Study participants

The New York City Neighborhood and Mental Health in the Elderly Study II is a 3-year longitudinal study of New York City (NYC) residents 65 to 75 years old at baseline, conducted from June 2011 to November 2013. Census tracts were divided into 16 strata, which represented varying degrees of racial-ethnic mix, household income, and walkability. Participants were sampled from a stratified geocoded telephone list from InfoUSA. In each participating household, interviewers asked how many people between 65 and 75 years of age lived in the household. In the case of two or more eligible household members, a computer-assisted telephone-interviewing programme randomly selected a household member based on age and sex, e.g. the oldest female in the household. Each telephone number in each neighbourhood had an equal probability of being selected. At baseline, there were 3,497 respondents. The response rate for Wave-1 was 17% and the cooperation rate was 30%. At wave-2, 2,455 were successfully re-interviewed (follow-up rate of 78%) and at wave-3 2,355 were successfully re-interviewed (follow-up rate of 67%). Respondents were offered $10 for participating. The study was approved by the Institutional Review Boards of Columbia University, New York Academy of Medicine, and Abt SRBI.

Additional details regarding the methods are available in Appendix Text 1 in the supplementary data on the journal website (http://www.ageing.oxfordjournals.org/).