title: A population-based study of 18-year old Swedish youths and factors correlated with their total number of lifetime sexual partners.
abstract: The number of sexual partners has in studies been shown to be a factor correlated with STI but there is little published knowledge on what factors are associated with number of sexual partners.
  
  
  OBJECTIVE
  To examine which variables are correlated with the number of lifetime sexual partners (NLSP) among youths.
  
  
  METHODS
  All 18-year old girls and boys in four cities in northern Sweden.
  
  
  METHODS
  A population-based study where participants answered a questionnaire regarding their social lifestyle, psychological and sexual health. The associations between these independent variables and the dependent variable (NLSP) were investigated by multivariate linear regression analysis.
  
  
  RESULTS
  The boy and girl median NLSP was 2.0 (P25 =1.0, P75=3.0). The final model explained 29% of the total boy NLSP variation and 46% of the total girl NLSP variation. Eight boy variables and thirteen girl variables significantly correlated with NLSP were found. The two strongest variables associated with increased NLSP among boys and girls, was feelings of guilt or shame after sex and smoking regularly. Variables prior associated with an increased risk of acquiring STI's were associated with increased NLSP. The study found new gender differed behaviour variables correlated to NLSP not previously considered to be risk factors for STI.
  
  
  CONCLUSIONS
  To prevent the spread of STI it is important that persons with many partners are identified, treated if necessary and possible, or encouraged to change their behaviour. The study found several boy and girl variables associated with increased NLSP, which could facilitate both primary- and secondary preventions.
authors.affiliation: Department of Public Health and Clinical Medicine, Family Medicine, University of Umeå, Umeå, Sweden.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Novak
authors.forename: Roger B
authors.initials: RB
authors.lastname: Karlsson
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D016497:Adolescent Health Services; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D008297:Male; D012737:Sex Factors; D012725:Sexual Behavior / Q000523:psychology*; D012747:Sexual Partners / Q000523:psychology*; D012749:Sexually Transmitted Diseases / Q000517:prevention & control* / Q000523:psychology; D011795:Surveys and Questionnaires; D013548:Sweden