13 trials - CSPPT - VITATOPS - WAFACS - WENBIT (folic ac,B12) - SEARCH - HOPE-2 (Lonn) - NORVIT (folic acid + B12) (Bonaa) - NORVIT (folic acid, B12 and vit B6) (Bonaa) - FOLARDA (Liem) - VISP (Toole) - GOES (Liem) - CHAOS-2 - SU.FOL.OM3
2 trials - VITATOPS - VISP (Toole)