Article History
Accepted: 6 September 2018
First Online: 12 September 2018
Compliance with ethical standards
:
: The authors declare no conflict of interest.
: The study was conducted according to the guidelines set out in the 1964 Helsinki Declaration and its later amendments. Ethical approval for TILDA was granted by the Faculty of Health Sciences Research Ethics Committee of Trinity College Dublin.
: Informed consent was obtained from all individual participants included in the study.