As can been seen in table below, all but one of the 12 assessments conducted since birth have enjoyed participation rates well above 90 % (Table 1).Table 1Retention in the Dunedin StudyAgeYearNumberPercenta (%)Birth1972–197331975–1976103710051977–19789919671979–19809549291981–198295592111983–198492590131985–198685082151987–198897695181990–199199397211993–199499297261998–199998096322004–200597296382010–201296195 a% of living Study members
