Table 4. Fields, data types, discrepancy rates and interpretational issues in quality check tests of Australian Bird Data Version 1 (Data Citation 1).

Field category	Fields [description]	Nature of data	Level of interpretation	Test taxa	n fields checked	n species checked *	n cells checked	% error in database	% interpretational discrepancies	Source of interpretational discrepancies
Taxonomy & nomenclature	Species, Subspecies, Ultrataxon	binary	None	all	3	100	296	0	0
Australian population status	Population description	16 categories	Moderate	species	1	100	100	0	0
Australian population status	Core, Non-breeding population, Extinct, Introduced, Vagrant, Supplementary	binary	Slight	species	6	95	570	0	0
Conservation status	Global IUCN status 2014	9 categories	None	species	1	99	99	0	0
Distribution	[Occurrence on] Continental islands and Offshore islands only	binary/tertiary	Slight	all	3	95	285	0	0
Habitat	[breeding habitats]	binary	Great	species	17	87	1479	1.1	2.1	misalignment of habitat categories between database and sources, and failure of source to discriminate between breeding and other habitat
Breeding	Nest aggregation: Solitary, Colonial, Parasitic	binary	Moderate	species	3	78	234	0.6	1.9	borderline cases between solitary and dispersed (loose) colonies

*this was often less than the 100 taxa randomly selected because the test extractor proved unable to identify suitable data from the key source.