Evidence Hub

Coenrollment of critically ill patients in PROSPECT: characteristics and association with treatment efficacy and safety

A. Thabane, D. Heels-Ansdell, N. Zytaruk, Jennie Johnstone, F. Lauzier, Y. Arabi, J. Muscedere, F. Clarke et al.

Trials, 2025

2,650 participants

Abstract

Coenrollment is the enrollment of one participant into more than one study. While coenrollment can enhance research efficiency, it theoretically may result in treatment interactions that distort effect estimates. This study aimed to explore the sensitivity of safety and efficacy outcomes to coenrollment in an international, blinded randomized controlled trial evaluating probiotic use in critically ill patients (PROSPECT: Probiotics: Prevention of Severe Pneumonia and Endotracheal Colonization Trial; [NCT02462590]). In this planned secondary analysis of PROSPECT, we performed Cox proportional hazards analyses to assess the sensitivity of the treatment effect of probiotics to coenrollment on the primary outcome of ventilator-associated pneumonia. Secondarily, we examined the characteristics of coenrolled patients, studies, and centers using descriptive statistics, explored factors associated with coenrollment via a multilevel logistic regression model, and conducted Fisher’s exact tests to evaluate the difference in adverse event rates (defined as Lactobacillus species from a sterile site or cultured as the sole or predominant organism from a nonsterile site) by coenrollment status. Of 2650 PROSPECT participants recruited across 44 centers, 568 patients (21.4%) were coenrolled a total of 680 times across 115 studies. Coenrollment did not modify the effect of probiotics on the primary outcome of ventilator-associated pneumonia (p = 0.630). Patients who were coenrolled in any…

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 2,650 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free