# Is it OK to use lag=1 for Granger causality test?

I have a question related to Granger Causality testing.

Is it okay to use a lag-length of lag=1 in my Granger-test? The optimum lag length selection in my R VARselect(data,lag=maxlag,type=trend) model says that lag=1 shows the best and most stable information criteria values according to AIC, BIC and FPE.

I have a 30-year set of quarterly data and I'm using a maxlag of 4.

If your data is stationary, then yes, based on the information you provided it seems OK to use $\text{lag}=1$.