2014, linked to the National Death Index (NDI), with follow-up to the date of death or 31 December 2015[^2]. An estimated 95.4% of baseline participants had the eligible mortality follow-up information. The NCHS at the Centers for Disease Control and Prevention used post-stratification re-weighting based on the U.S. population to account for ineligible follow-up[^3]. The NDI file provides data on the mortality status, year of death, quarter of year, and cause of death (categorized into the following groups based on ICD-9 and ICD-10 codes – heart disease, cancer, chronic lower respiratory disease, cerebrovascular diseases, diabetes, pneumonia and influenza, Alzheimer’s disease, kidney disease, and unintentional injuries).

Study Population {#sec:spop}
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A total of 282,001 adults aged 18 years and above were interviewed between 2002-2011, of which we excluded those with missing information on their mortality follow-up ($n=12,905$) resulting in a study sample of $n=269,069$ individuals

Outcome Definition {#sec:outcome}
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Our outcome of interest was death within 4 years of the date of interview. We used 16 quarters of a year from the quarter of the interview to the quarter of death as our follow-up time, as the NHIS Linked Mortality files provides the year and quarter of death only.

Candidate Variables 