Evidence map›Paper›PMID 32097445›Full record

ArticlePloS one2020

Lung clearance index in healthy volunteers, measured using a novel portable system with a closed circuit wash-in.

Alex R Horsley, Amnah Alrumuh, Brooke Bianco, Katie Bayfield, Joanne Tomlinson, Andrew Jones, Anirban Maitra, Steve Cunningham, Jaclyn Smith, Catherine Fullwood and 2 more

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.5field-weighted citation impact, top 31% of its field
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

2 citing papers in PubMed, 7 citations in OpenAlex.

  1. Pulmonary exacerbations in primary ciliary dyskinesia.European journal of pediatrics · 2026
    Review
  2. Article
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

12 authors at 6 institutions in 1 country.

Alex R HorsleyDivision of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.ORCID 0000-0003-1828-0058
Amnah AlrumuhInstitute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom.
Brooke BiancoManchester Adult CF Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
Katie BayfieldNIHR Manchester Clinical Research Facility, Manchester, United Kingdom.ORCID 0000-0003-3587-4763
Joanne TomlinsonRoyal Stoke University Hospital, University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, United Kingdom.
Andrew JonesDivision of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.
Anirban MaitraRoyal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
Steve CunninghamCentre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom.
Jaclyn SmithDivision of Infection, Immunity & Respiratory Medicine, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom.
Catherine FullwoodResearch and Innovation, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
Anand PandyanInstitute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom.
Francis J GilchristInstitute of Applied Clinical Science, Keele University, Newcastle-under-Lyme, United Kingdom.
University of Manchester · GBUniversity Hospitals of North Midlands NHS Trust · GBManchester University NHS Foundation Trust · GBCentre for Inflammation Research · GBKeele University · GBNIHR Manchester Biomedical Research Centre · GB

Funding

Department of Health NIHR-CS-012-013Wellcome Trust 207504/B/17/Z
6 · The paper itself

Abstract

introductionLung clearance index (LCI) is a sensitive measure of early lung disease, but adoption into clinical practice has been slow. Challenges include the time taken to perform each test. We recently described a closed-circuit inert gas wash-in method that reduces overall testing time by decreasing the time to equilibration. The aim of this study was to define a normative range of LCI in healthy adults and children derived using this method. We were also interested in the feasibility of using this system to measure LCI in a community setting.

methodsLCI was assessed in healthy volunteers at three hospital sites and in two local primary schools. Volunteers completed three washout repeats at a single visit using the closed circuit wash-in method (0.2% SF6 wash-in tracer gas to equilibrium, room air washout).

results160 adult and paediatric subjects successfully completed LCI assessment (95%) (100 in hospital, 60 in primary schools). Median coefficient of variation was 3.4% for LCI repeats and 4.3% for FRC. Mean (SD) LCI for the analysis cohort (n = 53, age 5-39 years) was 6.10 (0.42), making the upper limit of normal LCI 6.8. There was no relationship between LCI and multiple demographic variables. Median (interquartile range) total test time was 18.7 (16.0-22.5) minutes.

conclusionThe closed circuit method of LCI measurement can be successfully and reproducibly measured in healthy volunteers, including in out-of-hospital settings. Normal range appears stable up to 39 years. With few subjects older than 40 years, further work is required to define the normal limits above this age.

Indexed as

Forced Expiratory VolumeAdolescentAdultChildChild, PreschoolFemaleFunctional Residual CapacityHealthy VolunteersHumansLungMaleMetabolic Clearance RateMiddle AgedRespiratory Function TestsYoung Adult

Identifiers

PMID32097445
PMCPMC7041809
OpenAlexW3008483234

What OpenQuestion 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 OpenQuestion graph.