Related Experiment Video
Updated: Feb 14, 2026
Author Spotlight: Implementation of BIVA for Analyzing Disease Risk Factors in Patients with Low Body Cell Mass
Published on: July 14, 2023
Evaluation of a Methodologic Approach to Define an Inception Cohort of Rheumatoid Arthritis Patients Using
Jeffrey R Curtis1, Fenglong Xie1, Lang Chen1
1University of Alabama at Birmingham.
Objective:
Identifying incident rheumatoid arthritis (RA) is desirable in order to create inception cohorts. We evaluated an approach to identify incident RA in health plan claims data.
Methods:
Both Medicare and commercial claims data were linked to Corrona, a US RA registry. We evaluated the accuracy of year of RA onset in the registry (gold standard) versus different claims algorithms, varying International Classification of Diseases, Ninth Revision codes for RA/arthritis, duration of health plan enrollment preceding diagnosis (minimum of 1 versus 2 years), and use of RA medications. Results were reported as positive predictive values (PPVs) of the claims-based algorithm for incident RA.
Results:
Depending on the algorithm tested and whether patients were enrolled in Medicare or the commercial health plan, the PPVs for incident RA ranged from 68-81%. A 2-year clean period free of all RA-related diagnoses and medications was somewhat more optimal although, by comparison, a 1-year clean period yielded similar PPVs and retained approximately 90% more RA patients for analysis.
Conclusion:
Claims-based algorithms can accurately identify incident RA.
Related Concept Videos
01:14Model Approaches for Pharmacokinetic Data: Compartment Models
Two primary types of compartment models are recognized: mammillary and catenary. The more...
01:15Model Approaches for Pharmacokinetic Data: Physiological Models
00:59Model-Independent Approaches for Pharmacokinetic Data: Noncompartmental Analysis
One important characteristic of noncompartmental analyses is that drug exposure increases proportionally with increasing doses. This...
01:06Model Approaches for Pharmacokinetic Data: Distributed Parameter Models
The distributed parameter models are specifically designed to account for variations and differences in some drug classes. This model is particularly useful for assessing regional concentrations of anticancer or...
01:24Defining Psychology
01:14Analysis Methods of Pharmacokinetic Data: Model and Model-Independent Approaches
The model approach uses mathematical models to describe changes in drug concentration over time. Pharmacokinetic models help characterize drug behavior in patients, predict drug concentration in the body fluids, calculate optimum dosage regimens, and evaluate the risk of toxicity. However, ensuring that the model fits the experimental data accurately...