SPACI score report for 1n90 in ASTRAL 1.73:

PDB Entry: 1n90
SPACI score: 0.26
AEROSPACI score: 0.26

Experiment type: XRAY
Resolution: 2.9
R-factor: 0.204
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -0.096
WCK2 WHAT_CHECK Ramachandran: -2.168
WCK3 WHAT_CHECK Chi angles: -0.873
WCK4 WHAT_CHECK Backbone: -4.705

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).