In a 2017 study by Zaslavsky et al., the authors derived biomarker-calibrated dietary energy and protein intakes to address dietary self-report errors. Using these data, they then evaluated the association of mortality in older women with frailty and dietary intake and healthy diet indexes, such as the alternate Mediterranean Diet (aMED), the Dietary Approaches to Stop Hypertension (DASH) score, and the Dietary Inflammatory Index (DII). The analytic sample included 10,034 women aged 65-84 y with frailty and complete dietary data from the Women's Health Initiative Observational Study. A food-frequency questionnaire collected the dietary data.

1. What covariates are controlled for in model 1 and model 2, respectively?
2. Isthep-for trend significant? What does this tell us about the association?