Error in if(!INT & isGam.y) { : the condition has length > 1

[sebsilas]

I recently updated R and my packages and the below code, which was previously working, is no longer working:

fit.dv <- lme4::lmer(opti3 ~ no_recalled_notes + N + condition + log(attempt) + log(attempt):N + (1|unique_melody_name), data = na.omit(main2))

fit.mediator <- lme4::lmer(no_recalled_notes ~ N + condition + log(attempt) + log(attempt):N + (1|unique_melody_name), data = na.omit(main2))

results <- mediation::mediate(fit.mediator, fit.dv, treat = c('N', 'condition'), mediator = 'no_recalled_notes')

The error is:

Error in if(!INT & isGam.y) { : the condition has length > 1

[evagrosfeld]

Good afternoon, I have a similar problem. Have you already resolved the issue?

[sebsilas]

Hi @evagrosfeld. Yes, I think it's because you can only have one treat variable (I just noticed this in the documentation). I moved one of my treat variables (condition in my example above) to the covariates argument, and it works now.

Were you trying to use two or more variables for treat?

[evagrosfeld]

Indeed, I was. Thank you, inserting one of the treat variables as covariates variable solves the issue!