| Cases | Cases of adults (18 or older) with psoriasis were consecutively recruited from outpatient clinic of the study hospital.
Diagnosis of psoriasis was made based on dermatological and histopathological evaluation.
Exclusion criteria included the presence of other systemic diseases likely to have ocular involvement, history of eye surgery, eye trauma, primary eye diseases, and wearing contact lenses. | Cases of adults (18 years or older) with psoriasis were identified from the database of a German nationwide statutory health insurance entity named Gmuender Ersatzkasse that covered 1.6 million individuals. The database of the year 2009 was used.
Diagnosis of psoriasis was made based on the presence of diagnostic codes of psoriasis. | Cases with psoriasis who were followed by the dermatology clinic of the study hospital were enrolled.
Exclusion criteria included prior ocular surgery, retinal or choroidal pathology, high myopia and hypermetropia, best-corrected visual acuity less than 20/25, systemic disease (hypertension, diabetes mellitus, cerebrovascular disease, peripheral vascular disease, pregnancy, or lactation), and history of systemic treatment for psoriasis. | Cases with psoriasis were recruited from the outpatient clinic at the Faculty of Medicine, Alexandria University, Alexandria, Egypt
Exclusion criteria included inflammatory connective tissue diseases, diabetes, nephropathy, lung and heart disease, gastroenterological disease/inflammatory bowel disease, neurological disease, neoplasia, metabolic bone disease, skin diseases other than psoriasis, infections, hematological disease, liver disease, previous ocular surgery, active eye infection, or active ocular allergy. | Cases of adults (18 years or older) with psoriasis were recruited from two dermatology centers from September 2014 to January 2017.
Exclusion criteria included diabetes mellitus, hypertension, hyperlipidemia, thyroid disorders, hepatic or renal insufficiency, rheumatoid arthritis, gout, collagen vascular diseases, atopic dermatitis, rosacea, other chronic inflammatory diseases, pregnant or lactating women, smokers, contact lens wearers, use of anticholinergics, history of eye trauma or surgery, optic neuritis, glaucoma, radiotherapy, malignancy or chronic infection of the lacrimal glands, human immunodeficiency virus, and hepatitis B or C virus infections. |
| Comparators | Comparators without psoriasis and with healthy first-degree relatives were consecutively recruited from the same center. | Comparators were the rest of patients in the database who did not carry the diagnostic codes of psoriasis | Comparators were individuals without psoriasis who were admitted to the outpatient Clinic of Ophthalmology for minor refractive errors. They were gender- and age-matched to cases. | Comparators were individuals without psoriasis who were seen at the same clinic. They were gender- and age-matched to cases. | Comparators without psoriasis were recruited from the same centers. |
