Table. Severity Label Definitions and Corresponding Treatment Intensity Groups Obtained From Initial Clinical Assessments^a.

Acne Severity Level	Treatment Intensity Group	Associated Severity Label by Clinicians	Final Clinical Severity Label Used in the Proposed Scale
1	No treatment necessary	Clear	Clear
2	Benzoyl peroxide wash and/or a mild topical retinoid	Almost clear	Almost clear
3	Benzoyl peroxide wash and a topical retinoid	Mild	Mild
4	Benzoyl peroxide wash and a stronger topical retinoid or a topical retinoid and consideration of an oral antibiotic	Mild to moderate	Mild to moderate
5	Benzoyl peroxide wash, topical treatment, and an oral antibiotic	Moderate	Moderate
6	Same as 5, but start considering isotretinoin	Moderate to severe	Moderate to less severe
7	Same as 5, but recommend isotretinoin	Severe	Less severe
8-9	Should be on isotretinoin (more severe = 8) (case 1) or, in very severe cases, start with a lower dosage of isotretinoin (to avoid flaring) and add corticosteroids (case 2)	More severe	Severe (case 1) or very severe (case 2)

^aAcne images were grouped into sets of lowest to highest perceived severity along with corresponding treatment intensities; severity labels were assigned to each group by clinicians in the initial experiments, and the final severity labels were definitions used in the proposed scale.