Objectives: The primary aim was to assess the age-related changes that occur in older women. This paper describes the study rationale and methods, recruitment, and retention strategies.
Methods: The Longitudinal Assessment of Women (LAW) Study was a longitudinal, observational, and multidisciplinary evaluation of a population-based cohort of urban-living women, aged between 40 and 80 years at recruitment and randomly invited from a district in Brisbane (a city in Australia) via the electoral roll. Five hundred eleven women were recruited and stratified into four age groups (40–49, 50–59, 60–69, 70–79 years) and were assessed on three or four occasions each year, using interviews and diagnostic instruments (echocardiography, applination tonometry, dual-energy x-ray absorptiometry [DEXA]) Retention strategies included flexibility, accessibility, personalized attention, and feedback.
Results: From a sample frame of 1598 names, there were 1082 respondents, of whom 511 (47%) were successfully recruited from those eligible to participate. Recruitment was quickest for the oldest age group, 70–79 years, and slowest for the age group 40–49 years; all age groups achieved their required quota. A scheduling program was developed to minimize the number of visits and maximize the use of allocated time. The largest dropout was seen in year 1 of the study, with very few thereafter. Of the 9 deaths, cancer was the cause in 7. The retention rate after 5 years was 95.5%.
Conclusions: The design of the present study, with careful attention to coordination and a personal approach, facilitated the completion of a 5-year study, enabling a collection of a set of wide-ranging data from almost all the women recruited. The information thus collected will form the basis of cross-linking analysis of the risk factors associated with health problems in aging women.
