What is positive youth development and how might it reduce substance use and violence? A systematic review and synthesis of theoretical literature

Abstract

Background:
Preventing adolescent substance use and youth violence are public health priorities. Positive youth development interventions are widely deployed often with the aim of preventing both. However, the theorised mechanisms by which PYD is intended to reduce substance use and violence are not clear and existing evaluated interventions are under-theorised. Using innovative methods, we systematically searched for and synthesised published theoretical literature describing what is meant by positive youth development and how it might reduce substance use and violence, as part of a broader systematic review examining process and outcomes of PYD interventions.

Methods:
We searched 19 electronic databases, review topic websites, and contacted experts between October 2013 and January 2014. We included studies written in English, published since 1985 that reported a theory of change for positive youth development focused on prevention of smoking, alcohol consumption, drug use or violence in out-of-school settings. Studies were independently coded and quality-assessed by two reviewers.

Results:
We identified 16 studies that met our inclusion criteria. Our synthesis suggests that positive youth development aims to provide youth with affective relationships and diverse experiences which enable their development of intentional self-regulation and multiple positive assets. These in turn buffer against or compensate for involvement in substance use and violence. Existing literature is not clear on how intentional self-regulation is developed and which specific positive assets buffer against substance use or violence.

Conclusions:
Our synthesis provides: an example of a rigorous systematic synthesis of theory literature innovatively applying methods of qualitative synthesis to theoretical literature; a clearer understanding of how PYD might reduce substance use and violence to inform future interventions and empirical evaluations.

Full text

R E S E A R C H A R T I C L E Open Access
What is positive youth development
and how might it reduce substance use
and violence? A systematic review and
synthesis of theoretical literature
Chris Bonell
1*
, Kate Hinds
1
, Kelly Dickson
1
, James Thomas
1
, Adam Fletcher
2
, Simon Murphy
2
,
G. J. Melendez-Torres
3
, Carys Bonell
4
and Rona Campbell
5
Abstract
Background: Preventing adolescent substance use and youth violence are public health priorities. Positive youth
development interventions are widely deployed often with the aim of preventing both. However, the theorised
mechanisms by which PYD is intended to reduce substance use and violence are not clear and existing evaluated
interventions are under-theorised. Using innovative methods, we systematically searched for and synthesised published
theoretical literature describing what is meant by positive youth development and how it might reduce substance use
and violence, as part of a broader systematic review examining process and outcomes of PYD interventions.
Methods: We searched 19 electronic databases, review topic websites, and contacted experts between October
2013 and January 2014. We included studies written in English, published since 1985 that reported a theory of
change for positive youth development focused on prevention of smoking, alcohol consumption, drug use or
violence in out-of-school settings. Studies were independently coded and quality-assessed by two reviewers.
Results: We identified 16 studies that met our inclusion criteria. Our synthesis suggests that positive youth development
aims to provide youth with affective relationships and diverse experiences which enable their development of intentional
self-regulation and multiple positive assets. These in turn buffer against or compensate for involvement in substance use
and violence. Existing literature is not clear on how intentional self-regulation is developed and which specific positive
assets buffer against substance use or violence.
Conclusions: Our synthesis provides: an example of a rigorous systematic synthesis of theory literature innovatively
applying methods of qualitative synthesis to theoretical literature; a clearer understanding of how PYD might reduce
substance use and violence to inform future interventions and empirical evaluations.
Keywords: Theory of change, Positive youth development, Smoking, Alcohol, Drugs, Violence
Background
Adolescent use of tobacco, alcohol and drugs (henceforth
termed substance use) is an important threat to public
health leading to later-life chronic disease [1, 2]. Surveys
suggest that a fifth of US adolescents nearing the end of
high school engaged in binge drinking in the last month
[3]. Around a quarter of US adolescents in the second year
of high school report illicit drug use in the last year [4].
Use of substances such as tobacco and illicit drugs is sub-
ject to social determinants acting at the individual, peer,
family and community level, with important implications
for health inequalities [5]. Preventing youth violence is an-
other public health priority [6–8]. A quarter of UK youth
age 15–16 years have carried a weapon and a fifth report
attacking someone with intent to hurt them seriously [9].
Violence is subject to marked inequalities [10] and is asso-
ciated with increased risk of: physical health problems;
* Correspondence: c.bonell@ioe.ac.uk
1
Department of Childhood, Families and Health, University College London
Institute of Education, 18 Woburn Square, WC1H 0NR London, UK
Full list of author information is available at the end of the article
© 2016 Bonell et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Bonell et al. BMC Public Health (2016) 16:135
DOI 10.1186/s12889-016-2817-3
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[11] engaging in other health risk behaviours such as sub-
stance use; [12–14] long-term emotional, behavioural and
mental health problems; [11, 15, 16] and self-harm and sui-
cide [17]. The economic costs associated with youth sub-
stance use and aggression are extremely high [18–20].
There are increasing calls for youth interventions to
address multiple risk behaviours since such behaviours
cluster together, [21, 22] and because combined interven-
tions are potentially more efficient [23]. Positive youth
development (PYD) is one such intervention. In the UK,
PYD has been defined as voluntary educational activities
aiming to promote generalised positive development, in
terms of skills, attitudes, relationships and identities,
rather than merely preventing problem behaviours [24]. In
the USA, PYD has been defined as voluntary education
outside school hours aiming to promote generalised
(not just health) and positive (not just avoiding risk) de-
velopment of assets such as bonding, resilience, social,
emotional, cognitive, behaviour or moral competence,
self-determination, spirituality, self-efficacy, clear and
positive identity, belief in the future, recognition for
positive behaviour, opportunities for pro-social involve-
ment and/or pro-social norms [24, 25]. Interventions
are said to qualify as PYD if they address multiple as-
sets or a single asset applied to multiple domains such
as the family or local community [25].
PYD interventions are widely deployed, [26] often with
the aim of preventing substance use and violence [27, 28].
Existing reviews suggest PYD can reduce violence and
drug use albeit with considerable heterogeneity of effects,
[29, 30] but these reviews vary in how systematic they are,
and are becoming out of date. A more recent review
focused only on school extra-curricular interventions
reported a significant effect reducing problem behaviours
but not drug use [31]. Each of these reviews focused exclu-
sively on empirical evidence for intervention effectiveness.
However, empirical studies of the effectiveness of par-
ticular interventions are insufficient to tell us whether the
PYD approach is effective unless we are clear what theory
of change this approach involves and whether particular
interventions embody it. What is needed is a theory of
change defining what PYD interventions involve and the
intended causal mechanisms via which they are intended
to reduce substance use and violence. This would help
determine whether existing intervention studies provide
evidence about the effectiveness of the PYD approach or
not. It could also inform the design of future PYD inter-
vention studies so that they provide evidence about the ef-
fectiveness not only of the specific intervention in question
but on the overall PYD approach. However, no existing
systematic review has synthesised PYD theories of change.
The synthesis of empirical evaluations of PYD inter-
ventions also performed as part of this overall review
tobepublishedshortlyfoundthatincludedempirical
evaluations assessed under-theorised interventions and
so provide little guidance on the effectiveness or otherwise
of the PYD approach. A synthesis of the theoretical litera-
ture could thus make an important contribution to im-
proving the quality of PYD interventions being evaluated
and thus of the evidence base for this approach.
Therefore, as part of a broad review also examining
empirical evidence, we undertook a systematic review to
examine theoretical literature on the PYD approach to
preventing substance use and violence. As mentioned
above, our synthesis of the empirical evidence will be
published in due course.
Increasing interest in theory synthesis reflects growing
recognition of the importance of understanding mecha-
nisms in intervention research [27, 28, 32]. Theory synthe-
sis differs from meta-theory in aiming to compare and
integrate closely related theories [28]. This best describes
our own goal in synthesising a relatively cohesive PYD the-
oretical literature united by its use of the term ‘positive
youth development’and focus on how such interventions
might reduce violence and substance use. Our aims were
first to develop a clearer normative understanding of what
is meant by PYD in terms of its goals. Second, we aimed to
develop a comprehensive causal theory of change for how
PYD might prevent substance use and violence.
Methods
Methods were determined a priori, described in a protocol,
[33] and followed PRISMA guidance [34] (See Additional
file 1. Studies were included in the overall review if they:
were published since 1985; were in English; focused on
youth age 11–18 years; focused on PYD as defined in our
introduction; reported a theory of change, process evalu-
ation or experimental/quasi-experimental outcome evalu-
ation; and focused on prevention of smoking, alcohol
consumption, drug use or violence in out-of-school set-
tings. Reports included in the theory synthesis were re-
quired to describe what PYD involves and how it is
intended to reduce substance use or violence.
We searched 19 bibliographic databases, including Psy-
cINFO, MEDLINE and ERIC, plus topic-specific websites,
trials registers and experts between October 2013 and
January 2014. For a complete list of sources and approach
to searching refer to the published protocol [33]. http://
www.crd.york.ac.uk/prospero/display_record.as-
p?ID=CRD42013005439). We used indexed and free-text
terms related to population (for example, youth) AND
intervention (for example, informal education) OR popu-
lation/intervention (for example, youth work). An ex-
ample is provided in Additional file 2. References were
initially screened on title/abstract then full report if the
title or abstract suggested relevance or provided in-
sufficient information to judge. At both stages,
screening was initially done by pairs of researchers
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assessing batches of the same 100 references, moving
to single screening once 90 % agreement was
achieved.
We extracted data on: aim; description of theory;
and links to other theories. Data-extraction tools were
piloted on two studies with reviewers meeting to
identify differences and refinements. All reports were
then extracted by two reviewers who then discussed
and agreed coding. Unlike most theory syntheses,
[35–37] we aimed to assess study quality and use this
to determine which studies were given most weight in
our synthesis. Study quality was assessed by pairs of
reviewers (from CB, KH, JT) independently, using a
new tool informed by a previous review [27] and
methodological work [38, 39]. Quality was assessed in
terms of: construct clarity; clarity of relationships be-
tween constructs; empirical testability; parsimony; and
potential generalisability. Reviewers were provided
with guidance to inform decisions. Reviewers settled
differences through discussion.
We aimed to synthesise theoretical literature. To do
so, we innovatively applied methods previously applied
to synthesising qualitative research [40]. We used a form
of qualitative analysis known as template analysis [41].
Reviewers first developed an a priori template which in-
cluded PYD theoretical constructs already known to us
(Table 1). The two reviewers independently used this
template to code two theory papers (chosen on the basis
that both reviewers had assessed these as high quality),
refining the theoretical constructs within template in the
light of their reading of these papers and writing
‘memos’to explain their rationales for doing so. The re-
viewers then discussed their refined templates,
developing an agreed version. The two reviewers then
coded the remaining theory papers, further refining the
coding template as they went along and drafting an
overall memo explaining their refinements and summar-
ising their emerging overall synthesis. Reviewers kept a
record of the coding template and their overall memo as
it stood at the end of coding each paper. At the end, the
reviewers compared and combined their memos to pro-
duce an overall summary of their analysis.
Results
The searches provided 32,394 unique references, of
which 16 reports [30, 42–56] met the inclusion criteria
for the theory synthesis (see Fig. 1), described in Table 2.
One report originated from Canada [47] and one from
Hong Kong [52] while the remainder were from the
USA [30, 42–46, 48–51, 53–56]. One also reported a
process and outcome evaluation [46]. Most referred to
established theories, such as ecological systems theory,
[42] social learning theory, [46] and identity develop-
ment theory [47] in setting out a theoretical basis for
PYD preventing substance use and violence. Although
all studies described what is meant by PYD and offered
some insights into how PYD might reduce violence or
substance use, only nine studies addressed mechanisms
in depth [30, 44, 46, 48, 50–52, 55, 56].
The two reviewers produced independent quality scores
for each report but found the criteria difficult to apply
(Table 3) and could agree a common score for only three
studies. We therefore decided to include theory reports in
our synthesis regardless of quality.
Despite variation in what aspects of the potential causal
pathway studies examined, these did not contradict each
other and were sufficiently complementary to enable an
overall synthesis to be developed. The syntheses produced
by each reviewer differed. Both reviewers judged that
many included reports did not on their own describe a
comprehensive theory of change for how PYD might re-
duce substance use and violence, some for example focus-
ing on particular sub-sections of the causal chain. One
reviewer concentrated her synthesis on normative theory
about PYD goals. The other developed a synthesis of nor-
mative and causal theory, finding that the normative the-
ory was helpful in piecing together a rather fragmentary
literature to develop a more comprehensive theory of
change (Fig. 2). Because two reviewers synthesised in par-
allel, these differences in approach were transparent and
could be used to provide depth and breadth to the review.
The following themes were apparent:
Normative theory of PYD
A major theme in the literature was what are the under-
lying goals of PYD programmes. These focused on the need
to increase young people’s assets and ability to thrive, by
Table 1 Initial coding template
Themes Codes and sub codes
Definition of PYD
interventions
PYD versus prevention science/traditional
youth programmes
Definition in terms of developmental
assets versus programme atmosphere
Characteristics of programmes
Taxonomy Individual versus environment/community
emphasis
Pro-social development versus critical
conscious raising
General ‘pile up’of assets versus specific
‘molecular’effects of specific assets on
specific outcomes
Mechanism of action Action on risk of SU/violence
Action on thriving
Possible moderation
by context
Moderation by person/population
Moderation by setting
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developing affective relationship with providers and engage-
ment in a diverse range of activities offered by PYD
programmes.
Thriving and positive assets
The major emphasis across nearly all the literature was on
the importance of enabling young people not merely to
avoid risk behaviours but to achieve “normal development”
(Roth and Brooks-Gunn [30] p.172). Kim et al. [51],
Catalano et al. [48], Busseri et al. [47] and Roth and
Brooks-Gunn [30] for example all state that “problem free is
not fully prepared”(Roth and Brooks-Gunn [30] p.170).
Lerner and Lerner [53] and Kim et al. [51] all contrast PYD
with prevention science, arguing that PYD aims to develop
various positive assets rather than simply focusing on pre-
venting risk behaviours. PYD is described as a “strength-
based approach”(p.781):
“The theory and research undergirding developmental
assets …aredesigned,inpart,toreframethetargetsand
pathways of human development around images of
strength and potential. We posit that this shift is crucial
for mobilizing both personal and collective efficacy on
behalf of child and adolescent development.”
Roth and Brooks-Gunn [30], Busseri et al. [47], Lerner et
al. [53, 54], Schwartz et al. [56] and Perkins et al. [55] all
build on this idea of thriving by suggesting what particular
assets PYD might aim to develop, terming these the “5
Competences”:
“(1) competence in academics, social, emotional, and
vocational areas;
(2) confidence in who one is becoming (identity);
(3) connection to self and others;
(4) character that comes from positive values, integrity,
and a strong sense of morals;
(5) caring and compassion”(Perkins et al. [55] p.50).
Benson et al. [42, 43, 45] and Roth and Brooks-Gunn
[30] propose an alternative categorisation of 40 assets
Fig. 1 Screening
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Table 2 Characteristics of theory reports
Author and title Stated aims Existing theories cited
Benson et al. [19] Youth development,
developmental assets, and public policy
1. Describes the strength-based youth
development approach by comparing
it to and contrasting it with the deficit-based
orientation to successful development.
2. Discusses the theoretical and empirical basis
of the developmental asset framework as a prime
exemplar of positive youth development, a
comprehensive conceptualization of developmental
well-being, and a generator of knowledge regarding
the developmental pathways of young people.
3. Identifies relevant social and cultural dynamics
affecting youth, considers their implication for
youth development policy, and highlights a
number of public policies from around the
country that reflect the tenets and unfolding
wisdom of healthy youth development.
4. Assessing the socio-political prospects for
developmental principles and knowledge to
actually inform and shape public policy for
young people.
Ecological model of human development
Benson [18] Developmental assets:
an overview of theory, research
and practice
1. Discusses the concepts of developmental
assets, asset building communities and asset
building society.
2. Discusses the 4-H survey in relation to
assets and damaging behaviours.
Developmental systems theory
Action theory of development
Ecological model of human development
Benson [20] Positive youth development
and the prevention of youth aggression
and violence
1. Reports analyses on several databases of
6th-12th grade students in the United States,
to explore the linkage of positive relationships,
opportunities, skills, and values, called
Developmental Assets, to prevention of youth
aggressive and violent behaviours.
Ecological Theory
Benson et al. [21] The contribution of
the developmental assets framework to
positive youth development theory
and practice
1. Synthesises literature on developmental assets.
2. Discusses the recent development of: the
Developmental Asset Profile, an instrument
designed, in part, to assess change-over-time;
the utilization of asset measures in international
research; the expansion of the assets framework
to early childhood and young adults; and new
research using latent class analysis (LCA) to
identify classes or subgroups of youth.
-
Berg et al. [22] Youth Action Research
for Prevention: a multi-level intervention
designed to increase
efficacy and empowerment
among urban youth
1. Reports on the theory of change for and
empirical evaluation of the Youth Action
Research for Prevention program.
Ecological systems theory
Identity theory
Social learning theory
Social construction theory
Critical Transformational Theories
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Table 2 Characteristics of theory reports (Continued)
Busseri et al. [23] Breadth and intensity:
salient, separable, and developmentally
significant dimensions of structured
youth activity involvement
1. Presents a theory-based framework for
studying structured activity involvement (SAI)
as a context for positive youth development
based on two key dimensions: breadth and
intensity of involvement.
2. Demonstrates the separatability, salience,
and developmental significance of these
two dimensions.
Identity development theory
Life-span development processes of selective
optimization with compensation
Concept of ‘affordances’in Gibson’secological
theory of human perception
Catalano et al. [24] Prevention science
and positive youth development:
competitive or cooperative frameworks?
1. Examines the convergence in the critiques
and recommendations for the future of
programs to promote healthy development
and prevent problem behaviors among
children and adolescents.
Attachment theory
Identity development theory
Ecological model of human development
Ginwright and Cammarota [25]
New Terrain in Youth Development:
The Promise of a Social Justice Approach.
1. Presents a youth development model that
addresses structures of power and teaches
youth to understand how their opportunities
are circumscribed by larger political, economic,
and social forces.
2. Critiques two dominant approaches to youth
development which have oppressed urban
youth of colour.
Critical consciousness theory
Kia-Keating et al. [26] Protecting and promoting:
an integrative conceptual model for healthy
development of adolescents
1. Draws on extant research to delineate linkages
between the risk and resilience and positive
youth development literatures.
-
Kim et al. [27] Toward a new paradigm in
substance abuse and other problem behavior
prevention for youth: youth development
and empowerment approach
1. Addresses a paradigm shift taking place in
the field of substance abuse prevention
directed for youth.
2. Introduces an innovative approach to
substance abuse and other problem
behaviour prevention that reflects
this shift in prevention paradigm.
Social control theory
Social learning theory
Social development model
Problem behavior theory
Expectations-states theory
Lee [28] Construction of an integrated
positive youth development conceptual
framework for the prevention of the use
of psychotropic drugs among adolescents
1. Constructs an integrated conceptual framework
for the prevention of adolescents’use and
abuse of psychotropic drugs.
2. Provides empirical support for integrating a
positive youth development perspective in
the revised model.
Social learning theory
Symbolic interaction theory
Operant conditioning theory
Lerner and Lerner [29] Toward a New Vision
and Vocabulary About Adolescence: Theoretical,
Empirical, and Applied Bases of a ‘Positive Youth
Development’Perspective
Sets out a new vision and vocabulary about
adolescence in terms of theoretical, empirical,
and applied bases of a ‘positive youth
development’perspective.
Developmental systems theory
Lerner et al. [30] Individual and contextual
bases of thriving in adolescence: a view of
the issues
1. Describes the relational developmental systems
theory-based, positive youth development (PYD)
perspective that frames much of contemporary
research about health and positive development
across the adolescent period and that, more
specifically, frames the 4-H Study of PYD.
Bioecological theory
Action theory models of intentional,
goal-directed behaviours
Life-course theory
Dynamic systems theory
Holistic person-context interaction theory
Developmental systems formulations
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Table 2 Characteristics of theory reports (Continued)
Perkins et al. [31] Community Youth
Development: A Partnership for Action
1. Introduces the concept of Community Youth Development. -
Roth and Brooks-Gunn [12] Youth
development programs: risk,
prevention and policy
1. Focuses on the promise and reality of youth
development programs.
2. Reviews the available evidence about
program effectiveness.
3. Defines the elements of youth development
programs based on theoretical writings and
ethnographic studies.
4. Investigates the reality in two ways, by
mapping the defining principles of youth
development to practice by looking at
which elements are present in successful
programs, and by investigating the relation
between these elements and program outcomes.
-
Schwartz et al. [32] Addressing the
challenges and opportunities for
today’s youth: toward an integrative
model and its implications for research
and intervention.
1. Calls for, and proposes some tenets of, model
building in adolescent psychosocial development.
2. Suggests that there is a need for a model that
draws from the risk-protection approach, from
which many prevention science approaches are
drawn, and the applied developmental science
perspective, from which many positive youth
development approaches are drawn.
Selection, Optimization and Compensation Model
Theory of planned behaviour
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which, though similar to the above list, divide up between
internal assets possessed by individuals and external assets
possessed of environments which should nurture positive
development.
Affective relationships with adults
Several authors, such as Roth and Brooks-Gunn [30],
Benson and Scales, [44] Lerner and Lerner [53] and Kim
et al. [51] argue that PYD interventions should involve
providers developing affective (sustained, supportive and
emotionally expressive) relationships with young people.
They contrast these with provider-client relationships in
conventional youth services which tend to be more
narrowly instrumental (focused on providing specific ser-
vices such as education or careers advice). It is argued that
PYD providers should create a “family-like atmosphere”
[30] (p.172) characterised by enduring and emotionally
engaged relationships.
Diverse activities and settings
Many of the included reports assert that PYD interven-
tions should offer diverse activities and settings for par-
ticipants. Lerner and Lerner [53] and Benson et al.
suggest that such diversity enables young people to
develop broad skills. Such activities provide multiple
opportunities for recognition [30]. Benson et al. suggest
that PYD activities should involve “synergies”and “re-
dundancies”(p.210). In other words, PYD interventions
should provide young people with opportunities to de-
velop the same assets in the course of different activities,
so that these mutually reinforce each other.
Causal theory of PYD
Another major theme in the literature was that PYD
programmes can promote positive development by in-
stilling young people with an ability for intentional self-
regulation. A final theme was how the development of
intentional self-regulation and of positive assets protects
young people from engagement in risk behaviours such
as substance use and violence.
Intentional self-regulation
Busseri et al. [47], Schwartz et al. [56] and Lerner et al.
[54] all suggest that PYD helps young people develop
capacities for ‘intentional self-regulation’:
“intentional self regulation may involve the selection
of positive goals (e.g., choosing goals that reflect
important life purposes), using cognitive and
behavioral skills (such as executive functioning or
Table 3 Quality assessment of theory studies
Paper Clarity of constructs Clarity of relationship between constructs Testability Parsimony Generalisability Total score
CB/JT KH CB/JT KH CB/JT KH CB/JT KH CB/JT KH CB/JT KH
Benson et al. [19] 0 0.5 0 0.5 0 0 0 0 1 1 1 2
Benson [18] 0 0.5 1 0 1 0 0 0 1 0 3 0.5
Benson et al. [20] 1 0 0.5 0 1 0 0 0 1 1 3.5 1
Benson et al. [21] 0 1 0 0.5 1 1 0 0 1 1 2 3.5
Berg et al. [22]010 1 01011115
Busseri et al. [23] 1 1 0.5 1 1 1 1 1 1 1 4.5 5
Catalano et al. [24] 0.5 0.5 0.5 0.5 1 0 1 0 1 1 4 2
Ginwright and Cammarota [25]0 0 1 0 0 0 1 0 1 0 3 0
Kia-Keating et al. [26]010 1 10011124
Kim et al. [27]111 111111155
Lee [28] 0 0 0 0.5 0 0 0 0 1 1 1 1.5
Lerner and Lerner [29] 1 0.5 0.5 1 1 1 1 1 1 1 4.5 4.5
Lerner et al. [30] 1 0 1 0.5 1 0 1 0 1 1 5 1.5
Perkins et al. [31]101 0 00001131
Roth and Brooks-Gunn [12]1 1 1 0 001 11 14 3
Schwartz et al. [32]101 0 10101050
These scores were agreed between KH and JT
Ginwright and Cammarota [25]0 0 0 1 1 2
Perkins et al. [31]1 1 0013
Roth and Brooks-Gunn [12]1 1 0 1 1 4
Key: 1 = Yes, 0.5 = Partial, 0 = No
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resource recruitment) to optimize the chances of
actualizing ones purposes and, when goals are
blocked or when initial attempts at optimization
fail, possessing the capacity to compensate
effectively”. (Lerner et al. [54] p.1108)
PYD can help adolescents reflect on existing behav-
iour, select personal goals and activities through which
to pursue these, and apply available resources to pursue
these goals and activities [42].
Lerner et al. [54] suggest that by promoting young
people’s ability to intentionally self-regulate, PYD promotes
positive interactions between individuals and their environ-
ments (or ‘developmental regulations’), to occur whereby
young people are better able to capitalise on opportunities
present within their environments in order to develop
more and more positive assets of the sorts listed earlier
(Lerner et al. [54]; Benson [42]; Busseri et al. [47]; Schwartz
et al. [56]).
However, these authors are not explicit about how PYD
interventions actually enable young people to develop
their capacity for intentional self-regulation. For example,
Benson [42] only offers generalities such as the suggestion
that PYD does this by:
“[i]ncreasing the developmental attentiveness of
contexts…to increase their capacity to nurture,
support, and constructively challenge the developing
person, …[e]nhancing the skills and competencies of
youth (to further enable their “natural”capacity to
engage with, connect, change, and learn from their
social contexts…[and [c]reating processes and
opportunities to invite youth to actively exercise and
utilize their capacity to engage with and change their
social contexts”(p.39).
How PYD might promote intentional self-regulation
This quote, as well as the theoretical literature more
generally, stops short of explaining exactly how PYD
programmes might promote better intentional self-
regulation. However, informed by our earlier synthesis of
PYD’s normative theory, we might fill in the gaps. First,
PYD might provide individuals with the resources, in the
form of relationships and training in specific skills which
are the critical inputs upon which the use of intentional
self-regulation within specific intervention-related activ-
ities depends. Second, PYD might enable individuals to
practice intentional self-regulation in the context of mul-
tiple activities and settings so that they improve their gen-
eral ability to intentionally self-regulate. Busseri et al. [47]
come closest to making this explicit. They argue that PYD
can provide a range of “affordances”(p.907) resources
individuals use in the course of their development (e.g. re-
lationships, challenges, education) to which young people
may respond. Different individuals at different points in
their maturation, with different needs and goals, will make
use of different affordances. Third, PYD might refocus in-
dividuals’existing capacities for intentional self-regulation
away from anti-social goals and towards pro-social goals.
This might occur via rewarding young people when they
Fig. 2 Synthesised theory of change for PYD effects on substance
use and violence
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abandon anti-social activities and engage in specific pro-
social activities. Kim et al. [51] for example refer to social
learning theory to suggest that, by providing positive ex-
amples and celebrating achievements in the realm of pro-
social activities, PYD programmes can reinforce positive
behaviours and bonds to conventional society.
How PYD might reduce risk behaviours
The way in which PYD might reduce risk behaviours, such
as substance use and violence, was a relatively minor
theme in the literature, a limitation acknowledged by
Kia-Keating et al. [50] and Lerner et al. [54]. The PYD lit-
erature offers a number of general suggestions about how
the development of positive assets might reduce risks as
well as a few isolated examples of how specific assets might
protect against risk, but stops short of offering a compre-
hensive theory of change for how PYD reduces risk.
Buffering and compensation
Positive assets might reduce risk by processes of ‘buffering’
(Catalano et al. [48] p.233; Kia-Keating et al. [50]) or
“compensation”(Busseri et al. [47] p.912). N.B. this use of
the term ‘compensation’differs from that cited above to
describe one of the stages of intentional self-regulation.
Buffering is described as a process whereby risk factors
in the environment have less influence on the behaviour
of those with positive assets than those who lack these
assets [48]. For example, individuals possessing the asset
of a positive sense of identity might be less prone to peer
pressure to engage in risk behaviours (Catalano et al.
[48]; p.232).
Catalano et al. [48] describe ‘compensation’in terms of
those possessing positive assets being able to engage in
risk with less harmful consequences. For example, a young
person who is engaged with school might still participate
in violence but with fewer harmful developmental effects.
Schwartz et al. [56] refer to similar processes using slightly
different terminology.
Pile-up and molecular impacts on risk
Pile-up is defined as occurring when the general accumula-
tion of multiple assets regardless of their particular charac-
teristics might lead to reduced risk behaviours. In contrast,
molecular mechanisms occur when specific assets bring
about reductions in risk behaviours because of their par-
ticular characteristics.
Other authors offer examples of assets which offer mo-
lecular protection against risk behaviors. Kim et al. [51]
suggest that engagement with pro-social institutions will
lead to reductions in anti-social behaviours. Benson and
Scales [44] suggest that social skills, connections with pro-
social peers and engagement with school will reduce in-
volvement in substance use and violence via young people
resolving conflict, modelling responsible behaviours and
being reluctant to defy pro-social norms. Kia-Keating et
al. [50] suggest that: social integration and self-efficacy will
offer protection against conduct problems; pro-social be-
haviours will protect against substance use; emotional
self-regulation will protect against externalising problem
behaviours; adult supervision will protect against delin-
quency; and self-efficacy can interact with parental moni-
toring to protect against alcohol use. However these are
piecemeal suggestions rather than a comprehensive theory
of change.
Discussion
Summary of main results
Sixteen reports were included. All described PYD goals.
All offered some insights into how PYD might reduce
substance use and violence but none provided a compre-
hensive theory of change for how PYD might reduce sub-
stance use and violence. Different reports focused on
different parts of the pathway by which PYD might prevent
substance use and violence: some focusing on intentional
self-regulation, some on the development of multiple, posi-
tive assets and some on how such assets might reduce risk
behaviours. However, in doing so reports did not contra-
dict each other and this enabled us to develop a more
comprehensive theory of the overall pathway by which
PYD might prevent substance use and violence, described
below and summarised in Fig. 2.
Overall PYD interventions aim to provide young people
with: positive expectations; enduring, affective relation-
ships with adults; and diverse activities and settings. Par-
ticipants learn ‘intentional self-regulation’, which involves:
reflecting on existing behaviour; selecting personal goals
and activities through which to pursue these; and using
available resources to pursue these goals and activities.
PYD interventions enable young people to learn and be
rewarded for intentional self-regulation applied to mul-
tiple, mutually reinforcing intervention activities such as
sports or arts. This then enables them to develop and
apply intentional self-regulation more generally to other
pro-social goals. As a result of developing intentional self-
regulation, young people are better able to develop various
positive assets (for example, the 5 C’s: competence, confi-
dence, connection, character and caring). As these accrue,
young people can make increasingly better use of the op-
portunities available in their wider environment. This en-
ables further accrual of assets and ultimately young people
contributing positively to their communities and societies,
either maintaining or challenging existing arrangements.
These positive assets may then reduce risk behaviours via
‘buffering’, whereby environmental risk factors are less
influential, or ‘compensation’, whereby young people still
engage in risk behaviours but with fewer adverse
consequences. Positive assets may reduce risk ‘molecularly’
(a specific asset offers protection against a specific risk), or
Bonell et al. BMC Public Health (2016) 16:135 Page 10 of 13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.

via ‘pile-up’(accumulation of multiple assets is generically
protective). Molecular protection might occur for example
when engagement with pro-social peer groups or institu-
tions reduces anti-social behaviours, and when improved
emotional self-regulation, social skills and self-efficacy
enable better decision-making. The PYD theoretical litera-
ture however does not offer a comprehensive theory of
change for which positive assets help prevent substance use
or violence.
Limitations
The main limitation of our review was in the assessment
of quality. Unlike most theory syntheses, [35–37] we
aimed to do this in order to give more weight in our
synthesis to high-quality studies. Despite being informed
by previous work [38, 57] and being accompanied by
guidance, our criteria could not be applied consistently.
If quality criteria are to be used in future syntheses of
theoretical literature then more guidance is required on
assessing these, particularly testability and parsimony.
There were also limitations in included reports. Al-
though 16 reports is a good number for a review of theory,
only nine of these provided a detailed consideration of
how PYD might prevent risk behaviours. Much of the lit-
erature focused on asserting the normative value of PYD
and consideration of causal theory was sometimes periph-
eral and unsystematic. Included reports failed to explain
how PYD interventions aim to optimise young people’s
capacity for intentional self-regulation or comprehensively
explain how promoting positive assets could reduce risk
behaviours. We nonetheless synthesised a theory of
change by bringing together fragments from multiple re-
ports. Our synthesis would have been less comprehensive
had we only synthesised theoretical literature judged to be
of high quality.
Conclusions
This paper is an example of a rigorously conducted sys-
tematic synthesis of theoretical literature which builds on
previous research by attempting to use quality assessment
criterion and successfully applying qualitative synthesis to
theoretical literature. By drawing together and filling gaps
in the existing theoretical literature, we have developed a
clear, comprehensive theory of change for how PYD inter-
ventions are intended to reduce substance use and vio-
lence. As mentioned in our introduction, our broader
review also included a synthesis of empirical evaluations of
current PYD interventions. Although not yet published,
this element of the review found that interventions were
not informed by the theories of change synthesised in this
paper and so provided little useful evidence about the ef-
fectiveness of the PYD approach. The very fact that previ-
ous evaluations have not focused on theoretically informed
interventions is evidence for the need for the present
paper. We recommend that our theory of change be used
in future systematic reviews to inform inclusion criteria.
We also recommend that new empirical evaluations of the
effectiveness of PYD draw on our theory of change when
developing intervention logic models [58] to ensure that
the interventions evaluated properly embody the PYD
approach. We also hope our clear exposition of the PYD
theory of change will help policy-makers and practitioners
make more informed decisions about whether PYD inter-
ventions might be appropriate to local needs.
However, gaps remain, which PYD theorists should ad-
dress, particularly regarding the pathways via which PYD
programmes brings about intentional self-regulation and
how particular assets might offer protection against par-
ticular risk behaviours. There is also a need for future the-
ory syntheses to develop more useable criteria for assessing
quality.
Additional files
Additional file 1: Search on Psycinfo (EBSCO) 7/11/2013.
(DOCX 15 kb)
Additional file 2: PRISMA checklist. (DOCX 22 kb)
Competing interests
The authors declare that they have no competing interests.
Authors’contributions
ChB designed and directed the review, contributed to all stages and drafted
the manuscript. KH contributed to screening, quality assessment and synthesis
and drafting. KD managed the review and contributed to design and drafting.
JT, AF, SM, GJMT and RC contributed to the design of the review, methods of
synthesis and drafting. CaB commented on the synthesis and contributed to
drafting. All authors read and approved the final manuscript.
Acknowledgements
This project is funded by a grant from the National Institute for Health
Research Public Health Research programme (grant PHR 12/153/19). This
report presents independent research commissioned by the National
Institute for Health Research (NIHR). The views and opinions expressed by
authors in this publication are those of the authors and do not necessarily
reflect those of the NHS, the NIHR, MRC, CCF, NETSCC, the Public Health
Research programme or the Department of Health. The work was
undertaken with the support of The Centre for the Development and
Evaluation of Complex Interventions for Public Health Improvement
(DECIPHer), a UKCRC Public Health Research Centre of Excellence. Joint
funding (MR/KO232331/1) from the British Heart Foundation, Cancer
Research UK, Economic and Social Research Council, Medical Research
Council, the Welsh Government and the Wellcome Trust, under the auspices
of the UK Clinical Research Collaboration, is gratefully acknowledged.
Author details
1
Department of Childhood, Families and Health, University College London
Institute of Education, 18 Woburn Square, WC1H 0NR London, UK.
2
Cardiff
School of Social Sciences, Cardiff University, CF10 3BD Cardiff, UK.
3
Division
of Health Sciences, Warwick Medical School, University of Warwick, CV4 7AL
Coventry, UK.
4
Forest School, 2 College Place, E17 3PY London, UK.
5
School
of Social and Community Medicine, University of Bristol, Canynge Hall, 39
Whatley Road, BS8 2PS Bristol, UK.
Received: 4 June 2015 Accepted: 3 February 2016
Bonell et al. BMC Public Health (2016) 16:135 Page 11 of 13
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