title: The quality of reporting methods and results of cost-effectiveness analyses in Spain: a methodological systematic review.
abstract: BACKGROUND
  Cost-effectiveness analysis has been recognized as an important tool to determine the efficiency of healthcare interventions and services. There is a need for evaluating the reporting of methods and results of cost-effectiveness analyses and establishing their validity. We describe and examine reporting characteristics of methods and results of cost-effectiveness analyses conducted in Spain during more than two decades.
  
  
  METHODS
  A methodological systematic review was conducted with the information obtained through an updated literature review in PubMed and complementary databases (e.g. Scopus, ISI Web of Science, National Health Service Economic Evaluation Database (NHS EED) and Health Technology Assessment (HTA) databases from Centre for Reviews and Dissemination (CRD), Índice Médico Español (IME) Índice Bibliográfico Español en Ciencias de la Salud (IBECS)). We identified cost-effectiveness analyses conducted in Spain that used quality-adjusted life years (QALYs) as outcome measures (period 1989-December 2014). Two reviewers independently extracted the data from each paper. The data were analysed descriptively.
  
  
  RESULTS
  In total, 223 studies were included. Very few studies (10; 4.5 %) reported working from a protocol. Most studies (200; 89.7 %) were simulation models and included a median of 1000 patients. Only 105 (47.1 %) studies presented an adequate description of the characteristics of the target population. Most study interventions were categorized as therapeutic (189; 84.8 %) and nearly half (111; 49.8 %) considered an active alternative as the comparator. Effectiveness of data was derived from a single study in 87 (39.0 %) reports, and only few (40; 17.9 %) used evidence synthesis-based estimates. Few studies (42; 18.8 %) reported a full description of methods for QALY calculation. The majority of the studies (147; 65.9 %) reported that the study intervention produced "more costs and more QALYs" than the comparator. Most studies (200; 89.7 %) reported favourable conclusions. Main funding source was the private for-profit sector (135; 60.5 %). Conflicts of interest were not disclosed in 88 (39.5 %) studies.
  
  
  CONCLUSIONS
  This methodological review reflects that reporting of several important aspects of methods and results are frequently missing in published cost-effectiveness analyses. Without full and transparent reporting of how studies were designed and conducted, it is difficult to assess the validity of study findings and conclusions.
authors.affiliation: Fundación Instituto de Investigación en Servicios de Salud, Valencia, Spain. ferran_catala@hotmail.com.|Department of Medicine, University of Valencia/INCLIVA Health Research Institute and CIBERSAM, Valencia, Spain. ferran_catala@hotmail.com.|Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), Ottawa, ON, Canada. ferran_catala@hotmail.com.
authors.forename: Ferrán
authors.initials: F
authors.lastname: Catalá-López
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I + CS), Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Zaragoza, Spain. ridao_man@gva.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ridao
authors.affiliation: Department of History of Science and Documentation, University of Valencia, Valencia, Spain. adolfo.alonso@uv.es.
authors.forename: Adolfo
authors.initials: A
authors.lastname: Alonso-Arroyo
authors.affiliation: Fundación Instituto de Investigación en Servicios de Salud, Valencia, Spain. annagarciaaltes@gmail.com.|CIBERESP, Institut d'Investigació Biomèdica (IIB) Sant Pau, Barcelona, Spain. annagarciaaltes@gmail.com.
authors.forename: Anna
authors.initials: A
authors.lastname: García-Altés
authors.affiliation: Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), Ottawa, ON, Canada. cgcameron@gmail.com.|Evidence Synthesis Group, Cornerstone Research Group, Burlington, ON, Canada. cgcameron@gmail.com.
authors.forename: Chris
authors.initials: C
authors.lastname: Cameron
authors.affiliation: Division of Pharmacoepidemiology and Pharmacovigilance, Spanish Medicines and Healthcare Products Agency (AEMPS), Madrid, Spain. dgonzalez@aemps.es.
authors.forename: Diana
authors.initials: D
authors.lastname: González-Bermejo
authors.affiliation: Ingenio-Spanish National Research Council (CSIC) and UISYS-University of Valencia, Valencia, Spain. rafael.aleixandre@uv.e.
authors.forename: Rafael
authors.initials: R
authors.lastname: Aleixandre-Benavent
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I + CS), Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Zaragoza, Spain. ebernal.iacs@aragon.es.
authors.forename: Enrique
authors.initials: E
authors.lastname: Bernal-Delgado
authors.affiliation: FISABIO-Salud Pública, Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Valencia, Spain. peiro_bor@gva.es.
authors.forename: Salvador
authors.initials: S
authors.lastname: Peiró
authors.affiliation: Department of Medicine, University of Valencia/INCLIVA Health Research Institute and CIBERSAM, Valencia, Spain. rafael.tabares@uv.es.
authors.forename: Rafael
authors.initials: R
authors.lastname: Tabarés-Seisdedos
authors.affiliation: Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), Ottawa, ON, Canada. bhutton@ohri.ca.|School of Epidemiology, Public Health and Preventive Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada. bhutton@ohri.ca.
authors.forename: Brian
authors.initials: B
authors.lastname: Hutton
mesh_terms: D003362:Cost-Benefit Analysis / Q000191:economics*; D003695:Delivery of Health Care / Q000191:economics*; D006801:Humans; D012107:Research Design; D013030:Spain
references.citation: BMJ. 2010;340:c723
references.pmid: 20332510
references.citation: Rev Esp Cardiol. 2006 Dec;59(12):1244-51
references.pmid: 17194419
references.citation: Health Econ. 2001 Dec;10(8):715-29
references.pmid: 11747053
references.citation: Value Health. 2011 Jun;14(4):458-64
references.pmid: 21669370
references.citation: Rev Esp Salud Publica. 2010 Jul-Aug;84(4):353-69
references.pmid: 21141264
references.citation: Med Care. 1993 Jul;31(7 Suppl):JS1-11, JS18-149
references.pmid: 8326780
references.citation: Ann Intern Med. 2013 Feb 5;158(3):200-7
references.pmid: 23295957
references.citation: Eur J Health Econ. 2014 Nov;15(8):829-40
references.pmid: 23974963
references.citation: Value Health. 2005 Sep-Oct;8(5):521-33
references.pmid: 16176491
references.citation: Ann Intern Med. 1995 Jul 1;123(1):61-70
references.pmid: 7762918
references.citation: BMJ. 2010;340:c869
references.pmid: 20332511
references.citation: Ann Intern Med. 2000 Jun 20;132(12):964-72
references.pmid: 10858180
references.citation: BMJ. 2014;349:g6501
references.pmid: 25416499
references.citation: Cochrane Database Syst Rev. 2009;(1):MR000006
references.pmid: 19160345
references.citation: Lancet. 2005 Mar 26-Apr 1;365(9465):1159-62
references.pmid: 15794971
references.citation: JAMA. 2000 Oct 18;284(15):1922-4
references.pmid: 11035882
references.citation: Med Decis Making. 2005 Jul-Aug;25(4):424-8
references.pmid: 16061894
references.citation: PLoS Med. 2007 Mar 27;4(3):e78
references.pmid: 17388659
references.citation: JAMA. 2000 Apr 26;283(16):2158-60
references.pmid: 10791510
references.citation: BMC Med. 2013;11:80
references.pmid: 23531108
references.citation: Lancet. 2014 Jan 11;383(9912):166-75
references.pmid: 24411645
references.citation: PLoS One. 2012;7(5):e38012
references.pmid: 22666435
references.citation: Lancet. 2005 Jan 1-7;365(9453):82-93
references.pmid: 15639683
references.citation: PLoS Med. 2007 Oct 16;4(10):e296
references.pmid: 17941714
references.citation: Eur J Health Econ. 2012 Dec;13(6):723-40
references.pmid: 21660565
references.citation: Value Health. 2010 Mar-Apr;13(2):328-34
references.pmid: 19804434
references.citation: BMJ. 2010;340:c365
references.pmid: 20156912
references.citation: PLoS Med. 2014 Jun;11(6):e1001666
references.pmid: 24959719
references.citation: Eur J Health Econ. 2010 Oct;11(5):513-20
references.pmid: 20405159
references.citation: Syst Rev. 2015;4:1
references.pmid: 25554246
references.citation: Ann Intern Med. 2009 Aug 18;151(4):264-9, W64
references.pmid: 19622511
references.citation: PLoS One. 2013;8(12):e83138
references.pmid: 24386151
references.citation: Syst Rev. 2012;1:60
references.pmid: 23194585
references.citation: PLoS One. 2014;9(3):e92508
references.pmid: 24671099
references.citation: JAMA. 2002 Jun 5;287(21):2809-12
references.pmid: 12038919
references.citation: Health Econ. 1995 Mar-Apr;4(2):85-94
references.pmid: 7613600
references.citation: JAMA. 1996 Oct 23-30;276(16):1339-41
references.pmid: 8861994
references.citation: Med Care. 1998 May;36(5 Suppl):MS1-9, MS18-147
references.pmid: 9599597
references.citation: Pharmacoeconomics. 2009;27(10):861-72
references.pmid: 19803540
references.citation: BMJ. 2006 Mar 25;332(7543):699-703
references.pmid: 16495332
references.citation: Value Health. 2005 Jan-Feb;8(1):3-9
references.pmid: 15841889
references.citation: Pharmacoeconomics. 1995 Sep;8(3):245-52
references.pmid: 10155620
references.citation: Pharmacoeconomics. 1998 Jul;14(1):1-9
references.pmid: 10182189
references.citation: Lancet. 2009 Jul 4;374(9683):86-9
references.pmid: 19525005
references.citation: Ann Intern Med. 2010 Jun 1;152(11):726-32
references.pmid: 20335313
references.citation: Value Health. 2003 Jan-Feb;6(1):9-17
references.pmid: 12535234
references.citation: BMJ. 1996 Aug 3;313(7052):275-83
references.pmid: 8704542