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Research, Methods, Statistics

Regression Models for Ordinal Outcomes

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JAMA

Published Online: August 4, 2022

JAMA Guide to Statistics and Methods

Article Information and Disclosures

Benjamin French, PhD^1,2;

Matthew S. Shotwell, PhD¹

Author Affiliations

¹Department of Biostatistics, Vanderbilt University Medical Center, Nashville, Tennessee
²Statistical Editor, JAMA Pediatrics

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In the December 1, 2020, issue of JAMA, Self et al¹ reported a randomized clinical trial that evaluated whether treatment with hydroxychloroquine improved clinical outcomes of adults hospitalized with COVID-19 compared with placebo. The primary outcome was the patient’s clinical status 14 days after randomization, assessed with an ordinal 7-category scale ranging from worst (“death”) to the best (“discharged from the hospital and able to perform normal activities”). The term “ordinal” is applied to an outcome measure for which its mutually exclusive categories can be ordered by their clinical preference. The primary outcome was analyzed with a multivariable ordinal logistic regression model, which is a regression model for an ordinal dependent variable. The authors found that there was not a statistically significant difference between the hydroxychloroquine and placebo groups in clinical status 14 days after randomization.

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Article Information

Corresponding Author: Benjamin French, PhD, Department of Biostatistics, Vanderbilt University Medical Center, 2525 West End Ave, Ste 1100, Nashville, TN 37203 (b.french@vumc.org).

Published Online: August 4, 2022. doi:10.1001/jama.2022.12104

Conflict of Interest Disclosures: None reported.

References

Self WH , Semler MW , Leither LM , et al; National Heart, Lung, and Blood Institute PETAL Clinical Trials Network. Effect of hydroxychloroquine on clinical status at 14 days in hospitalized patients with COVID-19: a randomized clinical trial. JAMA. 2020;324(21):2165-2176. doi:10.1001/jama.2020.22240 PubMed Google Scholar Crossref

Stevens SS . On the theory of scales of measurement. Science. 1946;103(2684):677-680. doi:10.1126/science.103.2684.677 PubMed Google Scholar Crossref

Roozenbeek B , Lingsma HF , Perel P , et al; IMPACT (International Mission on Prognosis and Clinical Trial Design in Traumatic Brain Injury) Study Group; CRASH (Corticosteroid Randomisation After Significant Head Injury) Trial Collaborators. The added value of ordinal analysis in clinical trials: an example in traumatic brain injury. Crit Care. 2011;15(3):R127. doi:10.1186/cc10240 PubMed Google Scholar Crossref

Liu Q , Shepherd BE , Li C , Harrell FE Jr . Modeling continuous response variables using ordinal regression. Stat Med. 2017;36(27):4316-4335. doi:10.1002/sim.7433 PubMed Google Scholar Crossref

McCullagh P . Regression models for ordinal data. J R Stat Soc Series B Stat Methodol. 1980;42(2):109-142.Google Scholar

Harrel F . Assessing the proportional odds assumption and its impact. Statistical Thinking blog. March 9, 2022. Accessed April 29, 2022. https://www.fharrell.com/post/impactpo

Schildcrout JS , Harrell FE Jr , Heagerty PJ , et al. Model-assisted analyses of longitudinal, ordinal outcomes with absorbing states. Stat Med. 2022;41(14):2497-2512. doi:10.1002/sim.9366 PubMed Google Scholar Crossref

Norton EC , Dowd BE , Maciejewski ML . Marginal effects—quantifying the effect of changes in risk factors in logistic regression models. JAMA. 2019;321(13):1304-1305. doi:10.1001/jama.2019.1954 PubMed Google Scholar Crossref

Saver JL , Lewis RJ . Number needed to treat: conveying the likelihood of a therapeutic effect. JAMA. 2019;321(8):798-799. doi:10.1001/jama.2018.21971 PubMed Google Scholar Crossref

Detry MA , Ma Y . Analyzing repeated measurements using mixed models. JAMA. 2016;315(4):407-408. doi:10.1001/jama.2015.19394 PubMed Google Scholar Crossref

AMA CME Accreditation Information

Credit Designation Statement: The American Medical Association designates this Journal-based CME activity activity for a maximum of 1.00  AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Successful completion of this CME activity, which includes participation in the evaluation component, enables the participant to earn up to:

1.00 Medical Knowledge MOC points in the American Board of Internal Medicine's (ABIM) Maintenance of Certification (MOC) program;;
1.00 Self-Assessment points in the American Board of Otolaryngology – Head and Neck Surgery’s (ABOHNS) Continuing Certification program;
1.00 MOC points in the American Board of Pediatrics’ (ABP) Maintenance of Certification (MOC) program;
1.00 Lifelong Learning points in the American Board of Pathology’s (ABPath) Continuing Certification program; and
1.00 CME points in the American Board of Surgery’s (ABS) Continuing Certification program

It is the CME activity provider's responsibility to submit participant completion information to ACCME for the purpose of granting MOC credit.