title: Age-related changes relevant to health in women: design, recruitment, and retention strategies for the Longitudinal Assessment of Women (LAW) study.
abstract: OBJECTIVE
  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.
authors.affiliation: Betty Byrne Henderson Women's Health Research Centre, University of Queensland, Royal Brisbane and Women's Hospital, Australia. s.khoo@uq.edu.au
authors.forename: Soo Keat
authors.initials: SK
authors.lastname: Khoo
authors.forename: Sheila
authors.initials: S
authors.lastname: O'Neill
authors.forename: Catherine
authors.initials: C
authors.lastname: Travers
authors.forename: Brian
authors.initials: B
authors.lastname: Oldenburg
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D001315:Australia; D015331:Cohort Studies; D004452:Echocardiography; D005260:Female; D006304:Health Status; D006801:Humans; D008137:Longitudinal Studies; D008365:Manometry; D008487:Medical History Taking / Q000379:methods; D008875:Middle Aged; D018579:Patient Selection; D012107:Research Design; D016387:Women's Health