[Mediation-information] interpretation for mediation effect

[Weichao Bao]

Dear All,


I am using the mediation package on my research. The outcome is dichotomous
and the treatment is continuous. It was run with GAM model.  But I am
confused with the following results. It shows all the Mediation
Effect_0, Mediation Effect_1,and Mediation Effect (Average) have significant
mediation effect based on 95% CI. However, the Proportion of Total Effect
via Mediation_0, Proportion of Total Effect via Mediation_1, and Proportion
of Total Effect via Mediation (Average) indicate there is no mediation at
all based on the 95% confidence interval.  The result is:


Mediation Effect_0:  -0.004309 95 % CI  -0.0086640 -0.0007235

Mediation Effect_1:  -0.006557 95 % CI  -0.014173 -0.001015

Direct Effect_0:  0.04452 95 % CI  0.001001 0.112969

Direct Effect_1:  0.04228 95 % CI  0.0009312 0.1061973

Total Effect:  0.03797 95 % CI  -0.004335  0.101359

Proportion of Total Effect via Mediation_0:  -0.1069 95 % CI  -1.592  0.817

Proportion of Total Effect via Mediation_1:  -0.1701 95 % CI  -1.8595  0.8059


Mediation Effect (Average):  -0.005433 95 % CI  -0.011059 -0.000928

Direct Effect (Average):  0.0434 95 % CI  0.0009659 0.1098405

Proportion of Total Effect via Mediation (Average):  -0.1391 95 % CI
-1.7258  0.8114


Can somebody help me to explain this?


Thanks a lot.

Sincerely,


Weichao
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