Abstract
Although cohort studies which are based on intention-to-treat (ITT) approach offer a simple design with data which are simpler to analyse and results easier to interpret, such studies also intrinsically assume that any time-varying treatment effect that exits can be adequately estimated by a fixed-effect component. However, such an assumption may not reflect real-life drug use. Reflection of real-life clinical practice is a major strength of epidemiologic safety studies. The failure to properly reflect reality may result in effect under-estimation leading to false and irreproducible conclusions due to exposure misclassification. In effect, the use of nested case-control design is a concession that ITT in cohort design may not be adequate. But the nested design also has its own sources of bias, including confounding by indication. We present an overview of the counter-matched version of the nested case-control, case-crossover, case-in-time, case series and case-cohort designs as alternatives in prospective post-authorization safety studies.
Keywords: Cohort study, selection bias, case-control design, counter-matching
Current Drug Safety
Title: How Real is Intention-To-Treat (ITT) Analysis in Non-Interventional Post Authorization Safety Studies? We Can Do Better
Volume: 4 Issue: 2
Author(s): Victor A. Kiri and Gilbert MacKenzie
Affiliation:
Keywords: Cohort study, selection bias, case-control design, counter-matching
Abstract: Although cohort studies which are based on intention-to-treat (ITT) approach offer a simple design with data which are simpler to analyse and results easier to interpret, such studies also intrinsically assume that any time-varying treatment effect that exits can be adequately estimated by a fixed-effect component. However, such an assumption may not reflect real-life drug use. Reflection of real-life clinical practice is a major strength of epidemiologic safety studies. The failure to properly reflect reality may result in effect under-estimation leading to false and irreproducible conclusions due to exposure misclassification. In effect, the use of nested case-control design is a concession that ITT in cohort design may not be adequate. But the nested design also has its own sources of bias, including confounding by indication. We present an overview of the counter-matched version of the nested case-control, case-crossover, case-in-time, case series and case-cohort designs as alternatives in prospective post-authorization safety studies.
Export Options
About this article
Cite this article as:
Kiri A. Victor and MacKenzie Gilbert, How Real is Intention-To-Treat (ITT) Analysis in Non-Interventional Post Authorization Safety Studies? We Can Do Better, Current Drug Safety 2009; 4 (2) . https://dx.doi.org/10.2174/157488609788173008
DOI https://dx.doi.org/10.2174/157488609788173008 |
Print ISSN 1574-8863 |
Publisher Name Bentham Science Publisher |
Online ISSN 2212-3911 |
- Author Guidelines
- Graphical Abstracts
- Fabricating and Stating False Information
- Research Misconduct
- Post Publication Discussions and Corrections
- Publishing Ethics and Rectitude
- Increase Visibility of Your Article
- Archiving Policies
- Peer Review Workflow
- Order Your Article Before Print
- Promote Your Article
- Manuscript Transfer Facility
- Editorial Policies
- Allegations from Whistleblowers
Related Articles
-
Antimicrobial Proteins from Snake Venoms: Direct Bacterial Damage and Activation of Innate Immunity Against Staphylococcus aureus Skin Infection
Current Medicinal Chemistry Classic β-Amyloid Deposits Cluster Around Large Diameter Blood Vessels Rather than Capillaries in Sporadic Alzheimers Disease
Current Neurovascular Research Intrathecal Enzyme Replacement Therapy for Mucopolysaccharidosis I: Translating Success in Animal Models to Patients
Current Pharmaceutical Biotechnology Thalidomide as an Immunotherapeutic Agent: The Effects on Neutrophil- Mediated Inflammation
Current Pharmaceutical Design Enterobacteriaceae that Produce Extended-spectrum β -lactamases and AmpC β -lactamases in the Community: The Tip of the Iceberg?
Current Pharmaceutical Design New Perspectives in the Pharmacological Treatment of Non-Melanoma Skin Cancer
Current Drug Targets The Association of Collagenase with Human Diseases and its Therapeutic Potential in Overcoming them
Current Biotechnology Fluoroquinolones: Blessings Or Curses
Current Drug Targets Advances in the Physiology of GPR55 in the Central Nervous System
Current Neuropharmacology Can Mycobacterial Genomics Generate Novel Targets as Speed-Breakers Against the Race for Drug Resistance
Current Pharmaceutical Design Biologic Therapy in Psoriasis: Safety Profile
Current Drug Safety The Role of Melatonin in Multiple Sclerosis, Huntington's Disease and Cerebral Ischemia
CNS & Neurological Disorders - Drug Targets Immune Checkpoint Inhibitors and Neurotoxicity
Current Neuropharmacology IL-17A and Multiple Sclerosis: Signaling Pathways, Producing Cells and Target Cells in the Central Nervous System
Current Drug Targets Drug Targeting Approaches and Use of Drug Delivery Systems in Management of Cancer
Current Pharmaceutical Design Clinical Significance of Cytokines and Chemokines in Neuropsychiatric Systemic Lupus Erythematosus
Current Rheumatology Reviews Meningococcal Vaccines
Current Pharmaceutical Design Gene Therapy to Improve Pancreatic Islet Transplantation for Type 1 Diabetes Mellitus
Current Diabetes Reviews Antimicrobial Drug Interactions in the Critically Ill Patients
Current Clinical Pharmacology Corticosteroids in Sepsis: Pathophysiological Rationale and the Selection of Patients
Endocrine, Metabolic & Immune Disorders - Drug Targets