Economic Evaluation of Lower Limb Prostheses for Persons With a Knee-disarticulation or Transfemoral Amputation

Primary outcomes

1. Costs related to lower limb prosthesis use

   Time frame: At the baseline, participants were asked to fill out the questionnaire over a retrospective period of six months

   To get insight in the costs, two existing questionnaires were combined: the Productivity Cost Questionnaire (iPCQ) and the Medical Consumption Questionnaire (iMCQ).

   The iMCQ is used to measure medical consumption. It includes questions related to the number of appointments with health care providers. The iPCQ measures and values productivity losses. It looks at absenteeism, presenteeism, productivity losses and unpaid work. As this study focussed on costs related to lower limb prostheses, questions about appointments with a dietician and speech therapist, and trips to the emergency room were replaced with questions about the type of prosthesis and the number of appointments with their prosthetist. Finally, questions about personal costs related to the acquisition and repairs of the prosthesis, as well as personal expenses were added. As this questionnaire looks at number of appointments and costs, there is no minimum or maximum value score.

2. Health-related quality of life (HRQOL) 1

   Time frame: At the baseline, participants were asked to fill out the questionnaire based on their health status that day.

   To evaluate the HRQOL, participants were asked to fill out the Dutch version of the EuroQol - five dimensions - five levels (EQ-5D-5L). This is a self-assessment tool that consists of five questions about mobility, self-care, daily activities, pain and anxiety/depression. For each question, the participant can answer with five response levels: no problems, slight problems, moderate problems, severe problems, extreme problems/unable to do so. The Dutch scoring algorithm for the EQ-5D-5L was used to compute a solitary value representing the health status of the participant. The calculated values fall within the range of -0.446 to 1, where higher scores denote enhanced HRQOL.

3. Health-related quality of life (HRQOL) 2

   Time frame: At the baseline, participants were asked to fill out the questionnaire based on their health status that day.

   At the end of the EQ-5D-5L, participants were asked to rate their perceived health that day on a visual analogue scale (VAS) of 0 (worst health imaginable) to 100 (best health imaginable).

4. Prosthesis-related quality of life

   Time frame: At the baseline, participants were asked to fill out the questionnaire over a retrospective period of four weeks.

   To measure the prosthesis related quality of life, participants filled out parts of the Prosthesis Evaluation Questionnaire (PEQ). The PEQ is a self-report questionnaire to evaluate prosthesis and prosthesis-related quality of life. Questions focus on use, satisfaction, quality of life, tripping and falling. The subscales used in the PEQ are not dependent on each other and can therefore be used independently to fit the research question. For this study, three subscales were utilized: utility, ambulation and well-being.

   The questions are scored on a visual analogue scale (VAS) from 0-100. A higher score on this questionnaire is linked to a more positive outcome.