Purpose: Numerous tools are available to assess acne severity. It is important to have an acceptable and easy to use tool for acne assessment for many reasons, such as initial assessment and follow-ups, clinical trials, and comparisons of clinical studies. The aim was to investigate the agreement between different observers (inter-observer variation) in the evaluation using the Global Acne Grading System (GAGS) and Investigator Global Assessment of Acne (IGA). Besides, to investigate the correlation between the assessment scores and its relation to the quality of life scales Dermatology Life Quality Index (DLQI) and the Cardiff Acne Disability Index (CADI).Patients and Methods: This was a prospective study. Four investigators involved to evaluate the study subject surveyed 54 patients complaining of acne using IGA and GAGS scores (DLQI and CADI).Results: A significant relation was seen between GAGS and IGA (Pearson chi-square test p= 0.001), and they demonstrated excellent inter-rater reliability. There was no correlation between IGA and quality of life measures (CADI nor DLQI). However, there was a significant weak correlation between GAGS and CADI.Conclusion: The two methods for acne severity assessment are reliable, and they are correlated. Quality of life concerning acne is not correlated with the severity of the disease.

Keywords: acne, severity, assessment