There currently more than 1 million disabled people in the world (around 15% of the population). Different types of disability include: absence/loss of limb or sensory function, progressive neurological conditions, chronic diseases, inability or limited ability of cognitive functioning, and psychiatric disorders.
Disability can lead to a variety of negative consequences: financial, physical and mental as well as leading to higher mortality rates and unequal access to healthcare. In terms of financial consequences, 44% disabled people are likely to be employed compared to 75% in general population. Physical consequences might include the effects of immobility such as osteoporosis, pressure ulcers, venous thromboembolism, and heterotopic ossification. Mental consequences examples include depression, suicide ideation and anxiety.
Concerning mortality, people with disabilities had shorter life expectancy (by 10 years) than the general population. In terms of access to healthcare, it has been shown that disabled people have poorer health outcomes, are unable to get healthcare when they need it and feel that healthcare workers are not competent.
In order to support disabled individuals and improve their lives and health, a variety of health promotion interventions have been created for this population. It is widely agreed in health psychology research, that interventions that are evidence-based and theory-driven lead to the best results. Many theories that have been used within the interventions or to explain the mechanism behind interventions effects. The most popular theories currently are the behaviour change theory, and self-determination theory.
So which theory is the most effective in providing the basis for interventions to support disabled people?
Behaviour change theory attempts to overcome variations in the outcomes of complex behavioural support interventions by gaining an understanding of which intervention components contribute to the effectiveness of the intervention. Thus, it attempts to break down interventions into such components, called behaviour change techniques. A behaviour change technique is a ‘concrete description’ of the methods used by practitioners to change behaviour, precisely defined to allow for future replication. This approach has been used successfully in a variety of health interventions. For instance, it has been applied in interventions for older adults, in developing countries, obese and overweight adults, as well as in health interventions with mobile applications.
This suggests that this theory can be used to build an understanding of interventions for disability. However, it has been shown in a review that it is difficult to make conclusions as to whether specific behaviour change techniques are indeed effective in interventions and whether the methods for behaviour change technique identification are always accurate. Additionally, not all intervention studies include enough description to ascertain the behaviour change techniques used. Thus, this may not be the optimal method in every case.
Self-determination theory suggests people have several innate motivational resources each of which interact with the social context to stimulate optimal functioning. The motivation resources (known as basic psychological needs) are relatedness, competency and autonomy.
If those needs are satisfied, autonomous type of motivation occurs, however if they are frustrated, controlled motivation/amotivation are likely to occur. Controlled motivation is of a lower quality than autonomous and is likely to lead to less outcomes or less sustained outcomes over time. In order for the needs to be satisfied, optimal conditions should take place in the environment, known as autonomy supportive.
If the environment is controlling, then the needs are likely to becoming frustrated. Self-determination theory has been widely applied to health contexts, such as smoking cessation, weight loss, cervical cancer smears, dental hygiene, alcohol reduction, medical adherence, diabetes as well as many others. This theory has been shown to be relevant to health contexts in a review of 184 studies.
It could be that self-determination theory is more effective that behavior change theory because it has a holistic view of the person, including not only the active components of interventions but also ascertaining the level of which psychological needs are satisfied, the environment needed to satisfy the needs and the resulting motivation which leads to behaviour change.
On the whole, it seems that self-determination theory is wider and more comprehensive than behaviour change theory. On the other hand, it has been criticised as not including developmental aspects and also due to its assumption that people have innate needs.
While self-determination theory is the more convincing as a theory used to support and explain interventions for disability, it has some limitations. It remains unclear as to whether behavior change theory or self-determination theory are fully appropriate for supporting interventions for disabled people.
Image credit: Freepik
Dr Elizabeth Kaplunov is a chartered psychologist who evaluates projects about health technology for disabled and vulnerable people.