{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T18:45:12Z","timestamp":1757616312112,"version":"3.44.0"},"reference-count":7,"publisher":"BMJ","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Fam Plann Reprod Health Care"],"published-print":{"date-parts":[[2010,4]]},"DOI":"10.1783\/147118910791069376","type":"journal-article","created":{"date-parts":[[2010,4,8]],"date-time":"2010-04-08T19:26:02Z","timestamp":1270754762000},"page":"103.1-103","source":"Crossref","is-referenced-by-count":7,"title":["Risk of VTE among users of oral contraceptives"],"prefix":"10.1136","volume":"36","author":[{"given":"Samuel","family":"Shapiro","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juergen","family":"Dinger","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2010,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1783\/147118910790291037","article-title":"Risk of venous thromboembolism among users of oral contraceptives: a review of two recently published studies","volume":"36","author":"Shapiro, S.; Dinger, J.","year":"2010","unstructured":"Shapiro S, Dinger J. Risk of venous thromboembolism among users of oral contraceptives: a review of two recently published studies. J Fam Plann Reprod Health Care 2010; 36: 33\u201338.","journal-title":"J Fam Plann Reprod Health Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2890","DOI":"10.1136\/bmj.b2890","article-title":"Hormonal contraception and risk of venous thromboembolism: national follow-up study","volume":"339","author":"Lidegaard, \u00d8.; L\u00f8kkegaard, E.; Svendsen, A.L.; Agger, C.","year":"2009","unstructured":"Lidegaard \u00d8, L\u00f8kkegaard E, Svendsen AL, Agger C. Hormonal contraception and risk of venous thromboembolism: national follow-up study. BMJ 2009; 339: b2890.","journal-title":"BMJ"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2921","DOI":"10.1136\/bmj.b2921","article-title":"Effects of oestrogen dose and progestogen type on venous thrombotic risk associated with oral contraceptives: results of the MEGA case-control study","volume":"339","year":"2009","unstructured":"Van Hylckama Vlieg A, Helmerhorst FM, Vandenbroucke JP, Doggen CJM, Rosendaal FR. Effects of oestrogen dose and progestogen type on venous thrombotic risk associated with oral contraceptives: results of the MEGA case-control study. BMJ 2009; 339: b2921.","journal-title":"BMJ"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1016\/j.jclinepi.2009.03.018","article-title":"Venous thromboembolism discharge diagnoses in the Danish National Patient Registry should be used with caution","volume":"63","author":"Severinsen, M.T.; Kristensen, SR, Overvad; K, Dethlefsen; C, Tj\u00f8nneland; A, Johnsen; S.P.","year":"2010","unstructured":"Severinsen MT, Kristensen SR, Overvad K, Dethlefsen C, Tj\u00f8nneland A, Johnsen SP. Venous thromboembolism discharge diagnoses in the Danish National Patient Registry should be used with caution. J Clin Epidemiol 2010; 63: 223\u2013228","journal-title":"J Clin Epidemiol"},{"key":"ref_5","unstructured":"Critique of a Danish cohort study on hormonal contraception and VTE Thanks to Samuel Shapiro and J\u00fcrgen Dinger (S&D) for their altruistic interest in and concern for possible bias and confounding in two recently published studies on use of oral contraceptives (OCs) and the risk of venous thromboembolism (VTE), as detailed in their review article1 in the January 2010 issue of the Journal of Family Planning and Reproductive Health Care. One of the two studies under discussion was a national Danish cohort study.2","article-title":"Critique of a Danish cohort study on hormonal contraception and VTE Thanks to Samuel Shapiro and J\u00fcrgen Dinger (S&D) for their altruistic interest in and concern for possible bias and confounding in two recently published studies on use of oral contraceptives (OCs) and the risk of venous thromboembolism (VTE), as detailed in their review article1 in the January 2010 issue of the Journal of Family Planning and Reproductive Health Care. One of the two studies under discussion was a national Danish cohort study.2"},{"key":"ref_6","unstructured":"Confounding Next S&D argue that our missing control for obesity (BMI) \u201cwas a major defect in the Danish study\u201d. Now, adiposity is a well-established risk factor for VTE. A risk factor is, however, not the same as a confounder, which in addition to being a risk factor also has to be associated with use of OCs in general, and differentially with different OC types, if the considerations of S&D are to be valid. The fact is that there is no association between OC use and adiposity, and no significant difference in the frequency of adiposity in users of different types of OC (as documented in our paper).2 Therefore, the increased risk of VTE in users of OC with thirdand fourth-generation OCs as compared with OCs containing LNG cannot be explained by our missing control for adiposity.","article-title":"Confounding Next S&D argue that our missing control for obesity (BMI) \u201cwas a major defect in the Danish study\u201d. Now, adiposity is a well-established risk factor for VTE. A risk factor is, however, not the same as a confounder, which in addition to being a risk factor also has to be associated with use of OCs in general, and differentially with different OC types, if the considerations of S&D are to be valid. The fact is that there is no association between OC use and adiposity, and no significant difference in the frequency of adiposity in users of different types of OC (as documented in our paper).2 Therefore, the increased risk of VTE in users of OC with thirdand fourth-generation OCs as compared with OCs containing LNG cannot be explained by our missing control for adiposity"},{"issue":"2","key":"ref_7","article-title":"Fam Plann Reprod","volume":"36","author":"FSRH, J.","year":"2010","unstructured":"\u00a9FSRH J Fam Plann Reprod Health Care 2010: 36(2)","journal-title":"Health Care"}],"container-title":["Journal of Family Planning and Reproductive Health Care"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1783\/147118910791069376","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T18:02:31Z","timestamp":1757095351000},"score":1,"resource":{"primary":{"URL":"https:\/\/jfprhc.bmj.com\/lookup\/doi\/10.1783\/147118910791069376"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,4]]},"references-count":7,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2010,4,1]]},"published-print":{"date-parts":[[2010,4]]}},"alternative-id":["10.1783\/147118910791069376"],"URL":"https:\/\/doi.org\/10.1783\/147118910791069376","relation":{},"ISSN":["1471-1893","2045-2098"],"issn-type":[{"type":"print","value":"1471-1893"},{"type":"electronic","value":"2045-2098"}],"subject":[],"published":{"date-parts":[[2010,4]]}}}