Using the theory of planned behaviour to develop an assessment of attitudes and beliefs towards prosthetic use in amputees

Purpose:?To develop a questionnaire based on the theory of planned behaviour (TPB) to predict prosthetic use.

Method:?In part one, 31 amputees over 50 years of age with peripheral arterial disease completed attitude items containing 27 bipolar adjectives and open-ended questions on behavioural, normative and control beliefs relating to using the prosthesis. Academic, clinical and patient experts (n?=?12) identified bipolar adjectives with best face validity. In part two, 15 amputees completed three behavioural format questions relating to prosthetic use and were asked to indicate the easiest to answer.

Results:?Following the completion of the attitude items by the amputees and the expert panel review, 5 items remained (Cronbach's alpha?=?0.87) with corrected item-total correlations ranging from 0.43 to 0.83. Modal behavioural beliefs concerned mobility (46.5%), independence (25.6%) and participation restrictions (16.3%), normative beliefs concerned family (33.3%), NHS staff (31.7%), friends (19.1%) and other patients (15.9%) and control beliefs concerned stairs (21.1%), slippery/rough surfaces (28.9%), disabled facilities (54.8%) and people helping (22.6%). In relation to part 2, an exact numerical report of hours and days of prosthetic use was found easiest to answer (73%).

Conclusions:?Based on this qualitative and quantitative development work, the questionnaire contains five attitude items, six behavioural, eight normative, eight control belief items and two self-report questions of the behaviour.