title: Systematic survey of randomized trials evaluating the impact of alternative diagnostic strategies on patient-important outcomes.
abstract: OBJECTIVE
  To provide a perspective on the current practice of randomized clinical trials (RCTs) of diagnostic strategies focusing on patient-important outcomes.
  
  
  METHODS
  We conducted a comprehensive search of MEDLINE and included RCTs published in full-text reports that evaluated alternative diagnostic strategies.
  
  
  RESULTS
  Of 56,912 unique citations, we sampled 7,500 and included 103 eligible RCTs, therefore suggesting that MEDLINE includes approximately 781 diagnostic RCTs. The 103 eligible trials reported on: mortality (n = 41; 39.8%); morbidities (n = 63; 61.2%); symptoms/quality of life/functional status (n = 14; 13.6%); and on composite end points (n = 10; 9.7%). Of the studies that reported statistically significant results (n = 12; 11.6%), we judged 7 (58.3%) as at low risk of bias with respect to missing outcome data and 4 (33.3%) as at low risk of bias regarding blinding. Of the 41 RCTs that reported on mortality, only one (2.4%) reported statistically significant results. Of 63 RCTs addressing morbidity outcomes, 11 (17.5%) reported statistically significant results, all of which reported relative effects of greater than 20%.
  
  
  CONCLUSIONS
  RCTs of diagnostic tests are not uncommon, and sometimes suggest benefits on patient-important outcomes but often suffer from limitations in sample size and conduct.
authors.affiliation: Department of Anaesthesiology, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil; Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, Unesp-Univ Estadual Paulista, Av. Eng. Francisco José Longo, 777 - Jardim Sao Dimas, São José dos Campos 12245-000, Brazil; McMaster Institute of Urology, McMaster University, St. Josephs Healthcare, 50 Charlton Ave E, Room G344, Hamilton, Ontario L8N 4A6, Canada. Electronic address: eldib@ict.unesp.br.
authors.forename: Regina
authors.initials: R
authors.lastname: El Dib
authors.affiliation: Department of Urology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 4, Helsinki 00029, Finland.
authors.forename: Kari A O
authors.initials: KAO
authors.lastname: Tikkinen
authors.affiliation: Department of Internal Medicine, American University of Beirut Medical Center, P.O. Box 11-0236, Riad-El-Solh, Beirut 1107 2020, Lebanon; Department of Health Research Methods, Evidence, and Impact (HEI), 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Elie A
authors.initials: EA
authors.lastname: Akl
authors.affiliation: Department of Pharmacy, Tanta Chest Hospital, El Bahr St., Tanta, Gharbia 31527, Egypt.
authors.forename: Huda A
authors.initials: HA
authors.lastname: Gomaa
authors.affiliation: Clinical Epidemiology and Biostatistics, Faculty of Health Sciences, HSC-3V43D 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada; Department of Medicine, University of Missouri-Kansas City School of Medicine, M4-303, 2411 Holmes St., Kansas City, MO 64108-2792, USA.
authors.forename: Reem A
authors.initials: RA
authors.lastname: Mustafa
authors.affiliation: School of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
authors.forename: Arnav
authors.initials: A
authors.lastname: Agarwal
authors.affiliation: Department of Emergency Medicine, Washington University School of Medicine in St. Louis, Campus Box 8072, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Carpenter
authors.affiliation: Department of Health Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: Eliane C
authors.initials: EC
authors.lastname: Jorge
authors.affiliation: Department of Tropical Diseases and Imaging Diagnosis, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: Ricardo A M B
authors.initials: RAMB
authors.lastname: Almeida
authors.affiliation: Department of Anaesthesiology, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: do Nascimento Junior
authors.affiliation: Department of Anaesthesiology, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: Joao Vitor P
authors.initials: JVP
authors.lastname: Doles
authors.affiliation: School of Medicine, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan.
authors.forename: Ahmad A
authors.initials: AA
authors.lastname: Mustafa
authors.affiliation: Research Center for Modeling in Health, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Behnam
authors.initials: B
authors.lastname: Sadeghirad
authors.affiliation: Pharmaceutical Science Graduate Course, University of Sorocaba, Rodovia Raposo Tavares, Km 92, 5, Sorocaba, Sao Paulo 18023-000, Brazil.
authors.forename: Luciane C
authors.initials: LC
authors.lastname: Lopes
authors.affiliation: Pharmaceutical Science Graduate Course, University of Sorocaba, Rodovia Raposo Tavares, Km 92, 5, Sorocaba, Sao Paulo 18023-000, Brazil.
authors.forename: Cristiane C
authors.initials: CC
authors.lastname: Bergamaschi
authors.affiliation: Research Institute, Hospital do Coração (HCor), Abílio Soares Street 250, 12th Floor, São Paulo 04005-000, Brazil.
authors.forename: Erica A
authors.initials: EA
authors.lastname: Suzumura
authors.affiliation: Department of Anaesthesiology, Botucatu Medical School, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: Marília M A
authors.initials: MMA
authors.lastname: Cardoso
authors.affiliation: Biostatistics Department, Biosciences Institute, Unesp-Univ Estadual Paulista, Distrito de Rubião Júnior, s/n Univ Estadual Paulista, São Paulo 18618-970, Brazil.
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Corrente
authors.affiliation: Family Medicine and CCFP [EM] Programmes, Northern Ontario School of Medicine, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada.
authors.forename: Samuel B
authors.initials: SB
authors.lastname: Stone
authors.affiliation: Clinical Epidemiology and Biostatistics, Faculty of Health Sciences, HSC-3V43D 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada; Emergency Department, Health Sciences North, 41 Ramsey Lake Rd, Sudbury, Ontario P3E 5J1, Canada.
authors.forename: Holger J
authors.initials: HJ
authors.lastname: Schunemann
authors.affiliation: Clinical Epidemiology and Biostatistics, Faculty of Health Sciences, HSC-3V43D 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada; Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Gordon H
authors.initials: GH
authors.lastname: Guyatt
mesh_terms: D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data*; D006801:Humans; D016239:MEDLINE; D063868:Patient Outcome Assessment; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*
keywords: Accuracy; Alternative diagnostic strategies; Clinical trials; Diagnostic techniques and procedures; Evidence-based medicine; Patient outcome