162 • ii: MindFulnESS in EduCATing FOR SElF-REgulATiOn And EngAgEMEnT
Reviews and Meta-Analyses
In 2014, Zenner et al. systematically reviewed the evidence regarding the effects of school-
based mindfulness interventions on psychological outcomes, using a comprehensive search
strategy designed to locate both published and unpublished studies. The team performed
systematic searches in 12 databases and further studies were identified via hand search
and contact with experts. In order to reduce bias, two reviewers independently extracted
the data, also selecting information about intervention programs, feasibility, and acceptance
(Zenner et al., 2014). The team identified 24 studies of which 13 were published. Fourteen of
the studies were conducted in North America, seven in Europe, one in Australia, and two
in Asia. Overall, of the 24 studies, 19 studies used a controlled design. When taken together,
1,348 students were instructed in mindfulness and 876 students served as controls (Zenner
et al., 2014). The students in the studies ranged from grades 1 to 12 reflecting ages 6 to 19.
The sample sizes of the studies varied substantially from 12 to 216. Eight of the studies were
implemented in elementary school (grades 1–5), two in middle school (grades 6–8), and four
studies in high school (grades 9–12).
Zenner et al. (2014) found the descriptions of the schools, neighborhoods, or participants
not very detailed. For those who did offer descriptions, the researchers reported that there
was a wide variety of school types including public schools in both urban and suburban set-
tings. The groups of studies also included a private residential school, a Catholic school for
girls, a for-fee boy’s school, a rural high school, and a public alternative high school (Zenner
et al., 2014). Of the characteristics reported, described samples were from low performing and
at-risk schools. The authors noted that it was possible that studies that did not report socio-
economic status could have included students from higher socioeconomic backgrounds. As
you know, the lack of these data makes it difficult to generalize from the findings.
The reported theoretical frameworks for studies’ programs were mindfulness (N = 24),
positive psychology (including social emotional learning [SEL]; N = 9), and executive
functioning (N = 6; Zenner et al., 2014). Many of the mindfulness-oriented programs
cited previously existing programs such as Mindfulness-Based Stress Reduction (MBSR),
Mindfulness-Based Cognitive Therapy (MBCT), Dialectic Behavior Therapy (DBT), and
Acceptance and Commitment Therapy (ACT; Zenner et al., 2014). Only two of the programs
reported using manuals that existed for more than 5 years. Thirteen of the programs used a
manual that was less than 5 years old. Nine of the programs were run ad hoc with no manual
(Zenner et al., 2014). Two thirds of the studies used manualized programs such as Mindful
Schools and Learning to BREATHE (L2B); both programs are detailed in the next section of
this chapter. According to Zenner et al., (2014), the programs defined similar objectives
related to the assessment methods and reflected the targeted areas: cognitive performance
(e.g., attention tests, creativity tests, mind wandering paradigm, grades), emotional prob-
lems (e.g., maladaptive emotion, cognition, behavior, clinical symptoms such as anxiety,
depression, test anxiety, somatic reactions, ruminative thinking styles, emotion regulation
difficulties), stress and coping (e.g., perceived stress, coping, cortisol samples with stress
test), resilience (e.g., well-being, positive and constructive emotions or affect, resiliency,
social skills and positive relationships, self-concept, self-esteem), and third-person rating
(i.e., aggressive or oppositional behavior, social skills, emotional competence, well-being,
attention, self-regulation).
Seven of the programs were taught by the teacher, 15 by an outside trainer, and two by
a teacher and outside trainer (Zenner et al., 2014). The programs varied in length from