COSMIN database

A Comprehensive Critique and Review of Published Measures of Acne Severity

Agnew, T., Furber, G., Leach, M., and Segal, L.
OBJECTIVE: Acne vulgaris is a dynamic, complex condition that is notoriously difficult to evaluate. The authors set out to critically evaluate currently available measures of acne severity, particularly in terms of suitability for use in clinical trials.

DESIGN: A systematic review was conducted to identify methods used to measure acne severity, using MEDLINE, CINAHL, Scopus, and Wiley Online. Each method was critically reviewed and given a score out of 13 based on eight quality criteria under two broad groupings of psychometric testing and suitability for research and evaluation.

RESULTS: Twenty-four methods for assessing acne severity were identified. Four scales received a quality score of zero, and 11 scored 0.75), and four reported strong intra-rater reliability (ICC>0.75). The poor overall performance of most scales, largely characterized by the absence of reliability testing or evidence for independent assessment and validation indicates that generally, their application in clinical trials is not supported.

CONCLUSION: This review and appraisal of instruments for measuring acne severity supports previously identified concerns regarding the quality of published measures. It highlights the need for a valid and reliable acne severity scale, especially for use in research and evaluation. The ideal scale would demonstrate adequate validation and reliability and be easily implemented for third-party analysis. The development of such a scale is critical to interpreting results of trials and facilitating the pooling of results for systematic reviews and meta-analyses.
J Clin Aesthet Dermatol
1941-2789 (Print)
Publication year:
Biological and physiological variables:
Biological and physiological variables
Symptom status:
Physical state
Adults (18-65)
Children (0-18)
Diseases of and symptoms related to the skin and subcutaneous tissue
PRO / non-PRO:
Non-patient Reported Outcome
Type of measurement instrument:
6 - Clinical rating scales
7 - Observations
4-point photographic scale
5cm ring placed on the most severely affected area; papules, pustules and comedones within the ring are counted
9-point grading supported by text description
9-point scale supported by text description and photograph
A modified version of scale presented by Allen and Smith
Assessment made by defining the type of lesion and multiplying the number of those lesions by the severity index factor
Burton Scale
CASS - Comprehensive Acne Severity Scale
Counting of inflammatory and noninflammatory lesions. Assessment in situ
EGAE - Escala de Gravedada del Acné Española
Five zone counting according type and number of lesions.
GAGS - Global acne grading system
GEA scale - Global Acne Severity Scale
IGA - Investigators Global Assessment Scale
Leeds Global Assessment by remote assessment
Level of severity light (≤10), moderate (11–30), and severe (31+ lesions)
LRAG - Leeds Revised Acne Grading Scale
Multimodal facial imaging system
PGA - Physician Global Assessment
Photographic Standard 8-point scale
Recording type and number of lesions and categorized according to whether they are comedonal or papulopustular
Simple 3-grade acne classification
Simple mild, moderate, or severe scale for inflammatory lesions