Interpolation method in numerical integration

Dear all,

I have a question regarding the integration mechanism in Comsol.

If one integrates an expression with Comsol, for example on a 3D simulation volume, as a derived value in results or using mphint2 in Matlab with Comsol, does Comsol interpolate the integrated expression between the mesh nodes and if yes what method does it use to do that?
(like: linear interpolation/nearest neighbor/natural neighbor/ ...)

Within the reference manual the only information regarding that is uses a "standard numerical integration method (quadrature)", but I don't know what that means regarding the points where it wants to evaluate the expression to perform the numerical integration.

Thanks already in advance for your help.

Best regards,
Hannes