Reliability assessment and validation of the Melasma Area and Severity Index (MASI) and a new modified MASI scoring method.
BACKGROUND
The Melasma Area and Severity Index (MASI), the most commonly used outcome measure for melasma, has not been validated.


OBJECTIVE
We sought to determine the reliability and validity of the MASI.


METHODS
After standardized training, 6 raters independently rated 21 patients with mild to severe melasma once daily over a period of 2 days to determine intrarater and interrater reliability. Validation was performed by comparing the MASI with the melasma severity scale. The darkness component of the MASI was validated by comparing it with the difference between mexameter scores for affected versus adjacent normal-appearing skin. The area component of the MASI was validated by comparing it with the area of each section of the face determined by computer-based measurement software.


RESULTS
The MASI score showed good reliability within and between raters and was found to be valid when compared with the melasma severity scale, mexameter scores, and area measurements. Homogeneity assessment by raters showed the least agreement and can be removed from the MASI score without any loss of reliability.


CONCLUSIONS
Patients were limited to Hispanic, African, and Asian backgrounds.


CONCLUSIONS
The MASI is a reliable measure of melasma severity. Area of involvement and darkness are sufficient for accurate measurement of the severity of melasma and homogeneity can be eliminated.
Pandya
Amit G
AG
Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9190, USA. amit.pandya@utsouthwestern.edu
Hynan
Linda S
LS
Bhore
Rafia
R
Riley
Fransell Copeland
FC
Guevara
Ian L
IL
Grimes
Pearl
P
Nordlund
James J
JJ
Rendon
Marta
M
Taylor
Susan
S
Gottschalk
Ronald W
RW
Agim
Nnenna G
NG
Ortonne
Jean-Paul
JP
D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000367:Age Factors; D000704:Analysis of Variance; D044466:Asian People / Q000706:statistics & numerical data; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005544:Forecasting; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008548:Melanosis / Q000175:diagnosis* / Q000208:ethnology; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012107:Research Design / Q000639:trends*; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D014481:United States; D055815:Young Adult