. Author manuscript; available in PMC: 2010 May 25.

Published in final edited form as: Biometrics. 2009 Apr 13;66(1):131–139. doi: 10.1111/j.1541-0420.2009.01238.x

Table 2.

An illustrative analysis of the time-varying effects of treatment on depression given time-varying suicidal ideation. Results are shown using the 2-Stage Regression Estimator β̂ and Robins’ Semi-parametric G-Estimator β̃.

2-Stage Estimator

Robins’ G-Estimator

Parameters of Interest

β̂

\hat{SE} (\hat{β})

Pr(> |z|)

β̃

\hat{SE} (\tilde{β})

Pr(> |z|)

A₁

β₁₀

0.236

0.418

0.57

0.194

0.446

0.66

A₁ : SSI₁

β₁₁

0.058

0.287

0.84

0.276

0.360

0.44

A₂

β₂₀

0.780

0.521

0.13

1.024

0.493

0.04

A_{2} : {\bar{SSI}}_{2}

β₂₁

−0.731

0.607

0.23

−1.395

0.598

0.02

A₃

β₃₀

−0.919

0.364

0.01

−1.053

0.350

< 0.01

A_{3} : {\bar{SSI}}_{3}

β₃₁

0.886

0.497

0.08

1.165

0.438

< 0.01