Introduction

Few workers in the addictions field can fail to have noticed the ‘stages of change’ model of Prochaska and DiClemente (Prochaska and DiClemente, 1986; Prochaska et al., 1992). The model appears to offer a general, comprehensive, and theoretically coherent account of how people change their behaviour. It clearly has immense intuitive appeal to teachers, practitioners and researchers in the addictions field. With one exception (Davidson, 1992), commentators have been unanimous in their praise and enthusiasm for the model. Orford (1992) likened the development of the model to a Kuhnian paradigm shift, and Stockwell (1992) compared the reaction of some of his colleagues to the recent announcement that a fifth stage of change had been identified to the awe that might accompany the discovery of a new planet.

This chapter provides a critical assessment of the stages of change model. It addresses two key assumptions of the model: (1) that change in addictive behaviour involves movement through a sequence of stages; and (2) that different processes of change are emphasised in different stages and promote progression through the sequence. The questionnaire instruments designed to assess the stages and processes of change are also examined. The chapter does not attempt to give an exhaustive review of the literature in this area. It focuses on Prochaska and DiClemente's own published papers. Related work on readiness to change (Rollnick et al., 1992; Heather et al., 1993) is not discussed, though some of the comments also apply to that approach. Nor do we compare the stages of change model with other decision-making models that have been applied to addictive behaviours such as the Theory of Reasoned Action/Planned Behaviour and the Subjective Expected Utility Model (Sutton, 1987, 1989). Most applications of the stages of change model have been to smoking. Orford (1992) has suggested that decision-making approaches may be less applicable to alcohol and drug abuse.

The stages of change

The stages of change model

The stages of change have been described in terms of a revolving door metaphor, as depicted in Figure 12.1. As an aside, it is worth noting that the metaphor is not strictly accurate since a person entering a revolving door stays in the same compartment ('stage’) until exiting.