title: Incidence and predictors of annual chlamydia testing among 15-29 year olds attending Aboriginal primary health care services in New South Wales, Australia.
abstract: BACKGROUND
  For the past two decades, chlamydia has been the most commonly notified infectious disease among young people (15-29 year olds) in Australia, the United States of America and the United Kingdom and rates have increased annually in these three countries. In Australia, rates of chlamydia are three times higher in Aboriginal compared with non-Aboriginal people. Australian sexually transmissible infection guidelines recommend annual chlamydia testing for 15-29 year old females and males. This analysis will examine the incidence and predictors of annual chlamydia testing in 15-29 year olds attending four Aboriginal Community Controlled Health Services (ACCHS) in Australia.
  
  
  METHODS
  From 2009-2011, attendance and chlamydia testing data were extracted from the patient system to calculate the number and proportion of 15-29 year olds that were tested for chlamydia and that tested positive for chlamydia by gender (male, female), age-group (15-19, 20-24, 25-29 years), Aboriginal status (Aboriginal, non-Aboriginal people) and by the four ACCHSs sites (1, 2, 3 and 4). A cohort was created to calculate the incidence rate per 100 person-years (PY) and predictors of an annual chlamydia test (a test within 12-months of a previous test/visit) by the above factors using Cox regression. Unadjusted and adjusted hazard ratios (AHR) and their 95 % confidence intervals (CIs) and p-values were calculated with significance at p < 0.05.
  
  
  RESULTS
  From 2009-2011, there were 2896 individuals who attended the four ACCHSs. Overall , 17 % (22 % of females and 10 % of males) were tested for chlamydia and 9 % tested positive (8 % of females and 14 % of males). The median time to an annual chlamydia test was 10.7 months. The cohort included 2318 individuals. Overall the incidence rate of an annual chlamydia test was 9.1 per 100 PY (11.6 in females and 5.8 in males). Predictors of an annual chlamydia test were being female (AHR: 1.7, 95 % CI: 1.2-2.2, p < 0.01), being 15-19 years old (AHR: 1.6, 95 % CI: 1.1-2.3, p < 0.01) and attending ACCHS site 2 (AHR: 3.8, 95 % CI: 1.8-8.0, p < 0.01).
  
  
  CONCLUSIONS
  This analysis highlights that opportunistic STI testing strategies are needed to increase annual chlamydia testing in young people; especially males.
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. simon.graham@unimelb.edu.au.|Centre for Epidemiology and Biostatistics, School of Population and Global Health, University of Melbourne, Melbourne, VIC, 3052, Australia. simon.graham@unimelb.edu.au.
authors.forename: Simon
authors.initials: S
authors.lastname: Graham
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. rguy@kirby.unsw.edu.au.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Guy
authors.affiliation: South Australian Health and Medical Research Institute, Adelaide, SA, 5000, Australia. james.ward@sahmri.com.
authors.forename: James S
authors.initials: JS
authors.lastname: Ward
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. jkaldor@kirby.unsw.edu.au.
authors.forename: John
authors.initials: J
authors.lastname: Kaldor
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. bdonovan@kirby.unsw.edu.au.|Sydney Sexual Health Centre, Sydney Hospital, Sydney, NSW, 2000, Australia. bdonovan@kirby.unsw.edu.au.
authors.forename: Basil
authors.initials: B
authors.lastname: Donovan
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. Janet.knox@ncahs.health.nsw.gov.au.
authors.forename: Janet
authors.initials: J
authors.lastname: Knox
authors.affiliation: Aboriginal Community Controlled Health Service, New South Wales, NSW, Australia. DMcCowen@armajun.org.au.
authors.forename: Debbie
authors.initials: D
authors.lastname: McCowen
authors.affiliation: Aboriginal Community Controlled Health Service, New South Wales, NSW, Australia. patriciab@wachs.net.au.
authors.forename: Patricia
authors.initials: P
authors.lastname: Bullen
authors.affiliation: Aboriginal Community Controlled Health Service, New South Wales, NSW, Australia. jbooker@illawarraams.com.au.
authors.forename: Julie
authors.initials: J
authors.lastname: Booker
authors.affiliation: Aboriginal Community Controlled Health Service, New South Wales, NSW, Australia. cobrien@illawarraams.com.au.
authors.forename: Chris
authors.initials: C
authors.lastname: O'Brien
authors.affiliation: Aboriginal Community Controlled Health Service, New South Wales, NSW, Australia. Kristine.Garrett@galambila.org.au.
authors.forename: Kristine
authors.initials: K
authors.lastname: Garrett
authors.affiliation: Kirby Institute, UNSW Australia, Sydney, NSW, 2052, Australia. hwand@kirby.unsw.edu.au.
authors.forename: Handan C
authors.initials: HC
authors.lastname: Wand
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002690:Chlamydia Infections / Q000453:epidemiology* / Q000208:ethnology; D003153:Community Health Services / Q000706:statistics & numerical data; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D009517:New South Wales / Q000453:epidemiology / Q000208:ethnology; D011320:Primary Health Care / Q000706:statistics & numerical data; D017678:Sex Distribution; D055815:Young Adult