Understanding adherence to ankle-foot orthoses, an application of the theory of planned behaviour

Student thesis: Doctoral Thesis


Ankle-foot orthoses (AFOs) are used to manage mobility disability in a wide range of conditions such as stroke, multiple sclerosis, arthritis, and trauma. However, sub-optimal adherence has been identified as a major concern. Poor adherence to AFOs may result in diminished physical and mental health outcomes, and is also an inefficient use of scarce resource. In addition, little is known about the extent of use of AFOs in the longer term. Therefore, this thesis set out to initially understand the prevalence of adherence to AFOs, and the relationship between adherence to AFOs and health and functioning outcomes.;The International Classification of Functioning Disability and Health (ICF, WHO, 2001) was used as a framework to define health outcomes. The first investigation was a cross-sectional survey, conducted with 157 participants from NHS Greater Glasgow and Clyde, who had been prescribed an AFO for a range of conditions. The adherence rate to use of AFOs as recommended was 56%. This study demonstrated that AFO use as recommended was associated with better physical and mental health outcomes.;Therefore, an understanding of potentially modifiable factors, which can improve adherence to AFOs, offers an alternative method of optimising outcomes of AFO use.;The Medical Research Council's framework for complex interventions (Craig et al., 2013) identifies the need for theory-driven research to inform interventions. Consequently, this thesis used a theoretical approach to attempt to understand adherence to orthoses. Firstly, the Theory of Planned Behaviour (TPB, Ajzen, 1991) was identified as a potentially appropriate model. Then, a meta-analysis was conducted, which drew on the wider health adherence literature, to review the efficacy of the TPB in understanding health adherence behaviours in conditions, which may give rise to an orthotic intervention.;This found that the TPB accounted for 28.3% of the variance in intentions and 14% of the variance in adherence behaviours. Attitudes and Perceived Behavioural Control (PBC) were significant predictors of intention, and intention was a significant predictor of behaviour. In line with the TPB, intention mediated the effects of attitude and PBC on behaviour. This suggested the TPB might offer a useful model to investigate adherence to AFOs.;This thesis then applied the TPB to modelling AFO use in people with stroke. Stroke was selected as the focus of this investigation, as it is the leading cause of acquired adult disability worldwide (McGrath, Canavan, & O'Donnell, 2018), and, in the first study, was identified as the most common condition for which an AFO is prescribed. In addition, Scotland has a high incidence of stroke, compared to other UK nations, and improving the treatment and care of stroke is a clinical priority (Scottish Government, 2014a).;In order to conduct a TPB investigation, firstly, a beliefs elicitation study was conducted with 13 participants who had been prescribed an AFO by NHS Lanarkshire following stroke. This study enabled elicitation of attitudinal, normative and control beliefs, in line with the TPB model.;Participants reported more advantages compared to disadvantages of using AFOs, suggesting that they had a generally positive attitude towards AFO use. The most commonly stated advantages were 'increased mobility' and 'supports the position of the leg or foot'. The most common disadvantage detailed was 'discomfort', followed by 'problems with footwear size' and 'problems with footwear style'. Participants also identified a far greater number of people who would approve of AFO use, compared to people who would disapprove of AFO use suggesting that support for use of AFOs from a wide range of normative groups is high.;Family and health professionals were the most frequently elicited supporti
Date of Award26 Sep 2019
Original languageEnglish
Awarding Institution
  • University Of Strathclyde
SupervisorSusan Rasmussen (Supervisor) & Mark Elliott (Supervisor)

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