After running xtreg on a model with a continuous dependent variable, I want to test the differences between levels of the intervention treatment. What is the difference between running margins VS contrast?

I see the first uses a chi test and the second uses an F test. The only real difference in results is the p-value for the comparison of level 2 vs 1 in the first is .0733, while it is .08 in the second.

Which command should I use? In this case, there is little difference, but could there be a case where the p-value difference between the two is substantial for interpretation?

Code:
.         margins ar.interven123
Contrasts of predictive margins
Model VCE    : Robust
Expression   : Linear prediction, predict()

                    df         chi2     P>chi2
interven123 
(1 vs 0)            1        0.02     0.8963
(2 vs 1)            1        3.21     0.0733
(3 vs 2)            1       12.00     0.0005
Joint               3       17.54     0.0005



Delta-method
                Contrast   Std. Err.     [95% Conf. Interval]
interven123 
(1 vs 0)    -1735.885   13315.37     -27833.52    24361.75
(2 vs 1)        37908   21165.87      -3576.35    79392.35
(3 vs 2)    -21796.77     6293.4      -34131.6   -9461.928


.         contrast ar.interven123, effects

Contrasts of marginal linear predictions
Margins      : asbalanced

                     df          F        P>F
interven123 
(1 vs 0)            1        0.02     0.8969
(2 vs 1)            1        3.21     0.0802
(3 vs 2)            1       12.00     0.0012
Joint               3        5.85     0.0019

Denominator          44
   
              Contrast   Std. Err.      t    P>t     [95% Conf.    Interval]
    
interven123 
(1 vs 0)    -1735.885   13315.37    -0.13   0.897    -28571.24    25099.47
(2 vs 1)        37908   21165.87     1.79   0.080    -4749.015    80565.01
(3 vs 2)    -21796.77     6293.4    -3.46   0.001    -34480.28    -9113.251
    

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