The Scarbase Duo(®): Intra-rater and inter-rater reliability and validity of a compact dual scar assessment tool.

•The Scarbase Duo® measures two scar properties: trans-epidermal water loss and colorimetry.•Intra- and inter-rater reliability was good-to-excellent for TEWL and colorimetry on scars.•The Scarbase Duo® was validated against other established tools of TEWL and colorimetry assessment.•The Scarbase Duo® was easy to use and compact, but required link-up to a laptop computer.•The Scarbase Duo® is a reliable scar assessment tool however clinical use requires standardised conditions.