Active but not consistent: dietary behaviour and the stages of change model

Abstract

In Stages of Change studies on dietary fat, standard algorithms allocate many respondents to the maintenance stage and their stage allocations are not always supported by objective criteria. In defining the preparation stage standard instruments emphasise inactivity allied to confident intention to change. In contrast Lamb and Joshi's (1996) staging instrument emphasises inconsistent effort, and thereby allocates inconsistently active respondents to preparation when a standard instrument might place them in action or maintenance. In the current cross-sectional study 375 respondents completed a standard algorithm, the Lamb and Joshi instrument and a 24-hour recall food diary. They also gave judgements of their current weight and diet. Unlike the standard instrument, the Lamb and Joshi instrument: (a) allocated fewer respondents to action/maintenance, (b) discriminated key behavioural stages by percent fat in diet, and (c) captured non-linear discontinuities in the respondents’ weight and diet self-perceptions. Such discontinuities in the psychosocial processes are predicted by the transtheoretical model, and support the claim that its stages are categorically distinct rather than artificially isolated points on a continuum. Distinguishing between respondents who describe themselves as consistently active and those who describe themselves as inconsistently active may help to overcome some apparent problems in the application of the transtheoretical model to behavioural change.