SPACI score report for 3tnn in ASTRAL 2.07:

PDB Entry: 3tnn
SPACI score: 0.44
AEROSPACI score: 0.44

Experiment type: XRAY
Resolution: 1.95
R-factor: 0.2
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -0.019
WCK2 WHAT_CHECK Ramachandran: -1.72
WCK3 WHAT_CHECK Chi angles: -2.306
WCK4 WHAT_CHECK Backbone: 2.664

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).