PERC-Peds Rule Could Change How Children Are Evaluated for Pulmonary Embolism: A PECARN Study

Pulmonary embolism (PE) in children is uncommon, but delayed or missed diagnosis can have serious consequences. Despite this, there is relatively little evidence to guide clinician evaluation of suspected pediatric PE. There are no validated pediatric PE rule-out strategies and adult diagnostic pathways have not been prospectively tested in children.

PECARN sought to change that with their recently published study – BEEPER: Bedside Exclusion of Pulmonary Embolism without Radiation in Children [1]. The investigators developed a rule that safely excluded PE in low-risk children.

Study Objective

The goal of BEEPER was to prospectively evaluate whether the Pulmonary Embolism Rule-out Criteria adapted for children (PERC-Peds) could safely exclude pulmonary embolism in children without the need for laboratory testing or imaging.

What is PERC-Peds?

PERC-Peds was adapted from the adult Pulmonary Embolism Rule-out Criteria (PERC), a well-established adult clinical decision rule used to exclude PE in low-risk patients without additional testing [2]. Using retrospective pediatric data, investigators modified the adult PERC rule to create the pediatric version. A child was considered PERC-Peds negative only if ALL of the following were true:

• Clinician gestalt pretest probability <15%
• No prior PE or proximal DVT
• No surgery requiring intubation within 30 days
• No current estrogen use
• No hemoptysis
• Heart rate always:
  • <100 beats/min if older than 12 years
  • <120 beats/min if 12 years or younger
• Oxygen saturation consistently >94%
• No suspected DVT

Study Design

A Large, Prospective, Multicenter PECARN Study

BEEPER was a multicenter, prospective observational diagnostic accuracy study conducted across 21 emergency departments within PECARN (the Pediatric Emergency Care Applied Research Network).

Inclusion Criteria:

• 4–17 years old, AND
• had suspected PE or proximal DVT prompting clinicians to:
  • order diagnostic testing, OR
  • strongly consider PE in the differential diagnosis

Eligible diagnostic testing included:

• D-dimer
• CT pulmonary angiography (CTPA)
• V/Q scan
• MRI angiography
• Other pulmonary vascular imaging

All testing decisions remained entirely at clinician discretion.

Outcome Definition

The outcome was venous thromboembolism (VTE), including:

• image-confirmed pulmonary embolism, OR
• proximal DVT (above knee or elbow)

Results

Enrollment

• 4,039 children enrolled, 3,988 had analyzable data

Prevalence of Disease

Overall:

• 254 children (6.3%) had PE and/or proximal DVT

Breakdown:

• Isolated proximal DVT: 76
• Both PE and proximal DVT: 56
• Isolated PE: 122

Performance of PERC-Peds

The PERC-Peds rule demonstrated extremely high diagnostic sensitivity.

Diagnostic Accuracy

• Sensitivity: 99.6% (95% CI 97.8–99.9%)
• Specificity: 19.6% (95% CI 18.4–21.0%)
• False negative rate: 0.1% (95% CI 0–0.75%)
• Negative predictive value: 99.9%

There was only ONE false negative. These findings suggest that PERC-Peds can safely exclude PE in a subset of low-risk children without additional laboratory testing or imaging.

D-Dimer Findings

BEEPER also provided the first large prospective evaluation of D-dimer performance in children undergoing PE evaluation. Clinicians ordered D-dimer testing in approximately 75–79% of enrolled children. Using a standardized threshold of 500 ng/mL:

• Sensitivity: 88.8%
• Specificity: 61.9%
• False negative rate: 1.2–1.4%

These data support the use of D-dimer as part of a sequential diagnostic strategy in pediatric PE evaluation for those children who fail PERC-Peds.

PERC-Peds + D-Dimer Sequential Strategy

One of the most clinically important findings was the potential value of combining:

• PERC-Peds
• followed by D-dimer if PERC-Peds failed

This sequential strategy would have:

• safely excluded PE in 54.7% of enrolled children,
• excluded PE in 69% of children who had D-dimer ordered,
• maintained an acceptable false negative rate of 1.0% (95% CI 0.6–1.5%),
• estimated reduction in CT pulmonary angiography use by approximately 18.5%.

Putting PERC-Peds in Context

The PERC-Peds rule performed well compared to the regularly utilized adult PERC rule. Adult PERC studies [2] typically show sensitivities around 95% with false negative rates below 2%, while in BEEPER, the sensitivity approached 100% with an exceptionally low false negative rate. Just as importantly, this is the first prospective study to support a bedside rule-out strategy for PE in children: offering a potential pathway to safely reduce unnecessary CT scans and radiation exposure in low-risk patients. BEEPER also lays the groundwork for a more standardized pediatric PE evaluation approach, where clinicians could use PERC-Peds first, followed by D-dimer testing when needed, reserving imaging for children at higher risk.

What’s Next?

While BEEPER represents a major step forward in pediatric PE diagnosis, the study also highlights important limitations and unanswered questions. PERC-Peds demonstrated high sensitivity, but relatively low specificity: meaning many children will still fail the rule, and indiscriminate use could potentially increase testing. Importantly, BEEPER was an observational diagnostic study, meaning it did not evaluate outcomes from the implementation of a clinical decision rule.

BEEPER provides the foundation for a new era of pediatric PE evaluation research. Future studies will likely focus on implementation science: understanding whether use of PERC-Peds changes clinician behavior, safely reduces imaging, and can be integrated into real-world emergency department workflows. Investigators also envision future diagnostic algorithms that combine PERC-Peds with D-dimer testing to reserve imaging for children at highest risk, potentially reducing unnecessary radiation exposure in a meaningful number of patients. Additional work can evaluate performance across different clinical settings, refine the gestalt component of the rule, and explore integration into electronic health record decision support tools. Taken together, BEEPER fills one of the most important evidence gaps in pediatric emergency medicine and represents the first major step toward safer, more standardized, and evidence-based pediatric PE evaluation.

References

1. Ellison AM, Kuppermann N, Shihabuddin BS, et al. PERC-Peds rule for bedside exclusion of pulmonary embolism without radiation in children in the USA (BEEPER): a multicentre, prospective, observational, diagnostic accuracy study. Lancet Respir Med. Published online July 2026. doi:10.1016/S2213-2600(26)00086-X.
2. Kline JA, Courtney DM, Kabrhel C, et al. Prospective multicenter evaluation of the pulmonary embolism rule-out criteria. J Thromb Haemost. 2008;6(5):772-780. doi:10.1111/j.1538-7836.2008.02944.x. PMID: 18318689.