title: Comparison of Characteristics and Outcomes of Trial Participants and Nonparticipants: Example of Blood and Marrow Transplant Clinical Trials Network 0201 Trial.
abstract: Controversy surrounds the question of whether clinical trial participants have better outcomes than comparable patients who are not treated on a trial. We explored this question using a recent large, randomized, multicenter study comparing peripheral blood (PB) with bone marrow transplantation from unrelated donors, conducted by the Blood and Marrow Transplant Clinical Trials Network (BMT CTN). We compared characteristics and outcomes of study participants (n = 494) and nonparticipants (n = 1384) who appeared eligible and received similar treatment without enrolling on the BMT CTN trial at participating centers during the study time period. Data were obtained from the Center for International Blood and Marrow Transplant Research. Outcomes were compared between the 2 groups using Cox proportional hazards regression models. No significant differences in age, sex, disease distribution, race/ethnicity, HLA matching, comorbidities, and interval from diagnosis to hematopoietic cell transplantation were seen between the participants and nonparticipants. Nonparticipants were more likely to have lower performance status, lower risk disease, and older donors, and to receive myeloablative conditioning and antithymocyte globulin. Nonparticipants were also more likely to receive PB grafts, the intervention tested in the trial (66% versus 50%, P < .001). Overall survival, transplantation-related mortality, and incidences of acute or chronic graft-versus-host disease were comparable between the 2 groups though relapse was higher (hazard ratio, 1.22; 95% confidence interval, 1.02 to 1.46; P = .028) in nonparticipants. Despite differences in certain baseline characteristics, survival was comparable between study participants and nonparticipants. The results of the BMT CTN trial appear generalizable to the population of trial-eligible patients.
authors.affiliation: Department of Hematology/Oncology, Mayo Clinic, Phoenix, Arizona. Electronic address: khera.nandita@mayo.edu.
authors.forename: Nandita
authors.initials: N
authors.lastname: Khera
authors.affiliation: Blood and Marrow Transplant Program, Cleveland Clinic, Taussig Cancer Institute, Cleveland, Ohio.
authors.forename: Navneet S
authors.initials: NS
authors.lastname: Majhail
authors.affiliation: Center for International Blood and Marrow Transplant Research, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin; Division of Biostatistics, Institute of Health and Society, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Ruta
authors.initials: R
authors.lastname: Brazauskas
authors.affiliation: Center for International Blood and Marrow Transplant Research, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Center for International Blood and Marrow Transplant Research, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Naya
authors.initials: N
authors.lastname: He
authors.affiliation: Department of Oncology, King Faisal Specialist Hospital Center and Research, Riyadh, Saudi Arabia.
authors.forename: Mahmoud D
authors.initials: MD
authors.lastname: Aljurf
authors.affiliation: Section of Hematology Oncology, Banner MD Anderson Cancer Center, Gilbert, Arizona.
authors.forename: Görgün
authors.initials: G
authors.lastname: Akpek
authors.affiliation: Japanese Data Center for Hematopoietic Cell Transplantation, Nagoya, Japan; Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Atsuta
authors.affiliation: School of Psychology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Sara
authors.initials: S
authors.lastname: Beattie
authors.affiliation: Ottawa Hospital Blood and Marrow Transplant Program and the Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Bredeson
authors.affiliation: Health Services Research, National Marrow Donor Program/Be The Match, Minneapolis, Minnesota.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Burns
authors.affiliation: Bone Marrow Transplantation, Pediatric Hematology/Oncology, The Children's Mercy Hospitals and Clinics, Kansas City, Missouri.
authors.forename: Jignesh D
authors.initials: JD
authors.lastname: Dalal
authors.affiliation: South Texas Veterans Health Care System and University of Texas Health Science Center San Antonio, San Antonio, Texas.
authors.forename: César O
authors.initials: CO
authors.lastname: Freytes
authors.affiliation: Blood and Marrow Transplant Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.
authors.forename: Vikas
authors.initials: V
authors.lastname: Gupta
authors.affiliation: Division of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Inamoto
authors.affiliation: Seidman Cancer Center, University Hospitals Case Medical Center, Cleveland, Ohio.
authors.forename: Hillard M
authors.initials: HM
authors.lastname: Lazarus
authors.affiliation: Hematology and Bone Marrow Transplant, Sarah Cannon, Nashville, Tennessee.
authors.forename: Charles F
authors.initials: CF
authors.lastname: LeMaistre
authors.affiliation: Department of Hematology-Oncology, Mount Sinai Hospital, New York, New York.
authors.forename: Amir
authors.initials: A
authors.lastname: Steinberg
authors.affiliation: Department of Hematology, CancerCare Manitoba/University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Szwajcer
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, Florida.
authors.forename: John R
authors.initials: JR
authors.lastname: Wingard
authors.affiliation: Department of Internal Medicine, Stony Brook University Medical Center, Stony Brook, New York.
authors.forename: Baldeep
authors.initials: B
authors.lastname: Wirk
authors.affiliation: Division of Hematology/Oncology, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: William A
authors.initials: WA
authors.lastname: Wood
authors.affiliation: Department of Medical Ethics and Health Policy, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.
authors.forename: Steven
authors.initials: S
authors.lastname: Joffe
authors.affiliation: Department of Medicine, Roswell Park Cancer Institute, Buffalo, New York.
authors.forename: Theresa E
authors.initials: TE
authors.lastname: Hahn
authors.affiliation: Department of Internal Medicine, Nebraska Medical Center, Omaha, Nebraska.
authors.forename: Fausto R
authors.initials: FR
authors.lastname: Loberiza
authors.affiliation: Bone Marrow Transplant Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida.
authors.forename: Claudio
authors.initials: C
authors.lastname: Anasetti
authors.affiliation: Center for International Blood and Marrow Transplant Research, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Mary M
authors.initials: MM
authors.lastname: Horowitz
authors.affiliation: Clinical Transplant Research, Fred Hutchinson Cancer Research Center, Seattle, Washington.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000961:Antilymphocyte Serum / Q000627:therapeutic use; D016026:Bone Marrow Transplantation / Q000401:mortality / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006086:Graft vs Host Disease / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D007231:Infant, Newborn; D007297:Inpatients / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D019653:Myeloablative Agonists / Q000627:therapeutic use; D018579:Patient Selection; D036102:Peripheral Blood Stem Cell Transplantation / Q000401:mortality / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012008:Recurrence; D012042:Registries; D012074:Remission Induction; D035842:Research Subjects / Q000706:statistics & numerical data; D016019:Survival Analysis; D013601:T-Lymphocytes / Q000276:immunology; D019172:Transplantation Conditioning / Q000379:methods; D016896:Treatment Outcome; D061349:Unrelated Donors; D055815:Young Adult
chemical_list: D000961:Antilymphocyte Serum; D007166:Immunosuppressive Agents; D019653:Myeloablative Agonists
keywords: Hematopoietic cell transplantation; Trial participation