Rapid Responses to:

NEWS: Clare Dyer Claim launched against makers of third generation pill BMJ 2002; 324: 561 [Full text]

Rapid Responses: Submit a response to this article

Rapid Responses published:

Simple association doesn't always mean causation

Anusch Yazdani   (9 March 2002)

Factor V (Leiden) and D-Dimer(ELISA) to assess the risk of thrombosis.

Friedrich Flachsbart   (11 March 2002)

Simple association doesn't always mean causation 9 March 2002
Anusch Yazdani, Gynaecologist Mater Hospital, Brisbane Send response to journal: Re: Simple association doesn't always mean causation	I wonder what the implications of this action are for the use of Implanon... Etonogestel, the active component in Implanon, is the biologically active metabolite of desogestrel, the progestogen of one of the oral contraceptives implicated in this class action. The recent meta- analysis by Kemmeren et al (BMJ 2001 Jul 21;323(7305):131-4) suggests an overall adjusted odds ratio for third versus second generation oral contraceptives of 1.7 for deep venous thrombosis. Kemmeren et al (Thromb Haemost 2002 Feb;87(2):199-205)attribute this increased risk to a less effective compensation of the thrombotic effect of ethinylestradiol by desogestrel and desogestrel per se may therefore be vindicated. Unfortunately, legal action is not always based on sound scientific evidence and this simple association may demand further caution.
Factor V (Leiden) and D-Dimer(ELISA) to assess the risk of thrombosis. 11 March 2002
Friedrich Flachsbart, general medicine 37085 Göttingen Send response to journal: Re: Factor V (Leiden) and D-Dimer(ELISA) to assess the risk of thrombosis.	Dear Sir, In cases of thrombosis in the patient's family You should search for a genetic mutation like Factor V (Leiden). Any symptoms of minor pulmonary embolism should at once induce D- Dimer(ELISA)-testing to exclude deep-vein-thrombosis. This is the only way to minimize the risk! Sincerely Yours Friedrich Flachsbart