1. Department of Preventive Medicine and Public Health; School of Medicine; University of Navarra; Pamplona Spain
2. Institute for Culture and Society; University of Navarra; Pamplona Spain
3. School of Public Health; University of Bielefeld; Bielefeld Germany
4. Department of Clinical Medicine; Bremen Institute for Prevention Research and Social Medicine; Bremen Germany
5. Department of Education; University of Navarra; Pamplona Spain
6. Obstetrics and Gynecology; University of Navarra Hospital; Pamplona Spain