Table 1.
Characteristics of eight studies in the InterLACE consortium
| Study | Country | N | Age at baseline Median (IQR) |
Survey (year) selected for analytic baselinea |
Survey (year) selected for three-year follow up |
|---|---|---|---|---|---|
| Australian Longitudinal Study on Women’s Health (ALSWH) | Australia | 10,323 | 50 (48, 51) | Survey 2 (1998) | Survey 3 (2001) |
| National Survey of Health and Development (NSHD) | UK | 1,068 | 50a | Survey 1996 (1996) | Survey 1999 (1999) |
| National Child Development Study (NCDS) | UK | 3,983 | 50a | Survey 8 (2008) | N/A |
| Study of Women’s Health Across the Nation (SWAN) | USA | 2,345 | 50 (48, 52) | Visit 4 (2000–2002) | Visit 7 (2003–2005) |
| Whitehall II Study (WHITEHALL) | UK | 2,041 | 50 (45, 55) | Survey 3 (1991–1994) | Survey 4 (1995–1996) |
| Seattle Midlife Women’s Health Study (SMWHS) | USA | 189 | 50 (46, 53) | Survey 2000 (2000) | N/A |
| Healthy Ageing of Women Study (HOW) | Australia | 768 | 54 (52, 57) | Survey 1 (2001) | N/A |
| Japanese Midlife Women’s Health Study (JMWHS) | Japan | 743 | N/Ab | Survey 1 (2002) | N/A |
| Overall | 21,460 | 50 (49, 51) |
N/A, not applicable; IQR, interquartile range.
a
For the longitudinal studies, data for women around the age of 50 years were used as analytic baseline to make the data more comparable across studies. Women who participated in the NSHD (1946 British birth cohort) and NCDS (1958 British birth cohort) were at age 50 years in the 1996 and 2008 survey, respectively.
b
JMWHS provided age by category only (≤55 and >55 years), and 48% of women were aged more than 55 (age range from 45 to 60 years).