<qa>  What is the skin condition that would interfere with the diagnosis or assessment of acne vulgaris?4. Patient has a skin condition that would interfere with the diagnosis or assessment of acne vulgaris e.g., on the face: rosacea, dermatitis, psoriasis, squamous cell carcinoma, eczema, acneform eruptions caused by medications, steroid acne, steroid folliculitis, bacterial folliculitis. 