
PMID- 42552006
OWN - NLM
STAT- MEDLINE
DCOM- 20260804
LR  - 20260819
IS  - 2044-6055 (Electronic)
IS  - 2044-6055 (Linking)
VI  - 16
IP  - 8
DP  - 2026 Aug 4
TI  - Changes in knowledge of the major harms of tobacco smoking and secondhand smoke 
      exposure among adults who smoke: findings from 26 countries of the International 
      Tobacco Control (ITC) Project (2002-2022) and 32 countries of the Global Adult 
      Tobacco Survey (GATS) (2008-2020).
PG  - e107667
LID - 10.1136/bmjopen-2025-107667 [doi]
LID - e107667
AB  - OBJECTIVES: To assess levels of and trends in knowledge that smoking and 
      secondhand smoke (SHS) cause lung cancer and cardiovascular disease (CVD) in 46 
      countries over two decades. DESIGN: Longitudinal cohort and repeat 
      cross-sectional surveys. SETTING: Nationally representative surveys in 26 
      International Tobacco Control (ITC) Project countries (2002-2022) and 32 Global 
      Adult Tobacco Survey (GATS) countries (2008-2020). PARTICIPANTS: Adults (aged 18+ 
      years) who smoke tobacco (26 ITC countries: n=133 410; 32 GATS countries: n=110 
      537). ANALYSIS OUTCOMES: Current use of cigarettes at least monthly (all ITC 
      countries) and/or bidis at least monthly (ITC India, Bangladesh and Zambia) and 
      current use of any combustible tobacco products (all GATS countries). We 
      conducted individual-level analyses of the ITC and GATS data separately, without 
      combining the datasets or analysing previously published summary statistics. 
      Generalised estimating equations and weighted multinomial regression models 
      assessed country-level prevalence of knowledge for three smoking and two SHS 
      outcomes. Multilevel models estimated mean prevalence across all countries and 
      tested within-country linear trends over time for five disease indicators by 
      survey. Across 12 countries with data from both surveys, correlations between ITC 
      and GATS assessed consistency across indicators. RESULTS: Knowledge that smoking 
      causes lung cancer was highest (ITC=92.2%, GATS=91.9%), followed by heart disease 
      (ITC=84.7%)/heart attack (GATS=80.0%) and stroke (ITC=75.0%, GATS=66.1%). 
      Knowledge that SHS causes lung cancer (ITC=77.3%, GATS=82.1%) was highest, 
      followed by heart attack (ITC=61.8%)/heart disease (GATS=72.5%) (all p<0.0001). 
      In ITC and GATS countries, the average change in knowledge across the five 
      diseases was +0.14% per year. There was agreement between the ITC and GATS data 
      (range: Pearson correlations=0.60-0.81 across the five indicators). CONCLUSIONS: 
      There is a need to improve and sustain people's knowledge of diseases caused by 
      smoking and SHS, especially CVD risks.
CI  - (c) Author(s) (or their employer(s)) 2026. Re-use permitted under CC BY. Published 
      by BMJ Group.
FAU - Chung-Hall, Janet
AU  - Chung-Hall J
AUID- ORCID: 0000-0002-9139-8100
AD  - School of Psychology, University of Waterloo, Waterloo, Ontario, Canada 
      jchunghall@uwaterloo.ca.
FAU - Fong, Geoffrey T
AU  - Fong GT
AUID- ORCID: 0000-0001-9098-6472
AD  - School of Psychology, University of Waterloo, Waterloo, Ontario, Canada.
AD  - School of Public Health Sciences, University of Waterloo, Waterloo, Ontario, 
      Canada.
AD  - Ontario Institute for Cancer Research, Toronto, Ontario, Canada.
FAU - Meng, Gang
AU  - Meng G
AUID- ORCID: 0000-0002-7771-7881
AD  - School of Psychology, University of Waterloo, Waterloo, Ontario, Canada.
FAU - Craig, Lorraine V
AU  - Craig LV
AD  - School of Psychology, University of Waterloo, Waterloo, Ontario, Canada.
FAU - Indome, Eunice O
AU  - Indome EO
AUID- ORCID: 0009-0008-0732-8419
AD  - School of Psychology, University of Waterloo, Waterloo, Ontario, Canada.
CN  - ITC Project Collaborators
FAU - Kress, Alissa C
AU  - Kress AC
AUID- ORCID: 0000-0002-6601-7097
AD  - National Center for Chronic Disease Prevention and Health Promotion, Office on 
      Smoking and Health, Atlanta, Georgia, USA.
FAU - Shi, Jing
AU  - Shi J
AUID- ORCID: 0009-0004-7782-5323
AD  - National Center for Chronic Disease Prevention and Health Promotion, Office on 
      Smoking and Health, Atlanta, Georgia, USA.
AD  - Noninfectious Disease Programs, CDC Foundation Inc, Atlanta, Georgia, USA.
FAU - Ahluwalia, Indu B
AU  - Ahluwalia IB
AUID- ORCID: 0000-0001-5985-3356
AD  - National Center for Chronic Disease Prevention and Health Promotion, Office on 
      Smoking and Health, Atlanta, Georgia, USA.
LA  - eng
GR  - C312/A6465/CRUK_/Cancer Research UK/United Kingdom
GR  - R01-CA090955/US NCI National Cancer Institute/
GR  - C312/A3726/CRUK_/Cancer Research UK/United Kingdom
GR  - C25586/A19540/CRUK_/Cancer Research UK/United Kingdom
GR  - P01 CA138389/CA/NCI NIH HHS/United States
GR  - R01-CA100362/US NCI National Cancer Institute/
GR  - C321/A11039/CRUK_/Cancer Research UK/United Kingdom
GR  - P01-CA200512/US NCI National Cancer Institute/
GR  - P50-CA111236/US NCI National Cancer Institute/
GR  - R01 CA125116/CA/NCI NIH HHS/United States
GR  - P50 CA111236/CA/NCI NIH HHS/United States
GR  - R01 CA100362/CA/NCI NIH HHS/United States
GR  - P01 CA200512/CA/NCI NIH HHS/United States
GR  - P50-CA111236/CA/NCI NIH HHS/United States
GR  - R01-CA125116/US National Cancer Institute at the National Institutes of Health/
GR  - R01 CA090955/CA/NCI NIH HHS/United States
GR  - R01-CA125116/CA/NCI NIH HHS/United States
PT  - Journal Article
DEP - 20260804
PL  - England
TA  - BMJ Open
JT  - BMJ open
JID - 101552874
RN  - 0 (Tobacco Smoke Pollution)
SB  - IM
MH  - Humans
MH  - *Tobacco Smoke Pollution/adverse effects
MH  - *Tobacco Smoking/adverse effects/epidemiology
MH  - *Health Knowledge, Attitudes, Practice
MH  - Adult
MH  - Male
MH  - Cross-Sectional Studies
MH  - Female
MH  - Middle Aged
MH  - Longitudinal Studies
MH  - Lung Neoplasms/etiology
MH  - *Cardiovascular Diseases/etiology
MH  - Young Adult
MH  - Global Health
MH  - Adolescent
PMC - PMC13479502
OTO - NOTNLM
OT  - Health
OT  - PUBLIC HEALTH
OT  - Tobacco Use
FIR - Andler, Raphael
IR  - Andler R
FIR - Bansal-Travers, Maansi
IR  - Bansal-Travers M
FIR - Barrientos-Gutierrez, Tonatiuh
IR  - Barrientos-Gutierrez T
FIR - Boado, Marcelo
IR  - Boado M
FIR - Burhoo, Premduth
IR  - Burhoo P
FIR - Michael Cummings, K
IR  - Michael Cummings K
FIR - Perez, Cristina de Abreu
IR  - Perez CA
FIR - Demjen, Tibor
IR  - Demjen T
FIR - East, Katherine A
IR  - East KA
FIR - Edwards, Richard
IR  - Edwards R
FIR - Fernandez, Esteve
IR  - Fernandez E
FIR - Fu, Marcela
IR  - Fu M
FIR - Gartner, Coral E
IR  - Gartner CE
FIR - Goma, Fastone M
IR  - Goma FM
FIR - Gupta, Prakash C
IR  - Gupta PC
FIR - Ghulam Hussain, A K M
IR  - Ghulam Hussain AKM
FIR - Hyland, Andrew
IR  - Hyland A
FIR - Ikamari, Lawrence
IR  - Ikamari L
FIR - Jampaklay, Aree
IR  - Jampaklay A
FIR - Jiang, Yuan
IR  - Jiang Y
FIR - Katanoda, Kota
IR  - Katanoda K
FIR - Kim, Gil-Yong
IR  - Kim GY
FIR - Kim, Su Young
IR  - Kim SY
FIR - Lee, Sungkyu
IR  - Lee S
FIR - Hairi, Farizah Mohd
IR  - Hairi FM
FIR - Mons, Ute
IR  - Mons U
FIR - Nargis, Nigar
IR  - Nargis N
FIR - Nordin, Amer Siddiq Amer
IR  - Nordin ASA
FIR - Ong'ang'o, Jane Rahedi
IR  - Ong'ang'o JR
FIR - Omar, Maizurah
IR  - Omar M
FIR - Pednekar, Mangesh S
IR  - Pednekar MS
FIR - Przewozniak, Krzysztof
IR  - Przewozniak K
FIR - Seo, Hong Gwan
IR  - Seo HG
FIR - Thrasher, James F
IR  - Thrasher JF
FIR - Trofor, Antigona
IR  - Trofor A
FIR - Vardavas, Constantine I
IR  - Vardavas CI
FIR - Waa, Andrew M
IR  - Waa AM
FIR - Willemsen, Marc C
IR  - Willemsen MC
FIR - Wilson, Nick
IR  - Wilson N
FIR - Zatonski, Witold A
IR  - Zatonski WA
EDAT- 2026/08/05 18:38
MHDA- 2026/08/05 18:39
PMCR- 2026/08/04
CRDT- 2026/08/04 20:53
PHST- 2026/08/05 18:39 [medline]
PHST- 2026/08/05 18:38 [pubmed]
PHST- 2026/08/04 20:53 [entrez]
PHST- 2026/08/04 00:00 [pmc-release]
AID - bmjopen-2025-107667 [pii]
AID - 10.1136/bmjopen-2025-107667 [doi]
PST - epublish
SO  - BMJ Open. 2026 Aug 4;16(8):e107667. doi: 10.1136/bmjopen-2025-107667.
