Table 2.

Results of bivariate, multivariate, and stepwise logistic regressions: relative risks for a decline in higher-level ADLs by severe depression symptoms (bivariate and multivariate models) or by selected factors (stepwise model)

Depression symptoms	Total score	Social role	Intellectual activities	Instrumental self-maintenance
Severe depression symptoms (vs. not severe/none)—bivariate model	2.8 (1.5–5.1)	5.0 (2.6–9.6)	2.0 (0.9–4.6)	1.8 (0.9–3.8)
Severe depression symptoms (vs. not severe/none)—multivariate model	3.2 (1.6–6.3)	6.8 (3.1–14.8)	1.8 (0.75–4.4)	1.9 (0.9–4.2)
Explanatory variables selected by stepwise model
Severe depression symptoms (vs. not severe/none)	3.4 (1.74–6.5)	7.6 (3.6–16.1)	Not selected	2.2 (1.05–4.6)
Physical health (PCS scorea) = high (vs. low)			0.5 (0.26–0.97)

Values are given as the relative risk with the 95% confidence intervals (CI) given in parenthesis

Age, sex, and baseline TMIG-IC component score were forced to be included when stepwise variable selections were conducted

^aMOS SF-36 Physical Component Summary score, high score represents good health [8]