Interventions to change health-related behaviours typically have modest effects and may be
more effective if grounded in appropriate theory. Most theories applied to public health …

The transtheoretical model posits that health behavior change involves progress through six
stages of change: precontemplation, contemplation, preparation, action, maintenance, and …

This text provides the most comprehensive treatment of the design and analytic issues
involved in group-randomized trials. GRTs are comparative studies conducted to evaluate …

Background Helping young people to avoid starting smoking is a widely endorsed public
health goal, and schools provide a route to communicate with nearly all young people …

Background Suboptimal treatment adherence remains a barrier to the control of many
infectious diseases, including tuberculosis and HIV/AIDS, which contribute significantly to …

Most randomised trials allocate individual participants to different treatments. However,
cluster randomised trials in which groups of subjects are allocated to different treatments are …

The book focuses on the design of rigorous trials rather than their statistical underpinnings,
with chapters on: pragmatic designs; placebo designs; preference approaches; unequal …

The stages of change proposed by Prochaska and DiClemente have been applied to
change efforts within and outside of formal treatment and in relation to virtually any problem …

The Transtheoretical Model (TTM) has gained widespread popularity and acceptance, yet
little is known about its effectiveness as a basis for health behavior intervention. A systematic …

Motivational interviewing (MI), initially developed for addiction counseling, has increasingly
been applied in public health, medical, and health promotion settings. This article provides …