title: Evaluation of the methodological quality of studies of the performance of diagnostic tests for bovine tuberculosis using QUADAS.
abstract: There has been little assessment of the methodological quality of studies measuring the performance (sensitivity and/or specificity) of diagnostic tests for animal diseases. In a systematic review, 190 studies of tests for bovine tuberculosis (bTB) in cattle (published 1934-2009) were assessed by at least one of 18 reviewers using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) checklist adapted for animal disease tests. VETQUADAS (VQ) included items measuring clarity in reporting (n = 3), internal validity (n = 9) and external validity (n = 2). A similar pattern for compliance was observed in studies of different diagnostic test types. Compliance significantly improved with year of publication for all items measuring clarity in reporting and external validity but only improved in four of the nine items measuring internal validity (p < 0.05). 107 references, of which 83 had performance data eligible for inclusion in a meta-analysis were reviewed by two reviewers. In these references, agreement between reviewers' responses was 71% for compliance, 32% for unsure and 29% for non-compliance. Mean compliance with reporting items was 2, 5.2 for internal validity and 1.5 for external validity. The index test result was described in sufficient detail in 80.1% of studies and was interpreted without knowledge of the reference standard test result in only 33.1%. Loss to follow-up was adequately explained in only 31.1% of studies. The prevalence of deficiencies observed may be due to inadequate reporting but may also reflect lack of attention to methodological issues that could bias the results of diagnostic test performance estimates. QUADAS was a useful tool for assessing and comparing the quality of studies measuring the performance of diagnostic tests but might be improved further by including explicit assessment of population sampling strategy.
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom. Electronic address: sara.downs@apha.gsi.gov.uk.
authors.forename: Sara H
authors.initials: SH
authors.lastname: Downs
authors.affiliation: Centre for Veterinary Epidemiology and Risk Analysis, UCD School of Veterinary Medicine, Belfield, Dublin 4, Ireland.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: More
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Anthony V
authors.initials: AV
authors.lastname: Goodchild
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom; Microbiology, Dstl, Porton Down, SP4 0JQ, United Kingdom.
authors.forename: Adam O
authors.initials: AO
authors.lastname: Whelan
authors.affiliation: Veterinary Service, Department of Agriculture and Rural Development, Belfast BT4 3SB, United Kingdom; Faculty of Veterinary Science, University of Pretoria, South Africa.
authors.forename: Darrell A
authors.initials: DA
authors.lastname: Abernethy
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Broughan
authors.affiliation: AusVet Animal Health Services Pty. Ltd., PO Box 3180, South Brisbane, Qld 4101, Australia.
authors.forename: Angus
authors.initials: A
authors.lastname: Cameron
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom; Department of Veterinary Epidemiology, School of Veterinary Medicine, University of Surrey, GU2 7AL, United Kingdom.
authors.forename: Alasdair J
authors.initials: AJ
authors.lastname: Cook
authors.affiliation: Advice Services, APHA, and Bovine Tuberculosis Programme, Department for Environment, Food and Rural Affairs, London SW1P 3JR, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Ricardo de la Rua-Domenech
authors.affiliation: Federal Institute for Risk Assessment (BfR), D-14195 Berlin, Germany and University of Veterinary Medicine, Hannover, Foundation, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Greiner
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Jane
authors.initials: J
authors.lastname: Gunn
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Javier
authors.initials: J
authors.lastname: Nuñez-Garcia
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Shelley
authors.initials: S
authors.lastname: Rhodes
authors.affiliation: Office of the Chief Veterinary Officer, Welsh Assembly Government, Cardiff CF10 3NQ, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Rolfe
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: Sharp
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Paul
authors.initials: P
authors.lastname: Upton
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom; National Milk Laboratories, Wiltshire SN15 1BN, United Kingdom.
authors.forename: Eamon
authors.initials: E
authors.lastname: Watson
authors.affiliation: Veterinary Sciences Division, Agri-Food & Biosciences Institute (AFBI), Belfast BT4 3SD, United Kingdom; CSO SISAF Ltd., Northern Ireland Science Park, Unit 15A The Innovation Centre, Belfast BT3 9DT, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: Welsh
authors.affiliation: The Roslin Institute, Roslin Biocentre, Roslin, Midlothian EH25 9PS, United Kingdom.
authors.forename: John A
authors.initials: JA
authors.lastname: Woolliams
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Clifton-Hadley
authors.affiliation: Animal and Plant Health Agency (APHA), Weybridge, Surrey KT15 3NB, United Kingdom.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Parry
mesh_terms: D000818:Animals; D015982:Bias; D002417:Cattle; D003955:Diagnostic Tests, Routine / Q000379:methods / Q000592:standards / Q000662:veterinary*; D012680:Sensitivity and Specificity; D014380:Tuberculosis, Bovine / Q000175:diagnosis*
keywords: Bovine tuberculosis; Diagnostic tests; Evaluation; External validity; Internal validity; Quality