Evidence map›Paper›PMID 41248153›Full record

SynthesisPloS one2025

Association of ambulance and helicopter response times with patient survival: A systematic literature review and meta-analysis.

Peter Martin Hansen, Martine Siw Nielsen, Marius Rehn, Annmarie Lassen, Anders Perner, Søren Mikkelsen, Anne Craveiro Brøchner

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in PloS one, 2025. 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

7 authors.

Peter Martin HansenPrehospital Research Unit, Region of Southern Denmark, Odense, Denmark.ORCID https://orcid.org/0000-0002-8065-5765
Martine Siw NielsenDepartment of Regional Health Research, University of Southern Denmark, Odense, Denmark.
Marius RehnPrehospital Research Unit, Region of Southern Denmark, Odense, Denmark.
Annmarie LassenDepartment of Emergency Medicine, Odense University Hospital, Odense, Denmark.
Anders PernerDepartment of Anesthesiology and Intensive Care Medicine, Rigshospitalet, Copenhagen, Denmark.
Søren MikkelsenPrehospital Research Unit, Region of Southern Denmark, Odense, Denmark.ORCID https://orcid.org/0000-0002-5187-7027
Anne Craveiro BrøchnerPrehospital Research Unit, Region of Southern Denmark, Odense, Denmark.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundOnly sparse scientific evidence supports the notion that the shortest possible response time relates to improved patient outcomes in acute conditions, other than out-of-hospital cardiac arrest and trauma. Confounders such as bidirectional causality and confounding by indication may influence patient-centered outcomes, which may prevent actionable conclusions from literature reviews. The purpose of the systematic literature review was to assess current evidence on association, if any, between ambulance and helicopter response times and survival in all patient categories treated by ambulance or helicopter services.

methodsThe systematic search was conducted in MEDLINE, Cochrane Library, EMBASE, CINAHL, Scopus, and Clinical Trial Registries. All study designs and settings identified as relevant to the topic were eligible. The investigators retrieved data from a predefined template and extracted data from a predefined template. Two reviewers worked independently, and conflicts were resolved by a third reviewer. The researchers used PRISMA guidelines for abstracting data and GRADE methodology for assessing data quality and validity. As per study protocol, the primary study outcome was patient survival, and the main measurement was response time for emergency medical services vehicles.

resultsThe investigators included 115 studies that in total included 691,056 patients, comprising patients with out-of-hospital cardiac arrest, trauma, drownings, and including both adults and children in various settings. The overall median survival rate was 11.5% (IQR 5.2; 25.8). Response time varied between 1.10 and 48.62 minutes. The predefined domains and items of interest were accounted for in 46.7% of the included literature. In a meta-analysis of sub-groups, there was a positive correlation in selected populations. Certainty of evidence was very low as per GRADE methodology.

conclusionsThis systematic review and meta-analysis found lack of evidence to infer an association between the EMS response time and patient survival, with very low certainty of evidence. The investigators found substantive research and knowledge gaps. Therefore, no actionable conclusions can be made from this systematic review.

Indexed as

Air AmbulancesAmbulancesEmergency Medical ServicesOut-of-Hospital Cardiac ArrestHumansTime Factors

Identifiers

PMID41248153
PMCPMC12622838

What Socratic holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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 Socratic graph.