Table 1.

Sample Size by Number of Visits^*

Number of Visits	n (% of Sample)
1	538 (100.0)
2	350 (65.1)
3	208 (38.7)
4	88 (16.4)
5	30 (5.6)
6	6 (1.1)
7	3 (0.6)
8	2 (0.4)

^*The BLSA is not a fixed cohort; the study uses rolling recruitment. Thus, what appears as attrition are participants who were not in the study long enough for higher numbers of visits.