Evidence map›Paper›PMID 42876058›Full record

ArticleJournal of applied clinical medical physics2026

Automated linac downtime tracking across 4 radiation oncology clinics within a single hospital system utilizing statistical process control.

Caroline E Serafini, Matthew Thomas, Xiaofeng Yang, Pretesh Patel, Justin Roper, Maxine Washington, Anees Dhabaan, Hania Al-Hallaq

Abstract read
In one paragraph

Article in Journal of applied clinical medical physics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Caroline E SerafiniDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.ORCID https://orcid.org/0000-0002-6512-5977
Matthew ThomasDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.
Xiaofeng YangDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.ORCID https://orcid.org/0000-0001-9023-5855
Pretesh PatelDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.
Justin RoperDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.ORCID https://orcid.org/0009-0004-1729-4444
Maxine WashingtonDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.
Anees DhabaanDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.ORCID https://orcid.org/0000-0002-6426-2443
Hania Al-HallaqDepartment of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, USA.ORCID https://orcid.org/0000-0003-4274-6524

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundLinear accelerator (linac) downtime disrupts clinical workflow and may delay patient treatment; however, downtime events are frequently undocumented or recorded in informal reporting systems. Data-driven approaches using routinely collected operational metrics may improve downtime surveillance and provide insight into system-level adaptation. PURPOSE: This study aims to evaluate if statistical process control (SPC) methods can be applied to routine treatment and scheduling data from an oncology information system (OIS) to identify linac downtime events and characterize operational response across multiple radiation oncology clinics within a single hospital system.

methodsDaily machine-level operational data from 10 linacs across 4 clinics were analyzed over 29 months (January 2024-May 2026). Machine metrics included daily patient volume, cancellations, and operating hours. For each machine, rolling 45-day baseline means and standard deviations were computed, and SPC rules (± 3σ control limits and > 10 cancellations / day) were applied to detect downtime days. SPC-flagged events were compared with email-based downtime event logs to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Downtime events were categorized by cause, and intra-hospital patient redistribution was assessed by identifying concurrent > 4σ volume increases on alternate machines.

resultsOver the 29-month study period, 138 downtime events were documented in downtime event logs. SPC identified 23 additional events exhibiting operational signatures consistent with downtime. Using reported events as the reference standard, SPC achieved sensitivity 0.70, specificity 0.99, PPV 0.79, and NPV 0.99. Downtime frequently resulted in compensatory increases in patient volume on alternate machines, with 41 transfer pairs identified across three hospitals. When the reported downtime cause was specified, machine mechanical causes accounted for the largest proportion (48%) of downtime events.

conclusionsSPC applied to routinely collected operational data provides a scalable framework for automated linac downtime detection. Integration of automated monitoring with structured reporting may improve downtime surveillance and inform proactive operational planning in radiation oncology.

Indexed as

NeoplasmsParticle AcceleratorsRadiation OncologyRadiotherapy Planning, Computer-AssistedWorkflowHumansRadiotherapy DosageRadiotherapy, Intensity-Modulateddowntime surveillancelinear acceleratorstatistical process control

Identifiers

PMID42876058
PMCPMC13669665

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.