Acne Vulgaris Outcome Measures Have High Variability Across Published Studies

acne face woman hands fingers
Conceptual of problems on woman skin.
Investigators assessed the physician-based evaluation methods applied to 186 articles about acne published from 2000 to 2019.

Outcome measures for acne vulgaris are both diverse and heterogeneous in the highly influential dermatology journals and vary by time, region, and study design, researchers reported in the Journal of Dermatology.

Investigators analyzed the physician-based evaluation methods that were used in 186 articles about acne published from January 2000 to June 2019 in 5 dermatology journals: the Journal of the American Academy of Dermatology, JAMA Dermatology, the British Journal of Dermatology, Journal of the European Academy of Dermatology and Venereology, and Acta Dermato-Venereologica.

According to the study authors, acne articles published from 2010 to 2019 used Investigator Global Assessment (IGA; odds ratio [OR], 5.808; 95% CI, 1.894-17.811) more frequently and the Leeds technique (OR, 0.282; 95% CI, 0.098–0.812) less frequently, compared with articles published from 2000 to 2009. In controlled experimental studies, lesion counting (OR, 238.637; 95% CI, 46.795-1216.954), IGA (OR, 9.177; 95% CI, 3.053-27.586), and the Leeds Revised Acne Grading System (LRAGS; OR, 10.844; 95% CI, 3.050-38.559) were preferred, compared with preferred methods in observational studies.

In studies from North America, lesion counting (OR, 4.573; 95% CI, 1.173-17.836) and IGA (OR, 11.330; 95% CI, 3.487-36.818) were used more often and LRAGS (OR, 0.171; 95% CI, 0.039-0.758) less often, compared with European studies.

“Overall, the largest number of studies was conducted in Europe, followed by North America, and Asia,” stated the researchers. “Acne-related studies are being actively conducted regardless of region; however, most studies in this analysis were conducted in Europe, as 3 of the 5 journals are published in Europe. Of the 186 papers, 152 used global severity grading and 103 used lesion counting.”

Several study limitations were noted, as the articles were extracted from only 5 dermatology journals during the last 20 years, and the investigators did not conduct qualitative evaluation of each evaluation method.

“[T]his study demonstrated the diversity and heterogeneity of acne outcome measures even in highly influential dermatology journals,” researchers concluded. “Application of outcome measures in clinical acne studies varied by time, region, and study design. This is due to the limitations of current methods and suggests the importance of developing a core outcome measure.”


Cho SI, Yang JH, Suh DH. Analysis of trends and status of physician-based evaluation methods in acne vulgaris from 2000 to 2019. Published online November 12, 2020. J Dermatol. doi: 10.1111/1346-8138.15613