Fewer Tests to Rule Out Blood Clots in the Lungs in Children: The PECARN BEEPER Study

A blood clot in the lungs, called a pulmonary embolism (PE), is uncommon in children. But when it is missed, the consequences can be serious. Until now, doctors have had little tested guidance for evaluating a child with possible PE, and no simple bedside way to decide who can safely skip blood tests and imaging.

A new PECARN study called BEEPER (Bedside Exclusion of Pulmonary Embolism without Radiation in Children), published in The Lancet Respiratory Medicine, set out to change that. It tested whether a short bedside checklist could safely rule out PE in low-risk children without any labs or scans [1].

What the Study Tested

The checklist is called PERC-Peds, a children’s version of a rule long used in adults [2]. A child is considered low-risk only if all eight of these are true:

  1. The clinician’s overall judgment puts the risk of PE below 15%
  2. No prior PE or proximal deep vein clot (DVT)
  3. No surgery requiring a breathing tube in the last 30 days
  4. No current estrogen use
  5. No coughing up blood
  6. Heart rate below 100 (over age 12) or below 120 (age 12 and under)
  7. Oxygen level consistently above 94%
  8. No suspected DVT

Study Design

BEEPER enrolled 3,988 children ages 4 to 17 with suspected PE across 21 emergency departments in PECARN (the Pediatric Emergency Care Applied Research Network). It is the first large, prospective test of a bedside rule-out strategy for PE in children.

Results

  • Of the children evaluated, 254 (6.3%) turned out to have a clot.
  • When a child passed all eight PERC-Peds checks, the rule was highly reliable: 99.6% sensitive. Only one child who passed later turned out to have a clot.
  • About 1 in 5 children could be cleared by the checklist alone, with no blood test or scan.
  • For children who did not pass, adding a simple blood test (D-dimer) as the next step could rule out most of the rest. Using the checklist first, then D-dimer, would have safely cleared about 55% of all children and cut CT scans by roughly 18.5%.

Why This Matters

The usual test for PE is a CT scan, which uses radiation. That radiation carries a small long-term cancer risk that matters more in children than in adults. A reliable way to identify low-risk children who do not need a scan means fewer unnecessary tests, less radiation, and faster care. BEEPER is the first prospective evidence supporting this kind of bedside approach in children.

Two cautions come with the findings. BEEPER watched how the rule performed but did not test what happens when clinicians actually use it to make decisions, so the next step is putting it into practice. And because many children will not pass the checklist and go on to further testing, the rule is meant to support clinical judgment, not replace it.

Take Home Message

For children being evaluated for a possible blood clot in the lungs, a short bedside checklist (PERC-Peds) can safely identify those at low enough risk to skip further testing. Children who pass every item need no blood test and no CT scan; for those who do not, a single blood test can still spare many of them a scan. It is a practical step toward safer, more consistent, lower-radiation care.

Why is this important for patients and caregivers

  • A pulmonary embolism is a blood clot in the lungs. It is rare in children but can be serious if missed.
  • Checking for it often means blood tests and a CT scan, which uses radiation. This study found a simple set of bedside questions that can safely tell which children are low-risk and may not need those tests.
  • If your child is being evaluated for a possible clot, the care team may use this checklist, sometimes with a single blood test, to decide whether a CT scan is needed. The goal is fewer tests and less radiation without missing a dangerous clot.

This blog post is a summary of the following journal publication:
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

Interested in other PECARN research?

A few recent PECARN studies covered on the PECARN and ALiEM blogs:

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. PMID: 18318689. doi:10.1111/j.1538-7836.2008.02944.x
Michelle Lin, MD

Michelle Lin, MD

Professor of Emergency Medicine, University of California, San Francisco

This website is supported by the Health Resources and Services Administration (HRSA) of the U.S. Department of Health and Human Services (HHS) as part of the Emergency Medical Services for Children Data Center award totaling $3,200,000 with 0% financed with non-governmental sources. The contents are those of the author(s) and do not necessarily represent the official views of, nor an endorsement, by HRSA, HHS, or the U.S. Government. For more information, please visit HRSA.gov.

PECARN is committed to making health care information accessible for everyone. Please contact melissa.laws@hsc.utah.edu if you encounter a document, such as an older PDF brochure or historical form, that has not been optimized for your screen reader. We consider these remediation requests a top priority and will provide an accessible version as soon as possible.