Table 1. A list of PDBx/mmCIF data items that are made consistent in all entries in the PDB archive before the data are loaded into the PDBe database. The second column summarises the changes made to each data item to make it consistent.

_struct_ref_seq_dif.details	Describes the observed differences between a residue in the PDB and corresponding residue in reference database (e.g. UniProt for protein molecules)
_exptl.method	Describes the experimental methods used to determine the 3D structure.
_diffrn_source.source	The radiation source used to carry out the diffraction experiment, e.g. ‘Rotating anode’
_citation.journal_abbrev	The abbreviated name of the cited journal
_diffrn_radiation.pdbx_diffrn_protocol	Diffraction protocol used, e.g. ‘Single wavelength’, ‘MAD’ etc.
_diffrn_detector.detector	The type of detector used in the diffraction experiment
_computing.structure_refinement	Software used for refinement of the structure
_symmetry.space_group_name_H-M	Space group symmetry