When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples
Under exceptional circumstances, including high rates of protocol non-compliance, per-protocol (PP) analysis can better indicate the real-world benefits of a medical intervention than intention-to-treat (ITT) analysis. Exemplifying this, the first randomized clinical trial (RCT) considered found tha...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-05-01
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| Series: | Journal of Clinical Medicine |
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| Online Access: | https://www.mdpi.com/2077-0383/12/11/3625 |
| _version_ | 1797597357502627840 |
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| author | David E. Scheim Colleen Aldous Barbara Osimani Edmund J. Fordham Wendy E. Hoy |
| author_facet | David E. Scheim Colleen Aldous Barbara Osimani Edmund J. Fordham Wendy E. Hoy |
| author_sort | David E. Scheim |
| collection | DOAJ |
| description | Under exceptional circumstances, including high rates of protocol non-compliance, per-protocol (PP) analysis can better indicate the real-world benefits of a medical intervention than intention-to-treat (ITT) analysis. Exemplifying this, the first randomized clinical trial (RCT) considered found that colonoscopy screenings were marginally beneficial, based upon ITT analysis, with only 42% of the intervention group actually undergoing the procedure. However, the study authors themselves concluded that the medical efficacy of that screening was a 50% reduction in colorectal cancer deaths among that 42% PP group. The second RCT found a ten-fold reduction in mortality for a COVID-19 treatment drug vs. placebo by PP analysis, but only a minor benefit by ITT analysis. The third RCT, conducted as an arm of the same platform trial as the second RCT, tested another COVID-19 treatment drug and reported no significant benefit by ITT analysis. Inconsistencies and irregularities in the reporting of protocol compliance for this study required consideration of PP outcomes for deaths and hospitalizations, yet the study coauthors refused to disclose them, instead directing inquiring scientists to a data repository which never held the study’s data. These three RCTs illustrate conditions under which PP outcomes may differ significantly from ITT outcomes and the need for data transparency when these reported or indicated discrepancies arise. |
| first_indexed | 2024-03-11T03:05:06Z |
| format | Article |
| id | doaj.art-dc65ef0e8fc443ca810fb8c76944a459 |
| institution | Directory Open Access Journal |
| issn | 2077-0383 |
| language | English |
| last_indexed | 2024-03-11T03:05:06Z |
| publishDate | 2023-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Clinical Medicine |
| spelling | doaj.art-dc65ef0e8fc443ca810fb8c76944a4592023-11-18T08:04:12ZengMDPI AGJournal of Clinical Medicine2077-03832023-05-011211362510.3390/jcm12113625When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three ExamplesDavid E. Scheim0Colleen Aldous1Barbara Osimani2Edmund J. Fordham3Wendy E. Hoy4US Public Health Service, Commissioned Corps, Inactive Reserve, Blacksburg, VA 24060, USACollege of Health Sciences, University of KwaZulu-Natal, Durban 4041, South AfricaCenter for Philosophy, Science, and Policy, Faculty of Medicine, Marche Polytechnic University, 60121 Ancona, ItalyEbMCsquared CIC, Bath BA2 4BL, UKCentre of Chronic Disease, Faculty of Medicine, University of Queensland, Brisbane 4072, AustraliaUnder exceptional circumstances, including high rates of protocol non-compliance, per-protocol (PP) analysis can better indicate the real-world benefits of a medical intervention than intention-to-treat (ITT) analysis. Exemplifying this, the first randomized clinical trial (RCT) considered found that colonoscopy screenings were marginally beneficial, based upon ITT analysis, with only 42% of the intervention group actually undergoing the procedure. However, the study authors themselves concluded that the medical efficacy of that screening was a 50% reduction in colorectal cancer deaths among that 42% PP group. The second RCT found a ten-fold reduction in mortality for a COVID-19 treatment drug vs. placebo by PP analysis, but only a minor benefit by ITT analysis. The third RCT, conducted as an arm of the same platform trial as the second RCT, tested another COVID-19 treatment drug and reported no significant benefit by ITT analysis. Inconsistencies and irregularities in the reporting of protocol compliance for this study required consideration of PP outcomes for deaths and hospitalizations, yet the study coauthors refused to disclose them, instead directing inquiring scientists to a data repository which never held the study’s data. These three RCTs illustrate conditions under which PP outcomes may differ significantly from ITT outcomes and the need for data transparency when these reported or indicated discrepancies arise.https://www.mdpi.com/2077-0383/12/11/3625intention-to-treatper-protocolcolonoscopyfluvoxamineivermectinCOVID-19 |
| spellingShingle | David E. Scheim Colleen Aldous Barbara Osimani Edmund J. Fordham Wendy E. Hoy When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples Journal of Clinical Medicine intention-to-treat per-protocol colonoscopy fluvoxamine ivermectin COVID-19 |
| title | When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples |
| title_full | When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples |
| title_fullStr | When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples |
| title_full_unstemmed | When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples |
| title_short | When Characteristics of Clinical Trials Require Per-Protocol as Well as Intention-to-Treat Outcomes to Draw Reliable Conclusions: Three Examples |
| title_sort | when characteristics of clinical trials require per protocol as well as intention to treat outcomes to draw reliable conclusions three examples |
| topic | intention-to-treat per-protocol colonoscopy fluvoxamine ivermectin COVID-19 |
| url | https://www.mdpi.com/2077-0383/12/11/3625 |
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