Fig. 1

Causal structure of long-term care needs with socio-economic status (SES) and physical health for the elderly men. There are nine observed endogenous variables [educational level, annual income, basic activities of daily living (BADL) score in 2004, instrumental activities of daily living (IADL) score in 2001, frequency of going out in 2001, BADL score in 2004, IADL score in 2004, frequency of going out in 2004, and long-term care needs in 2004], two unobserved endogenous variables (physical healthy in 2001 and physical health in 2004), and 12 unobserved exogenous variables (SES in 2001, d1, d2, z1, z2, e1, e2, e3, e4, e5, e6, e7). Arrows indicate their significant associations and their directions between variables, double curved arrows indicates correlation between each factor. This model fit the data well with the high goodness of fit indexes which are showed in the figure. The long-term care (LTC) needs of elderly men are well explained by the three latent variables (R ² = 0.70). NFI Normalized Fit Index, CFI Comparative Fit Index, RMSEA root mean square error of approximation, CMIN chi-square (χ²)