SPACI score report for 3tat in ASTRAL 1.73:

PDB Entry: 3tat
SPACI score: 0.08
AEROSPACI score: 0.08

Experiment type: XRAY
Resolution: 3.5
R-factor: 0.213
PCK1 PROCHECK Ramachandran: 2
PCK2 PROCHECK Chi-1 angle: 4
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -2.209
WCK2 WHAT_CHECK Ramachandran: -7.711
WCK3 WHAT_CHECK Chi angles: -6.069
WCK4 WHAT_CHECK Backbone: -11.95

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).