Figure 1.

Sample selection criteria and procedure. ^a The sample is limited to those aged 35 years and older. ^bExcluded were (i) caregivers of a family member or friend other than a spouse, child, parent, or sibling; (ii) caregivers who provided care less than 4 weeks and/or less than 1 hour per week; (iii) unmarried spouse caregivers; and (iv) noncaregivers during the past 12 months but who had been caregivers in the past more than 12 months ago. CG = caregiver; non-CG = noncaregiver.