Beyond stages of change: Multi-determinant continuum models of action readiness and menu-based interventions

The merits of modelling action readiness as a series of stages is discussed, focusing on the Health Action Process Approach (HAPA) which postulates a motivational stage (for non-intenders) and a volitional stage (for intenders). The HAPA helpfully clarifies that the relationship between self-efficacy and action may be different for inexperienced intenders and experienced actors. This model also usefully distinguishes between different types of planning undertaken by intenders and it is suggested that further specification of planning tasks could explain why some intenders act while others do not. Despite the advantages of the HAPA, it is argued that the distinction between intenders and non-intenders is fuzzy and unstable and that demarcation of the stage boundary is arbitrary. A multi-determinant, multi-goal continuum approach is recommended. Such modelling recognises graded discontinuities throughout the development of action readiness from attitude formation to behaviour change maintenance. It is argued that menu-based interventions designed to deliver different messages and materials to people with different action-readiness deficits may be more cost effective than stage-tailored interventions.