Psoriasis covers≥5–10% of the skin's surface area?
Psoriasis impairs working or functional capacity of the patient?
Psoriasis significantly lowers the patient's quality of life?
The patient has psoriatic arthropathy?

YES
on any of the items

NO
on every item

No systemic treatment nor phototherapy → choose topical treatment

End

Consider phototherapy or systemic treatment

Consider systemic treatment

The patient has psoriatic arthropathy?
The patient has earlier needed systemic treatment?
Phototherapy is contra-indicated, not effective or not available?

YES
on any of the items

NO
on every item