Clinical Trial Details
— Status: Not yet recruiting
Administrative data
NCT number |
NCT02763527 |
Other study ID # |
GRF |
Secondary ID |
|
Status |
Not yet recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
June 2021 |
Est. completion date |
December 2023 |
Study information
Verified date |
October 2020 |
Source |
The University of Hong Kong |
Contact |
William, Ho Cheung LI, PhD |
Phone |
39176634 |
Email |
william3[@]hku.hk |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Background: Smokers attended to outpatient clinics present an excellent 'teachable moment'
for smoking cessation interventions. This protocol paper describes the rationale and methods
of a large randomized controlled trial which aims to evaluate the effectiveness of
negotiating self-determination to reduce cigarette consumption among smokers attending
outpatient clinics
Methods: A randomized controlled trial will be conducted in 10 out-patient clinics in Hong
Kong. Subjects in the intervention group will receive a brief intervention on smoking
reduction plus a smoking reduction leaflet. Additionally, subjects will be asked to think
about a smoking reduction schedule for themselves after the negotiation with the counsellor.
Subjects in the control group will receive a brief advice on quitting plus a leaflet on
smoking cessation. Four consecutive (1, 3, 6 and 12 months) follow-ups will be conducted. The
primary outcome measure is biochemically validated abstinence at 6 months. Secondary outcomes
are: (i) biochemically validated abstinence at 12 months, (ii) self-reported 7-day point
prevalence of abstinence at 6 and 12 months, (iii) self-reported reduction of ≥ 50% in
cigarette consumption at 6 and 12 months, and (iv) self-efficacy against tobacco at 6 and 12
months.
Description:
This study aims to test the effectiveness of negotiating self-determination to reduce
cigarette consumption (NSD-RCC) among smokers attending outpatient clinics.
Intervention Group (QP) Subjects in this group will receive a brief intervention on smoking
reduction with a warning message plus a smoking reduction leaflet (the content will include a
roadmap of smoking reduction strategy and information on how to cope with nicotine withdrawal
symptoms). The whole intervention will last about 1 minute or slightly longer if necessary.
In addition, subjects will be asked to think about a tailored smoking reduction schedule for
themselves after the negotiation with the trained counsellor. For the subsequent telephone
follow up in the intervention group, information on reduction and cessation will be
collected, followed by a "booster" intervention, which will repeat the health warning to
positively encourage them to reinforce their efforts and the next reduction target.
Control Group (QI) Subjects in the QI group will always be advised to quit immediately rather
than to quit progressively. Subjects will receive a brief advice on quitting with a warning
message similar to subjects in the QP group. In addition, subjects will receive a self-help
quitting pamphlet published by the Hong Kong Council on Smoking and Health (COSH). Unlike the
QP group, subjects in the QI group will not receive smoking reduction intervention and
leaflet, and "booster" intervention during telephone follow-ups. However, they will undergo a
similar schedule of telephone follow-up as those in the QP group.
Data collection
After completing the baseline questionnaire, subjects will receive proposed intervention
according to their group assignment. Four consecutive follow-ups (at 1, 3, 6 and 12 months)
will be conducted over the telephone by trained interviewers. Interviewers will first carry
out outcome assessments with blinding to group status. Then, the group status will be
disclosed so that the intervention group will receive the booster intervention and the
control group will not. Smokers who have successfully quit smoking at 6-month will be invited
to come back to the out-patient clinic and have biochemical validation tests (saliva cotinine
test and exhaled CO test).
Analysis Data analysis will be performed using the Statistical Package for Social Science. We
will compare the baseline characteristics of the participants by chi-square test for
categorical variables and F-test for continuous variables between the intervention and the
control group. We shall use the chi-square test to assess the effect of intervention and
calculate the crude odds ratio (OR) with 95% confidence interval (CI) for the primary and
secondary outcomes. Those who are lost to follow-up or refuse to participate in the
validation tests, will be treated as smokers with no reduction in cigarette consumption
compared with (a) baseline, as the main analysis (by intention to treat), (b) the most recent
level and (c) complete case (per protocol) analysis by excluding subjects with missing data
as a sensitivity analysis.