Critical appraisal of the model (TTM) Flashcards
Outline the criticisms of the TTM by Weinstein et al. and Sutton.
1) It is difficult to determine whether behaviour change occurs in specific stages or along a continuum. The absence of qualitative differences between stages may be due to either the absence of stages itself or the stages have been incorrectly assessed and identified.
2) Changes between stages may happen so quickly as to make them unimportant/redundant.
3) Interventions based on the stages of change model may only work because the individual believes they are receiving specialised help and advice, rather than due to the effectiveness of the model itself.
What are additional criticisms of the model?
- Godin et al. - little empirical evidence to suggest that the contemplation stage differs from the preparation and planning stage. Past behaviour has been subsequently found to be a powerful predictor of future behaviour change efforts, too much emphasis is placed on the model in predicting behaviour change.
- Budd and Rollnick - people may not fit easily into the five discrete stages – the stages may be continuous rather than discrete.
- Marks et al - the model does not address the social aspects of health behaviours and how this can help or hinder an individual’s efforts in changing their behaviours.
- further additional criticism - cannot be easily applied to children!
Outline the criticisms by West (2005).
1) The boundaries between the stages are arbitrary and not based on any empirical evidence, i.e. an individual is in the preparation stage who is planning to stop smoking within the next 30 days (provided that the smoker has attempted to quit for at least 24 hours in the past 12 months) - why these particular numbers?
2) Classifying individuals into different stages assumes that individuals typically make coherent and stable plans - does not account for how some people can completely change behaviour with apparent suddenness, even in response to small triggers. (Larabie study - more than half of reported quit attempts involved no planning or preparation at all).
3) Individuals struggle to change behaviour due to fact that unhealthy habit patterns become entrenched and semi‐automated through repeated reward and punishment - operates outside conscious awareness, doesn’t follow decision‐making rules such as weighing up costs and benefits.
4) There appears to be no convincing evidence that moving an individual closer to action actually results in a sustained change in behaviour at a later date.
5) The problems with the model are so serious that it has held back advances in the field of health promotion.
6) The model is used as an excuse to provide little rigorous interventions to individuals in the pre-contemplation stage when evidence suggests that smoking cessation information and advice should be offered rather than trying to convince the person to change their behaviour.
7) The model does not take into account the neurobiological characteristics of addiction and dependency, assumes that addicts behave rationally when that is not always the case.
What does West propose should replace the TTM?
1) Advocates for a new theory/model which incorporates decision‐making and motivational processes that are not necessarily accessible to conscious awareness, and which takes into account the fact that the behaviours reflect the moment‐to‐moment balance of motives which arise under specific circumstances. These should be described/explained and how they shape/change an individual’s desires and values. 2) States that in the absence of a new theory, should revert back to the common sense model, as this was more rational - individuals were asked simply about their desire/ability to change and it was recognised that this was affected by a range of personal and situational factors including addiction.
What are Herzog’s (2005) criticisms?
- Herzog backs up West’s criticisms:
1) The model lacks scientific merit - care should have been taken to formulate how stages of change were conceptualised and measured, but there has never been a peer‐reviewed account of the developmental research that led to the creation of the stages of change algorithm, and it is unclear if any systematic developmental research took place at all.
2) Characterises the TTM as a “marketing gimmick” - the model became popular very quickly despite lack of scientific evidence, and believes the TTM has cornered the market so research on addiction treatment was dominated by the TTM and other more promising (and more scientific!) methods were not looked into.
What were DiClemente’s replies to West’s criticisms?
1) West’s critique is a criticism of the stages of change and not the entire model - the dimensions of the TTM offer a framework that makes explicit that elements of human intentional behaviour are process and not just stages.
2) The stages themselves have always been considered states and not traits, and West is fundamentally misinterpreting them.
3) Readiness to change is not a single construct but a compilation of tasks and accomplishments that can produce either momentary change or sustained change, or both. West places too much emphasis on sustained change being the main goal of the TTM.
