London for It enters homes through cracks in foundations, and although little heard of, it is the second leading cause of lung cancer after smoking Weinstein and Sandman Perceived susceptibility or vulnerability was found to be crucial in the transition between stage trying to decide and stage deciding to act. However, a stage-matched intervention, as with those based on the TTM, was not as successful in moving decided to act’ stage participants into action buying a home radon-testing kit, as it was in shifting the undecided participants into making a decision to act but not action necessarily. More research using stage models are needed to more clearly identify the processes that occur within and between stages in order to provide greater Figure The health action process approach model. Source Schwarzer http //userpage.fu-berlin.de/~health/hapa.htm justification for stage-matched interventions, which to date have had limited effectiveness and are more costly than one size fits all’ interventions see Chapters and for examples. London 2016.