Evidence map›Paper›PMID 37832989›Full record

Trial reportBMJ open2023

Evaluating the impact of varying expired carbon monoxide thresholds on smoking relapse identification: insights from the E3 trial on e-cigarette efficacy for smoking cessation.

Celine Prell, Andréa Hébert-Losier, Kristian B Filion, Pauline Reynier, Mark J Eisenberg

Registry-linked trialAbstract readRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in BMJ open, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT02417467 (Evaluating the Efficacy of E-Cigarette Use for Smoking Cessation), which is not on this map. Cited by 4 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed, 3 pooled it
–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.

NCT02417467 phase3completednot on this map

Evaluating the Efficacy of E-Cigarette Use for Smoking Cessation (E3) Trial

TypeinterventionalSponsorMcGill UniversityRan2016 to 2020Enrolled376ConditionsSmoking CessationArmsNicotine E-Cigarette, Non-Nicotine E-Cigarette, Counseling
3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 3 syntheses or guidelines pooled it.

  1. Electronic cigarettes for smoking cessation.The Cochrane database of systematic reviews · 2026
    Pooled it
  2. Electronic cigarettes for smoking cessation.The Cochrane database of systematic reviews · 2025
    Pooled it
  3. Electronic cigarettes for smoking cessation.The Cochrane database of systematic reviews · 2025
    Pooled it
  4. 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

5 authors.

Celine PrellCentre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital/McGill University, Montreal, QC, Canada.
Andréa Hébert-LosierCentre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital/McGill University, Montreal, QC, Canada.
Kristian B FilionCentre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital/McGill University, Montreal, QC, Canada.ORCID 0000-0001-6055-0088
Pauline ReynierCentre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital/McGill University, Montreal, QC, Canada.
Mark J EisenbergCentre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital/McGill University, Montreal, QC, Canada mark.eisenberg@ladydavis.ca.ORCID 0000-0002-1296-0661

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesExpired carbon monoxide (ECO) is often used in smoking cessation trials to biochemically validate self-reported smoking status. The optimal ECO threshold to distinguish individuals who smoke from those who do not is debated.

designThe data from the 'Evaluating the Efficacy of E-Cigarette use for Smoking Cessation (E3) Trial' were used; the E3 trial was a randomised controlled trial that examined e-cigarettes efficacy for smoking cessation. SETTINGS: Participants were recruited from 17 Canadian sites across 4 provinces.

participantsThis substudy included data from participants who returned for at least one of the clinical visits at week 4 (291), 12 (257) or 24 (218) and provided both self-reported smoking status and ECO measures. Analyses were based on 766 paired measures (ie, self-reported smoking status with corresponding ECO).

resultsThe ability of ECO measurements to discriminate between adults who reported smoking and those who reported abstinence varied with the threshold used. ECO thresholds of 6, 7, 8 and 9 parts per million (ppm) yielded the greatest area under the receiver operating characteristic curve (0.84). These thresholds produced sensitivities of 84%, 82%, 78% and 76% and specificities of 84%, 87%, 90% and 91%, respectively. However, at a threshold of 6 ppm, intersecting sensitivity (84%) and specificity (84%) were maximised with respect to each other. Biochemical validation had the highest agreement with self-report at an ECO threshold of 6 ppm (κ=0.57; 95% CI, 0.51 to 0.64).

conclusionThe classification of participants' smoking status depends on the ECO threshold used for biochemical validation. We recommend that future smoking cessation trial investigators analyse and report the impact that varying ECO thresholds has on trial results. TRIAL REGISTRATION NUMBER: NCT02417467.

Indexed as

Electronic Nicotine Delivery SystemsSmoking CessationVapingAdultCanadaCarbon MonoxideHumansCarbon Monoxideclinical trialsepidemiologic studiespublic health

Identifiers

PMID37832989
PMCPMC10583027

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

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.