GAGS is clinical tool for assessing the severity of acne vulgaris that was first proposed by Doshi et al in 1997.
Instructions:
Acne lesions can be divided into the following in terms of increasing severity:
- Comedones – blackheads and whiteheads
- Papules are inflamed bumps less than 1 cm in size
- Pustules are papules with a head of pus (pusheads)
- Nodules/cysts are bumps that are 1 cm or larger in size. Nodules are solid whereas cysts are fluid-filled
Six locations on the face and chest/upper back are graded according to the most severe lesion present, for example:
| Location | Type of lesion | Most severe lesion |
| Forehead | Comedones | Comedones |
| Right cheek | Comedones, papules | Papules |
| Left cheek | Papules, pustules | Pustules |
| Nose | Papules, nodules | Nodules/cysts |
| Chin | Papules, pustules, cysts | Nodules/cysts |
| Chest/upper back | Comedones, papules, pustules, nodules/cysts | Nodules/cysts |
Use this calculator to determine the GAGS score and chart the progress of acne treatment. Just enter the most severe lesion in each of the 6 locations and you will obtain the GAGS score and severity grading:
Other calculators:
- EASI (Eczema Area and Severity Index) calculator – for professional use
- EASI (Eczema Area and Severity Index) calculator for children under 8 years of age – for professional use
- MASI (Melasma Area and Severity Index) – for professional use
- mMASI (modified Melasma Area and Severity Index) – for professional use
- PASI (Psoriasis Area and Severity Index) – for professional use
- POEM (Patient Oriented Eczema Measure) – suitable for professional and patient use (after training)
- SCORAD (SCORing Atopic Dermatitis) – for professional use
- Skin type (Fitzpatrick Skin Type) – for professional and patient use