|Age and sex of participants, stratified by family role|
|Nind||% women||Mean age (sd)|
|Higher-order multiples (triplets/quadruplet)||155||70.3||25.9 (11.9)|
|Parents of twins||5,198||59.2||55.9 (8.1)|
|Non-twin siblings||1,898||63.4||38.3 (13.9)|
1 includes multiples without information on co-multiples (N=35), participants registered without any family members (N=16), spouses of siblings of twins (N=28), children of twins/siblings (N=288), and a spouse of a child of a twin (N=1).
Geels et al.
Geels et al. BMC Public Health 2013 13:207 doi:10.1186/1471-2458-13-207