Personalised Assistive Devices Approach for Diabetic Foot Ulcer Prevention (DIASSIST)

Cost-utility of an Integrated Personalised Assistive Devices Approach to Reduce Foot Ulcer Recurrence in Diabetes (DIASSIST): a Multicentre Randomised Controlled Trial

Preventing foot ulcers in people with diabetes can reduce costs and increase quality of life. Despite availability of various interventions to prevent foot ulcers, recurrence rates remain high. We hypothesise that a multimodal approach incorporating a variety of orthotic interventions that matches an individual person's need can reduce ulcer recurrence with beneficial cost-effectiveness and cost-utility.

Study Overview

• Status: Completed
• Conditions: Diabetic Foot Ulcer
• Intervention / Treatment: Device: Custom-made shoes: pressure-optimized; Device: Custom-made indoor shoes: pressure optimized; Device: Foot temperature monitoring; Behavioral: Education

• Study Type: Interventional
• Enrollment (Actual): 126
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Amsterdam, Netherlands
    • Amsterdam UMC
  • Beverwijk, Netherlands
    • Rode Kruis Ziekenhuis
  • Delft, Netherlands
    • Reinier de Graaf Gasthuis
  • Hoofddorp, Netherlands
    • Spaarne Gasthuis
  • Veldhoven, Netherlands
    • Maxima Medisch Centrum

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Diabetes mellitus type 1 or 2
• Age 18 years or above
• Loss of protective sensation based on the presence of peripheral neuropathy
• A healed plantar foot ulcer or foot amputation in the preceding 4 years until two weeks before study inclusion
• In possession of custom-made orthopaedic shoes, defined as "Orthopaedic shoes type A" or "Orthopaedic shoes type B" , or Orthopaedic Provision in Regular Footwear (OVAC), according to the Dutch healthcare system
• Ability to provide informed consent

Exclusion Criteria:

• Foot ulcer or open amputation site(s)
• Active Charcot's neuroarthropathy
• Foot infection, based on criteria of the PEDIS classification
• Amputation proximal to the metatarsal bones in both feet
• Healed ulcer on the apex of digitus 2-5 as the only ulcer location in the past 4 years, as surgical intervention (flexor tenotomy) is a more likely and guideline-recommended treatment for such patients, rather than the multimodal care under investigation
• Severe illness that would make 12-months survival unlikely, based on the clinical judgment by the physician
• Concomitant severe physical or mental conditions that limit the ability to follow instructions for the study, based on clinical judgment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Multimodal care; Multimodal personalised treatment	Device: Custom-made shoes: pressure-optimized; Pressure-optimized custom-made shoes: evaluated and optimized using in-shoe pressure analysis, and re-evaluated after 6 months.; Device: Custom-made indoor shoes: pressure optimized; Pressure-optimized custom-made indoor shoes: evaluated and optimized using in-shoe pressure analysis, and re-evaluated after 6 months. Specifically designed for indoor use.; Device: Foot temperature monitoring; Personalised at-home daily foot temperature monitoring at high-risk regions.; Behavioral: Education; Personalised patient education consisting of quantitative feedback on in-shoe pressures, temperature measurements and footwear use and, in addition, motivational interviewing where indicated and needed to improve device use.
No Intervention: Usual care; Usual care as offered to high-risk patients as offered in the Netherlands

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cost-utility (as the primary economic outcome)	defined as the ratio between costs related to foot care and quality-adjusted life years, based on the health utilities associated with the scoring profiles on the EQ-5D-5L with Dutch reference scores	12 months (full study period)
Adherence to wearing custom-made footwear (as the primary patient-related outcome)	defined as the percentage of steps taken in prescribed footwear, calculated by combining physical activity and wearing time measurements	12 months (full study period)
Foot ulcer recurrence during the 12-months follow-up (as the primary clinical outcome)	defined as "a break of the skin of the foot that involves as a minimum the epidermis and part of the dermis, in a person who has a history of foot ulceration, irrespective of location and time since the previous foot ulcer", with the first ulcer in the study period recorded as primary outcome and percentage participants with ulcer recurrence on group level as primary outcome	12 months (full study period)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cost-effectiveness	defined as the ratio between costs related to foot care and foot ulcer recurrence on any location of the foot	12 months (full study period)
Plantar foot ulcer recurrence	following the definition of foot ulcer recurrence (outcome 3), but then limited to the plantar side of the foot	12 months (full study period)
Foot ulcer recurrence at three predefined high-risk locations	following the definition of foot ulcer recurrence (outcome 3), but then limited to a maximum 3 high risk locations per participant, specified at the start of the study, based on barefoot pressures, ulcer history, pre-ulcerative lesions or signs of abundant callus	12 months (full study period)
Costs related to foot care (from a societal and medical perspective)	Costs will be calculated for each participant as the product sum of resource volume data and their respective unit costs. Resource volume data will be obtained from the completed study specific versions of the institute for Medical Technology Assessment (iMTA) Medical Consumption Questionnaire (iMCQ) and iMTA Productivity Cost Questionnaire (iPCQ), as these contain the volume data on healthcare resource utilization, out-of-pocket expenses and loss of productivity related to foot care. Foot care includes both care for ulcer prevention (e.g. podiatry appointments, rehabilitation physician consultations) and for ulcer treatment (e.g. multidisciplinary treatment, hospitalization, surgery). Reference prices for unit costs will be based on the most recent Dutch manual for costing in healthcare research available at the time of analysis. All costs will be summed during the entire study period.	12 months (full study period)
Quality-adjusted life years	based on the health utilities associated with the scoring profiles on the EQ-5D-5L with Dutch reference scores. This will be monitored during the entire study period.	12 months (full study period)

Collaborators and Investigators

• Sponsor: Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)
• Collaborators: ZonMw: The Netherlands Organisation for Health Research and Development
• Investigators: Principal Investigator: Sicco Bus, Prof, Amsterdam UMC

Publications and helpful links

General Publications

• Vossen LE, van Netten JJ, Bakker CD, Berendsen HA, Busch-Westbroek TE, Peters EJG, Sabelis LWE, Dijkgraaf MGW, Bus SA. An integrated personalized assistive devices approach to reduce the risk of foot ulcer recurrence in diabetes (DIASSIST): study protocol for a multicenter randomized controlled trial. Trials. 2023 Oct 12;24(1):663. doi: 10.1186/s13063-023-07635-z.

Study record dates

Study Major Dates

• Study Start (Actual): March 2, 2022
• Primary Completion (Actual): October 2, 2025
• Study Completion (Actual): March 30, 2026

Study Registration Dates

• First Submitted: January 17, 2022
• First Submitted That Met QC Criteria: February 10, 2022
• First Posted (Actual): February 11, 2022

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: diabetes; prevention; foot ulcer; cost-utility
• Additional Relevant MeSH Terms: Endocrine System Diseases; Vascular Diseases; Cardiovascular Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetic Angiopathies; Diabetes Complications; Skin Diseases; Skin Ulcer; Leg Ulcer; Diabetic Neuropathies; Foot Diseases; Nutritional and Metabolic Diseases; Skin and Connective Tissue Diseases; Diabetes Mellitus; Diabetic Foot; Foot Ulcer; Socioeconomic Factors; Population Characteristics; Educational Status
• Other Study ID Numbers: NL78943.018.21

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

IPD Plan Description

Data can be made available after an embargo period, to allow the research team to write all prespecified publications. The embargo period is required, as publications may often follow once the project has already ended. The embargo period will be a maximum 2 years, to allow the research sufficient time to finish the publications as specified in the protocol. If publications are available earlier, the embargo will end earlier.

Conditions for reuse will apply, but have yet to be finalized.

• IPD Sharing Time Frame: 2 years after study completion and for 15 years
• IPD Sharing Access Criteria: to be determined
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No