BACKGROUND: The strength of the association between undescended testis and testicular cancer varies considerably across studies. Here we report the effect of various classifications of self-reported history of undescended testis and different data sources on the estimates of the risk of testicular cancer from a case-control study. METHODS: We performed a population-based case-control study including 269 testicular cancer cases and 797 controls matched on age and region. Medical history was assessed by interviews (index persons) and mailed questionnaires (mothers). We used conditional logistic regression to calculate odds ratios (OR) and kappa coefficients to assess agreement between different sources of information. RESULTS: Odds ratios for testicular cancer ranged between 2.4 and 5.4 based on the sons' self-reports and between 1.1 and 1.9 based on the mothers' reports. The agreement between the sons and mothers on undescended, gliding or retractile testis was fair (kappa 0.53) and was good when these conditions were treated by surgery (kappa 0.89). The rating of a history of undescended testis by two urologists was fair (kappa 0.54). CONCLUSIONS: The questionnaire design, the classifications of undescended testis and data sources have an important impact on the OR for the association of undescended testis and testicular cancer. These factors may partially explain the heterogeneity of the OR for this association in case-control studies relying on self-reports.
BACKGROUND: The strength of the association between undescended testis and testicular cancer varies considerably across studies. Here we report the effect of various classifications of self-reported history of undescended testis and different data sources on the estimates of the risk of testicular cancer from a case-control study. METHODS: We performed a population-based case-control study including 269 testicular cancer cases and 797 controls matched on age and region. Medical history was assessed by interviews (index persons) and mailed questionnaires (mothers). We used conditional logistic regression to calculate odds ratios (OR) and kappa coefficients to assess agreement between different sources of information. RESULTS: Odds ratios for testicular cancer ranged between 2.4 and 5.4 based on the sons' self-reports and between 1.1 and 1.9 based on the mothers' reports. The agreement between the sons and mothers on undescended, gliding or retractile testis was fair (kappa 0.53) and was good when these conditions were treated by surgery (kappa 0.89). The rating of a history of undescended testis by two urologists was fair (kappa 0.54). CONCLUSIONS: The questionnaire design, the classifications of undescended testis and data sources have an important impact on the OR for the association of undescended testis and testicular cancer. These factors may partially explain the heterogeneity of the OR for this association in case-control studies relying on self-reports.
Authors: Michael B Cook; Olof Akre; David Forman; M Patricia Madigan; Lorenzo Richiardi; Katherine A McGlynn Journal: Int J Epidemiol Date: 2010-07-26 Impact factor: 7.196
Authors: Cornelia Baumgardt-Elms; Michael Schümann; Wolfgang Ahrens; Katja Bromen; Andreas Stang; Ingeborg Jahn; Christa Stegmaier; Karl-Heinz Jöckel Journal: Int Arch Occup Environ Health Date: 2004-12-07 Impact factor: 3.015
Authors: Nils Schmeisser; David I Conway; Andreas Stang; Ingeborg Jahn; Christa Stegmaier; Cornelia Baumgardt-Elms; Karl-Heinz Jöckel; Thomas Behrens; Wolfgang Ahrens Journal: BMJ Open Date: 2013-09-20 Impact factor: 2.692
Authors: Kimberly Banks; Ellenie Tuazon; Kiros Berhane; Chester J Koh; Roger E De Filippo; Andy Chang; Steve S Kim; Siamak Daneshmand; Carol Davis-Dao; Juan P Lewinger; Leslie Bernstein; Victoria K Cortessis Journal: Front Endocrinol (Lausanne) Date: 2013-02-18 Impact factor: 5.555