Measuring progress to healing: A challenge and an opportunity

Area of Science:

• Wound healing research
• Clinical trial methodology
• Vascular medicine

Background:

• Complete healing is a difficult endpoint for evaluating wound healing interventions due to wound heterogeneity and lengthy study durations.
• High-quality randomized controlled trials are rare because of challenges in matching groups and achieving statistical significance and generalizability.

Purpose of the Study:

• To determine the healing trajectory of venous leg ulcers treated with multi-component compression bandaging.
• To identify reliable surrogate endpoints for wound healing that allow for more efficient study designs.

Main Methods:

• Analysis of healing in venous leg ulcers over a 4-week period.
• Measurement of gross area healed, percentage area healed, and wound margin advance.
• Assessment of the linearity of these healing metrics.

Main Results:

• Venous leg ulcer healing follows a linear trajectory over 4 weeks when treated with multi-component compression bandaging.
• Wound margin advance was the most linear and reliable surrogate metric, independent of initial ulcer size.
• Linear healing trajectories facilitate the identification of accelerated healing from interventions.

Conclusions:

• The linear nature of wound healing, particularly wound margin advance, supports the use of self-controlled or crossover trial designs.
• These designs offer advantages in statistical power and speed for evaluating interventions for venous leg ulcers.
• Wound margin advance is a robust and size-independent surrogate for assessing healing in venous leg ulcers.