The reproducibility and clinical utility of the 3D camera for measuring scar height, with a protocol for administration.

BACKGROUND: This study aimed to determine the reproducibility and clinical utility of a 3D camera for measuring burn scar height in adults.

METHODS: Participants from a larger prospective longitudinal study were included. Reproducibility data were collected using an immediate test-retest interval and a 1-2 week test-retest interval and included reliability and agreement. The LifeViz™ 3D camera was used to measure scar height. Reproducibility was tested using the Intraclass Correlation Coefficient (ICC), percentage agreement within 1 mm between test and retest, standard error of measurement, smallest detectable change (SDC) and Bland Altman limits of agreement.

RESULTS: Burn scar images from 55 adult participants were included. Intra-rater reliability was acceptable using an immediate retest interval (maximum and minimum height ICC=0.85, 0.86 respectively). Agreement using an immediate retest interval was borderline acceptable (maximum and minimum height SDC=1.11, 0.69 respectively) to detect changes of close to 1 mm. Reproducibility was largely not acceptable using a 1-2 week test-retest interval (eg, maximum and minimum height ICC=0.34, 0.68 respectively; maximum and minimum height SDC=2.66, 1.16). The clinical utility of the camera was supported for scars over relatively flat areas and well-defined border margins. A protocol for administration of the camera was developed.

CONCLUSION: The 3D camera appears capable of detecting gross changes or differences in scar height above the normal skin surface, in adults with scars over relatively flat areas and well-defined border margins. However, further testing of reproducibility using a shorter test-retest interval than 1-2 week retest is recommended to confirm the suitability of the device for measuring changes or differences in scar height.