A modified Vancouver Scar Scale linked with TBSA (mVSS-TBSA): Inter-rater reliability of an innovative burn scar assessment method

Abstract

BackgroundCurrent scar assessment methods do not capture variation in scar outcome across the burn scar surface area. A new method (mVSS-TBSA) using a modified Vancouver Scar Scale (mVSS) linked with %TBSA was devised and inter-rater reliability was assessed. MethodThree raters performed scar assessments on thirty patients with burn scars using the mVSS-TBSA. Scoring on pigmentation, vascularity, pliability and height was undertaken for the ‘best’ and ‘worst’ areas of each scar. Raters allocated the total body surface area of the scar (%TBSA) to three mVSS categories (<5, 5–10, >10). Intra-class correlation coefficient (ICC) and weighted kappa statistic (kw) were used to assess inter-rater reliability. The data were also analysed for clinically relevant misclassifications between pairs of raters. ResultsTotal mVSS scores showed ‘fair to good’ agreement (ICC 0.65–0.73) in the ‘best’ area of the scar while there was ‘excellent’ agreement in the ‘worst’ scar area (ICC 0.85–0.88). The kw of the individual mVSS components ranged from 0.44 to 0.84 and 0.02 to 0.86 for ‘best’ and ‘worst’ scar areas, respectively. Determination of scar %TBSA had ‘excellent’ reliability (ICC 0.91–0.96). Allocation of scar %TBSA to severity category <5 mVSS demonstrated ‘good to excellent’ reliability (ICC 0.63–0.80) and ‘fair to good’ reliability (ICC 0.42–0.74) for 5–10 mVSS category. However, misclassifications were observed for the total mVSS score in the ‘worst’ scar area and the allocation of scar %TBSA in the <5 mVSS category. ConclusionInter-rater reliability of mVSS scores depends on the severity of the scar area being assessed. The mVSS-TBSA method of allocation of scar %TBSA to two broad mVSS categories, namely <5 and ≥5 mVSS, has ‘good to excellent’ reliability. The mVSS-TBSA has demonstrated utility for both clinical and research purposes; however, there is potential to misclassify scar outcome in some cases.