Table 2 

Design of randomised controlled trials and selected baseline characteristics of eligible trials of calcium supplements

TrialDesignCalcium dose (mg/d)DurationCare settingNo of participants*No in Ca/controls group†% womenMean age (y)
Recker 1977313 arm: Ca, HRT, control10402 yCommunity6022/2010057
Lamke 1978322 arm: Ca, P100012 moCommunity4019/1710060
Hansson 1987124 arm: 30 mg NaF/Ca, 10 mg NaF/Ca, Ca, P10003 yNS5025/2510066
Polley 1987174 arm: Ca, dairy, dairy/salt restrict, control10009 moCommunity26940/5210057
Riis 1987343 arm: Ca, HRT, P20002 yCommunity4314/1110051
Smith 1989352 arm: Ca, P15004 yCommunity16970/7710051
Dawson-Hughes 1990363 arm: Ca, Ca, P5002 yCommunity361158/9310058
Fujita 1990372 arm: Ca, control9002 yInstitution3212/2010080
Elders 1991393 arm: Ca, Ca, P1000 or 20002 yCommunity295198/97100NS
Prince 1991403 arm: Ca/ex, ex, HRT10002 yCommunity8039/4110057
Lau 1992422×2 factorial: Ca, Ca/ex, ex/P, P80010 moInstitution5027/2310076
Reid 1993432 arm: Ca v P10002 yCommunity13561/6110058
Strause 1994452×2 factorial: Ca, Ca/minerals, minerals, P10002 yCommunity11327/3210066
Prince 1995204 arm: Ca, Ca/ex, milk, P10002 yCommunity16842/4210063
Fujita 1996463 arm: Ca, Ca, P9002 yInstitution5838/2010081
Perez-Jaraiz 1996474 arm: Ca, HRT, calcitonin, control10001 yCommunity5226/2610050
Recker 1996482 arm: Ca, P12004.3 yCommunity19791/10010074
Ricci 1998512 arm: Ca, P10006 moCommunity4315/1610058
Riggs 1998522 arm: Ca, P16004 yCommunity236119/11710066
Storm 1998213 arm: Ca, milk, P10002 yCommunity4020/2010072
Castelo-Branco 1999223 arm: Ca, OHC, control25002 yCommunity6019/1610054
Ruml 1999532 arm: Ca, P8002 yCommunity6325/3110052
Fujita 2000544 arm: Ca, Ca, Ca, P9004 moNS3832/610055
Peacock 2000133 arm: Ca, 25OHD, P7504 yCommunity438126/1357274
Son 2001553 arm: Ca, alphacalcidiol, P100010 moCommunity6922/2110072
Albertazzi 2004263 arm: Ca, OHC, P5006 moCommunity15351/5010068
Prince 2006612 arm: Ca, P12005 yCommunity1460730/73010075
Reid 2006622 arm: Ca, P10005 yCommunity1471732/73910074
Manios 2007283 arm: Ca, dairy, control60012 moCommunity11226/3610062
Reid 2008653 arm: Ca, Ca, P600 or 12002 yCommunity323216/107056
Chailurkit 201067,682 arm: Ca, P5002 yCommunity404178/16510066
Nakamura 2012703 arm: Ca, Ca, P250 or 5002 yCommunity450281/13710060

Ca=calcium; HRT=hormone replacement therapy; P=placebo; ex=exercise; NaF=sodium fluoride; restrict=restriction; OMC=ossein-mineral complex; 25OHD=25-hydroxyvitamin D; NS=not stated.

*Total number of randomised participants in all treatment arms.

†Number of participants in relevant arms from trial in whom bone mineral density was reported.