Table 3

Result of IV-Cox analysis

  IV-Cox
Second stage
Dependent variable: incidence of functional disability
First stage
Dependent variable: number of participations
HRCoefficient
Endogenous variableParticipation (log-transformation)0.50 (0.34 to 0.74)**
Exogenous variableNumber of community salons within a radius of 350 m from the subject's home0.04 (0.01 to 0.06)**
SexFemale (reference: male)9.00 (3.62 to 22.41)***0.15 (0.12 to 0.18)***
Age75 years and over (reference: 65–74 years)7.29 (5.48 to 9.70)***0.03 (−0.01 to 0.06)
Educational attainment9 years and under (reference: 10 years and over)1.18 (0.93 to 1.51)0.02 (−0.01 to 0.05)
Equivalent income¥1.99 million and less (reference: ¥2 million and more)2.21 (1.55 to 3.16)***0.05 (0.02 to 0.08)**
Higher level of ADL12 points and under (reference: 13 points)0.50 (0.31 to 0.81)**−0.07 (−0.10 to −0.03)***
DepressionNone (reference)
Mild0.92 (0.68 to 1.24)−0.03 (−0.06 to 0.01)
Severe4.63 (2.87 to 7.48)***0.04 (0.01 to 0.06)**
ConstantConstant−0.11 (−0.17 to −0.06)*
  • In the first-stage regression of 2SLS, F-statistics was 20.07 (p<0.001), and partial R2 was 0.06.

  • *p<0.05, **p<0.01, ***p<0.001.

  • IV, instrumental variable.