The independent Cochrane Library have just published a report questioning the effectiveness of the Stages of Change (SOC) approach to the Trans Theoretical Model (TTM) of behaviour change.
The report, available on the Cochrane Library website found that:
TTM SOC and a combination of physical activity, diet and other interventions resulted in minimal weight loss, and there was no conclusive evidence for sustainable weight loss. The impact of TTM SOC as theoretical framework in weight loss management may depend on how it is used as a framework for intervention and in combination with other strategies like diet and physical activities.
The full report can be downloaded here.