1. Research Centre Primary/Secondary Health Care, Vrije Universiteit Amsterdam,The Netherlands
2. Institute for Endocrinology, Reproduction and Metabolism, Vrije Universiteit, Amsterdam Amsterdam, The Netherlands
3. Department of Medical Psychology, Vrije Universiteit, Amsterdam Amsterdam, The Netherlands
4. Amsterdam Thrombosis Service and Laboratory for General Practitioners, Vrije Universiteit, Amsterdam Amsterdam, The Netherlands
5. Department of Epidemiology and Biostatistics, Vrije Universiteit, Amsterdam Amsterdam, The Netherlands