[1] Gen Hosp Trikala, Dept Obstet & Gynecol, Trikala 42100, Greece
[2] European Univ Cyprus, Med Sch, Dept Hlth Sci, CY-2404 Nicosia, Cyprus
[3] Norfolk & Norwich Univ Hosp, Clin Oncol Dept, Norwich NR4 7UY, Norfolk, England
[4] Natl & Kapodistrian Univ Athens, Med Sch, Dept Hyg Epidemiol & Med Stat, Athens 15772, Greece