Application of a Diabetic Foot Smart APP in the measurement of diabetic foot ulcers

Aims: In the early stage, we developed an intelligent measurement APP for diabetic foot ulcers, named Diabetic Foot Smart APP. This study aimed to validate the APP in the measurement of ulcer area for diabetic foot ulcer (DFU). Methods: We selected 150 DFU images to measure the ulcer areas using three assessment tools: the Smart APP software package, the ruler method, and the gold standard Image J software, and compared the measurement results and measurement time of the three tools. The intra-rater and inter-rater reliability were described by Pearson correlation coefficient, intra-group correlation coefficient, and coefficient of variation. Results: The Image J software showed a median ulcer area of 4.02 cm(2), with a mean measurement time of 66.37 +/- 7.95 s. The ruler method showed a median ulcer area of 5.14 cm(2), with a mean measurement time of 171.47 +/- 46.43 s. The APP software showed a median ulcer area of 3.70 cm(2), with a mean measurement time of 38.25 +/- 6.81 s. There were significant differences between the ruler method and the golden standard Image J software (Z = -4.123, p < 0.05), but no significant difference between the APP software and the Image J software (Z = 1.103, p > 0.05). The APP software also showed good inter-rater reliability and intra-rater reliability, with both reaching 0.99. Conclusion: The Diabetic Foot Smart APP is a fast and reliable measurement tool with high measurement accuracy that can be easily used in clinical practice for the measurement of ulcer areas of DFU.