SPACI score report for 3n48 in ASTRAL 2.06:

PDB Entry: 3n48
SPACI score: 0.51
AEROSPACI score: 0.51

Experiment type: XRAY
Resolution: 1.9
R-factor: 0.19
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 1
WCK1 WHAT_CHECK Packing: 0.016
WCK2 WHAT_CHECK Ramachandran: 0.968
WCK3 WHAT_CHECK Chi angles: 0.518
WCK4 WHAT_CHECK Backbone: 0.902

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).