Bangladesh Chars Tobacco Assessment Project (CTAP) 2018

Last registered on January 03, 2019


Trial Information

General Information

Bangladesh Chars Tobacco Assessment Project (CTAP) 2018
Initial registration date
October 09, 2018

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
October 09, 2018, 1:58 PM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Last updated
January 03, 2019, 10:39 AM EST

Last updated is the most recent time when changes to the trial's registration were published.



Primary Investigator

BRAC University

Other Primary Investigator(s)

Additional Trial Information

Start date
End date
Secondary IDs
BCCP/Tobacco Control/2018-02
This study aims to look at the effectiveness of advocacy campaigns to reduce tobacco consumption through behavioral nudges in the chars of rural Bangladesh. Two different interventions will be assessed: (1) Repeated nudges through visual warning posters on tobacco intake, and (2) Record keeping of daily tobacco intake to counter non-rational discounting of individual tobacco consumption events. Smoking status of the participants will be assessed though Carbon Monoxide readings for more accurate measures vis-à-vis self-reported tobacco intake. The project aims to target smoking and smokeless tobacco consumption behavior for both males and females.
External Link(s)

Registration Citation

Fakir, Adnan M. S.. 2019. "Bangladesh Chars Tobacco Assessment Project (CTAP) 2018." AEA RCT Registry. January 03.
Former Citation
Fakir, Adnan M. S.. 2019. "Bangladesh Chars Tobacco Assessment Project (CTAP) 2018." AEA RCT Registry. January 03.
Sponsors & Partners

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Experimental Details


The first intervention will provide the participants with two different posters, to be hung near their sleeping arrangement such that it is commonly visible. One of the posters will describe the negative health effects on minors of second hand smoke and the smokers themselves. The other poster will detail the harms to pregnant women and the fetus due to the consumption of smokeless tobacco products. Contrary to visuals on local cigarette packets, none of the posters will feature graphic content but rather will be designed using localized graphic styles such that it is more reflective of their lifestyle, and also contain appealing taglines, highlighting the primary message of the visual content. The posters will be designed to act as a psychological nudge through two channels. First, this intervention hopes to encourage conscious acknowledgement of negative impacts of smoking on a daily basis. Second, by highlighting the impacts on pregnant women and children, the intervention aims to motivate smokers to consider the aggregate impacts of smoking due to associated negative externalities even if they discount costs to oneself.

The second intervention will provide the respondents with a journal to keep a record of the amount of tobacco or tobacco related products consumed daily for the intervention period. This journal will require the respondents to record the number of cigarettes, bidis, and the amount of smokeless tobacco, separately, they consume daily. The data from the journals will not be used for analysis, but rather simply constitutes the intervention. This will act as a nudge by requiring a conscious acknowledgement of the individual's degree of tobacco consumption, allowing them to evaluate their own tobacco spending behavior. Moreover, this intervention will target the non-rational discounting of the aggregate effects of individual tobacco consumption events by allowing better recollection of total consumption over the intervention period.

Both interventions do not coerce individuals in any way to reduce tobacco consumption. Rather, they simply alter the incentive regime through cost-effective nudges.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Weekly Tobacco Expenditure
Primary Outcomes (explanation)
Data on the weekly consumption of tobacco will be used to construct the weekly expenditure measure using the appropriate prices. We want to check if this varies between the baseline and end-line due to the intervention.

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
In order to assess the effectiveness of the interventions described above, two treatment groups and one control group will be formed.Based on a two-stage cluster sampling approach, 24 chars from Gaibandha district will be randomly selected. As we plan on using a Difference-in-Difference (DID) estimator to assess the impact(s) of the treatments, the remoteness of the chars will minimize spillovers. From each of the chars, 42 households will be chosen using simple random sampling. This gives 336 respondents for each group. For each responding household, the head of the household and spouse will be administered the questionnaire.

The baseline questionnaire will follow the standard of the Household Income and Expenditure Survey (HIES) by the Bangladesh Bureau of Statistics (BBS) to collect information regarding tobacco consumption, education, household expenditure, shocks, and other socio-economic conditions. The control groups will be administered the questionnaire only, whereas each treatment group will be informed of the harmful effects of smoking on adults and children and receive the designated treatment. The treatment period will be for 4 weeks following the baseline. A shorter end-line survey will be administered at the end of the treatment period.
Experimental Design Details
Randomization Method
Two-stage cluster randomization done using Stata
Randomization Unit
First stage: Chars (cluster); Second Stage: Households
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
24 chars
Sample size: planned number of observations
1,008 households
Sample size (or number of clusters) by treatment arms
336 households (8 chars) for each of the control and treatment groups.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Accounting for sample design and clustering, the minimum detectable effect size of the main outcome is 0.28 standard deviations.

Institutional Review Boards (IRBs)

IRB Name
James P Grant School of Public Health, BRAC University.
IRB Approval Date
IRB Approval Number


Post Trial Information

Study Withdrawal

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Is the intervention completed?
Intervention Completion Date
December 01, 2018, 12:00 +00:00
Data Collection Complete
Data Collection Completion Date
December 15, 2018, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
24 Clusters
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
985 Households
Final Sample Size (or Number of Clusters) by Treatment Arms
Control Group: 8 Clusters, 317 Households Treatment A: 8 Clusters, 336 Households Treatment B: 8 Clusters, 332 Households
Data Publication

Data Publication

Is public data available?

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Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Objectives: The Chars Tobacco Assessment Project 2018 is a holistic survey conducted in the chars (riverine islands) of Gaibandha in Northern Bangladesh, covering 985 households over 24 clusters. The survey was conducted with two objectives: (1) to assess levels of tobacco consumption and evaluate prevailing socio-economic, behavioral and health status of the chars population, and (2) to look at the effectiveness of advocacy campaigns to reduce tobacco consumption through behavioral nudges via randomized controlled trials (RCTs) in rural Bangladesh. The study site was purposively chosen due to its high tobacco consumption rate, and the geographical segregation of the chars aided in reducing spillovers for RCT design.
Data description: In addition to detailed information on tobacco (smoking and smokeless) consumption and perception, data was collected on: household composition, housing and plot ownership, consumption, risks and shocks coping, dowry, farm production, loans, savings and lending, labor income, asset holdings, migration and remittance, anthropometry, respiratory diseases, co-morbidities, reproductive history, risk and time preference. Unique to the dataset are carbon monoxide readings for accurate short term smoking measurement and FEV1 and PEF values for identification of long term lung damage. The data is representative only for the chars of Gaibandha.
Fakir AMS, Aziz M, Mubde MB, Karim A, Khan AS, Raisa R, Alim LF, Fahmin M. Bangladesh Chars Tobacco Assessment Project (CTAP) 2018: a data note. BMC Research Notes. 2018;11(1):914.

Reports & Other Materials