Oral adverse event reporting in smoking cessation trials using non-combustible nicotine products: A quality assessment

Abstract

Objectives: To assess the completeness and quality of reporting of oral adverse events (OAEs) in randomized controlled trials (RCTs) that evaluated non-combustible nicotine products (NCNPs) and whether reporting practices have improved over time.

Data sources and study selection: This secondary data analysis was based on 36 RCTs included in a previous systematic review. Trials involved adult smokers and included nicotine replacement therapy, electronic cigarettes, heated tobacco, and smokeless tobacco. The OAE reporting was evaluated using an adapted CONSORT Harms checklist. An Adjusted Checklist Score (ACS), representing the proportion of criteria met, was calculated. Univariate linear regressions explored the association between ACS and study-level variables (publication year, country, funding, blinding and product type).

Results: OAE reporting was fragmented, with a mean ACS of 0.52 (0.11-0.74). Over 80 % of studies (n=30) provided some quantitative data, but only 53 % (n=19) presented results in a tabulated, arm-specific format. Definitions of OAEs and severity measurement were rarely reported (n=5, 14 % and n=6, 17 % respectively). The method of OAEs collection was described in 50 % of the studies (n=18). OAEs were rarely mentioned in titles (n=4, 11 %) and conclusions (n=13, 36 %). Less than half of the studies reported the reasons for participant withdrawal due to AEs (n=16, 44 %). Only 28 % (n=10) and 44 % (n=16) of the studies reported the analysis approach and statistical methods for AEs, respectively. A weak, non-significant positive correlation was found between ACS and year of publication (r = 0.288, p = 0.09). No study-level variable showed a statistically significant association with ACS.

Conclusions: Reporting of OAEs in clinical trials of NCNPs remains limited and inconsistent, often lacking clear definitions, standardized severity assessments, detailed data collection methods, and predefined statistical plans.

Clinical significance: Standardized OAE reporting is critical for tolerability data interpretation. We propose practical recommendations to guide researchers in improving the reporting of OAE and strengthening the role of dental professionals in supporting patients through smoking cessation strategies.