The study
Aims
The aims of this study were two-fold: to evaluate the effects
of behaviour modification on anthropometric indices and to
explore if behaviour modification could improve eating
behaviour in adolescents.
Design
A quasi-experimental design was adopted.
Participants
The participants were randomly selected and assigned to
two groups. The groups comprised 30 obese adolescents
aged from 11–15 years who participated in a 6-month
intervention program. The sample size calculation for this
study was based on previously reported intervention
changes in weight and body mass index (BMI) in children.
These suggested that at least 14 in each group would allow
detection of statistically significant differences with an
effect size of 0Æ80 (Breat et al. 2004). The participants
had BMI greater than the 95th percentile related to
standards for age and gender (Wong & Whaley 2007).
The exclusion criteria were pre-existing disease or an
organic cause for obesity and receiving any medication that
might interfere with the study. All participants were
examined by a Registered Paediatric Nurse to exclude
these factors.
Intervention
Four-hour structured sessions for the experimental group
were held weekly for 16 weeks in small groups. Each
session involved 2 hours of behaviour modification or
dietary instruction and 2 hours of yoga therapy. The first
appointment, which lasted 2 hours, was held with the
adolescents and their parents, and was aimed at familiarizing
them with the components of the program, understanding
motivation for weight loss and trying to encourage
the family to support the adolescents. The program covered
standard behavioural strategies such as self-assessments and
monitoring food (reducing total energy and fat intake,
increasing fruit and vegetable consumption and making
healthy beverage and snack choices); additional measures
taught were stimulus control, cognitive restructuring,