title: Temporal case clustering in pityriasis rosea: a regression analysis on 1379 patients in Minnesota, kuwait, and diyarbakir, Turkey.
abstract: OBJECTIVE
  To detect temporal case clustering in patients with pityriasis rosea in different geographic locations.
  
  
  METHODS
  Regression analysis of dates on which 1379 patients were diagnosed as having pityriasis rosea in 3 different geographic locations. The control data consisted of dates of diagnosis of patients with psoriasis in the same settings.
  
  
  METHODS
  Dermatology clinics in Kuwait, Minnesota, and Diyarbakir, Turkey.Patients Patients with pityriasis rosea and psoriasis seeking care in the clinics.
  
  
  RESULTS
  Three significant positive clusters (P = .005, P =.001, and P =.01, respectively) and 1 significant negative cluster (P<.001) were detected in these series of patients. No cluster was detected in 2 corresponding series of patients with psoriasis in Kuwait and Turkey.
  
  
  CONCLUSIONS
  Temporal case clustering exists in pityriasis rosea.
authors.affiliation: Department of Medicine, University of Hong Kong and Queen Mary Hospital, Pokfulam, Hong Kong. achuh@iohk.com
authors.forename: Antonio A T
authors.initials: AA
authors.lastname: Chuh
authors.forename: Nicolas
authors.initials: N
authors.lastname: Molinari
authors.forename: Gabriel
authors.initials: G
authors.lastname: Sciallis
authors.forename: Mehmet
authors.initials: M
authors.lastname: Harman
authors.forename: Sedat
authors.initials: S
authors.lastname: Akdeniz
authors.forename: Arti
authors.initials: A
authors.lastname: Nanda
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002648:Child; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D015994:Incidence; D007730:Kuwait / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D017515:Pityriasis Rosea / Q000175:diagnosis* / Q000453:epidemiology*; D011336:Probability; D012044:Regression Analysis; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution; D014421:Turkey / Q000453:epidemiology