA’s Evidence-Based Treatments in Real World Settings (NIDA, 2012)

“Comparison of the ‘Principles of Drug Addiction Treatment’ (NIDA 2009) with the results from the 2010 SAMHSA-generated survey of treatment centers (SAMHSA 2011) provides substantial evidence that translation of evidence-based treatments and treatment principles have not effectively penetrated the majority of treatment services.”

Strategies for Improving Fidelity in the National Evidence-Based Practices Project (Bond, et al, 2009)

“Conclusion: A multi-pronged implementation strategy was effective in achieving high fidelity in over half of the sites seeking to implement a new EBP. Strategies for implementing complex psychosocial EBPs require attention to many aspects of the implementation process.”

Enabling the Implementation of Evidence-Based Practice: A Conceptual Framework (Kitson et al, 1998)

“The paper offers a conceptual framework that considers this imbalance, showing how it might work in clarifying some of the theoretical positions and as a checklist for staff to assess what they need to do to successfully implement research into practice.”

 A simple scale of Gorski's warning signs for relapse (Miller & Harris, 2000)

“Though it has enjoyed widespread popularity, Gorski's post-acute withdrawal syndrome (PAWS) model of relapse has been subjected to little scientific scrutiny. A scale to operationalize Gorski's 37 warning signs was developed and tested in a larger prospective study of predictors of relapse. CONCLUSIONS: This scale of Gorski's warning signs appears to be a reliable and valid predictor of alcohol relapses.”

A randomized trial of early warning signs relapse prevention training in the treatment of alcohol dependence (Bennett, et al, 2005)

“This current pragmatic study aims to establish whether providing Gorski’s intervention to alcohol dependent people when they complete day treatment reduces their risk of drinking during the following year. The results justify the use of EWSRPT with similar patients being treated in similar services, when the aim is to minimise drinking.”

 Emotion regulation: Affective, cognitive, and social consequences (James J. Gross, 2002)

“One of life’s great challenges is successfully regulating emotions. Do some emotion regulation strategies have more to recommend them than others?”

“What seems likely to prove essential is having a rich palette of emotion regulatory response options that can be flexibly employed, with a clear appreciation of the relative costs and benefits of using any given regulatory strategy in a particular situation.”

Emotions in uniform: How nurses regulate emotion at work via emotional boundaries (Hayward and Tuckey, 2011)

“When an individual attends to an internally or externally psychologically relevant situation, the situation is appraised to imbue it with personal meaning and relevance. In turn, an emotion is initiated along with the cognitive, physiological, and behavioural response patterns typically associated with that emotion. However, emotions and their response patterns are not fixed. They can be manipulated to change the type, intensity, duration, and trajectory of emotions likely to be or being experienced.”

Acceptance and mindfulness-based therapy: New wave or old hat? (Hofmann and Asmundson, 2007)

“The objective of this article is to juxtapose these two treatment approaches [Cognitive Behavioral Therapy (CBT) and Acceptance and Commitment Therapy (ACT)], synthesize, and clarify the differences between them. The two treatment modalities can be placed within a larger context of the emotion regulation literature.”?

Ego Mechanisms of Defense and Personality Psychopathology (George E. Vaillant, 1994)

“It is often not just life stress but also a person's idiosyncratic response to life stress that leads to psychopathology. Thus, despite problems in reliability, the validity of defenses makes them a valuable diagnostic axis for understanding psychopathology. By including a patient's defensive style as part of the diagnostic formulation, the clinician is better able to comprehend what seems initially most unreasonable about the patient and to appreciate what is adaptive as well as maladaptive about the patient's defensive distortions of inner and outer reality.”

Adaptive Mental Mechanisms: Their Role in Positive Psychology (George E. Vaillant, 2000)

“In three ways, however, the involuntary defenses or coping processes are superior to voluntary coping processes. First, as I demonstrate in this article, involuntary defenses are independent of education and social privilege. Second, they can regulate people's perceptions of those internal and external realities that they are powerless to change. Third, the adaptive defenses can turn lead into gold. By this I mean such processes can serve as transformative agents in the real world.”

The Development of Defense Mechanisms (Phebe Cramer, 1991)

“The term ‘defense mechanism,’ as used in this article, refers to any cognitive operation that functions so as to protect the individual from the disruptive effects of excessive anxiety. In this sense, defenses are adaptive, they allow the individual to continue to function in anxiety-arousmg situations. When used excessively, defenses may distort reality.

This conception of defenses as a part of normal personality functioning opens the way for a consideration of the development of defense mechanisms. There is considerable consensus in the theoretical literature that some defenses are more primitive or immature, such as denial, repression, and negation, while others are more complex or mature such as intellectualization and identification”

Seven Pillars of Defense Mechanism Theory (Phebe Cramer, 2009)

“Among these unconscious processes are a group of mental operations referred to as defense mechanisms. These differ in the particular ways in which they function, but they all serve the same purpose – namely, to protect the individual from experiencing excessive anxiety, and to protect the self and self-esteem. Different from conscious coping strategies, these mechanisms operate at an unconscious level, so that the individual is unaware of how they function.”

“[W]e understand today that the use of defense mechanisms is also part of normal, everyday functioning. Used within limits, defenses aid us to manage stress, disappointment, and strong negative emotions. Only when used excessively are defenses likely to be linked with psychopathology.”

Recovery Capital as Prospective Predictor of Sustained Recovery, Life satisfaction and Stress among former poly-substance users (Laudet & White, 2008)

“This study builds on our previous cross-sectional findings that recovery capital (social supports, spirituality, religiousness, life meaning, and 12-step affiliation) enhances the ability to cope with stress and enhances life satisfaction.

Multiple regression findings generally supported the central hypothesis and suggested that different domains of recovery capital were salient at different recovery stages.”

The Potential of Recovery Capital (Best & Laudet)

“What is clear, however, is that the essence of recovery is a lived experience of improved life quality and a sense of empowerment; that the principles of recovery focus on the central ideas of hope, choice, freedom and aspiration that are experienced rather than diagnosed and occur in real life settings rather than in the rarefied atmosphere of clinical settings. Recovery is a process rather than an end state, with the goal being an ongoing quest for a better life.”

Universals in the Structure and Content of Values (Shalom H. Schwartz, 1992)

“This article discusses work that is part of a larger project intended to explore the importance of values in a wide variety of contexts. The project addresses three broad questions about values. First, how are the value priorities of individuals affected by their social experiences?… Second, how do the value priorities held by individuals affect their behavioral orientations and choices?… Third, the project addresses the question of cross-cultural or cross-national differences in value priorities and seeks to identify some of their causes and effects.”

An Overview of the Schwartz Theory of Basic Values (Shalom H. Schwartz, 2012)

“This article presents an overview of the Schwartz theory of basic human values. It discusses the nature of values and spells out the features that are common to all values and what distinguishes one value from another. The theory identifies ten basic personal values that are recognized across cultures and explains where they come from. At the heart of the theory is the idea that values form a circular structure that reflects the motivations each value expresses. This circular structure, that captures the conflicts and compatibility among the ten values is apparently culturally universal. The article elucidates the psychological principles that give rise to it.”

Self-Affirmation: Understanding the Effects (David K. Sherman, 2013)

“Across a wide variety of threats and stressful, identity-threatening situations, values affirmations attenuated defensiveness, reduced physiological stress responses, and facilitated academic performance among students experiencing identity threats. The effects of the social psychological manipulations fostered, in some cases, lasting changes.”

“Value affirming activities encourage people to reflect on and express important, core aspects of the self. The first proposition, then, is that values affirmations boost selfresources, that is, the psychological resources that people have to cope with threats.”