Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02522156 |
| Other study ID # |
American_University |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
February 2016 |
| Est. completion date |
December 2019 |
Study information
| Verified date |
January 2020 |
| Source |
American University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Almost one-fifth of US adults are current cigarette smokers. To make further progress in
lowering prevalence, it would help to increase the proportion of smokers attempting to quit.
This application tests a novel approach to motivating smokers to quit, based on an
empirically supported theory of anxiety. The approach uses guided imagery to increase
smokers' sense of urgency about preventing the negative health consequences of smoking.
Description:
Approach Participants and Eligibility Criteria
The investigators plan to enroll 290 participants, recruited via newspaper, radio, and online
ads, flyers distributed in the community, and letters to healthcare providers. Ads will
recruit adults who smoke at least 10 cigarettes/day and are willing to participate in two
sessions four weeks apart but will not mention smoking cessation.
Prospective participants must meet the following criteria at a phone screen:
1. Adults (age 18 or older).
2. Daily cigarette smokers (at least 10 cigarettes per day).
3. Total score of 5 or below on the Modified Mini Screen and score of 0 on the suicidality
item.
4. Fluent in English.
5. Not planning to leave the Washington, DC area in the next month.
The Modified Mini Screen (MMS) is a safety precaution for the looming vulnerability
induction, which on average increases state anxiety. Those scoring 6 or higher on the MMS are
considered at moderate to high risk of having anxiety, mood, or psychotic disorders. The MMS
is a modification of the MINI and appears to work equally well for men and women and for
Caucasians and African Americans; the investigators are using the lowest (most conservative)
cutoff score recommended on the basis of research validating the MMS against a full
diagnostic interview (SCID). Prospective participants excluded on this basis will be offered
therapy in a departmental training clinic, as well as alternate local referrals, outside the
context of this research project.
Fluency in English is necessary for valid completion of our assessments. Planning to remain
in the metropolitan area should help to lower the attrition rate.
Procedure
Eligible participants who choose to enroll in the study will be scheduled for an in-person
assessment and imagery experiment. The following chart shows measures completed at each
assessment:
Measure Experiment 4-week follow-up Expired air CO X X State anxiety (VAS) X (pre/post
imagery induction) Demographics X Smoking and smoking cessation history X Nicotine Dependence
(FTND) X X Visualization ability (VVIQ) X Contemplation Ladder X X Stage of change algorithm
X X Current (past month) smoking rate X X Self-efficacy (SSEQ) X X Outcome expectancies
(SCQ-A) X X Most accessible outcome expectancy (SGO) X X Vividness rating of imagery X
Perception of health consequences of smoking as looming (CSCLS-P) X Quit attempt (>= 24
hours) X Description of quit attempt methods used, length, etc. X Sensation Seeking (SSS-V) X
First session: Baseline assessment and experiment on looming vulnerability induction. After
completing informed consent, participants will complete an expired air CO test to corroborate
smoker status (>= 9 ppm). If smoker status is not confirmed, they will be paid for their time
and excused as ineligible. Participants who are eligible and interested will complete
baseline measures in one of four random orders:
Visual Analogue Scale (VAS) for state anxiety. State anxiety will be measured with a
single-item VAS in which the participant makes a mark along a 100 mm horizontal line anchored
by the phrase "Not at All" at the left (0) and "Extremely" at the right end (100), with the
word "Anxious" printed above the line in the middle; the score is the number of millimeters
from the left end at which the participant made the mark. VAS measures have proven useful as
indicators of state anxiety in smoking research.
Demographics, smoking history, quitting history, and current (past month) smoking rate will
be measured with brief, face-valid questionnaires. The investigators have used in previous
studies a 10-item measure of current smoking rate, years of smoking, and length of longest
and most recent attempts to quit smoking. This measure is similar to, but a bit more detailed
than, the Active Smoking Questionnaire downloadable from the NCI website. It will be adapted
for this study to assess e-cigarette use, which is rapidly increasing, with at least
one-third of US adult smokers having ever used e-cigarettes.
Nicotine dependence will be indexed by the Fagerstrom Test of Nicotine Dependence (FTND17), a
6-item scale with moderate internal consistency and predictive validity in relation to
abstinence in studies of varenicline.
Visualization ability will be measured with the revised Vividness of Visual Imagery
Questionnaire (VVIQ2). Respondents are asked to form images of specific scenes and rate their
vividness. Validity data are favorable. For example, high scorers are more likely to notice
changes made to pictures they are shown.
Sensation seeking will be measured with the revised Sensation Seeking Scale-V. This
forced-choice self-report measure shows high internal consistency and extensive evidence of
concurrent validity in relating to attitudinal and behavioral criteria theoretically
associated with sensation seeking.
Contemplation of quitting will be measured in two ways. The Contemplation Ladder (CL)
consists of a ladder with rungs labeled 1 to 10. The lowest score (0, below the bottom rung)
represents "no thought of quitting", whereas the highest score (10) reflects "taking action
to quit (e.g., cutting down, enrolling in a program)". In a national population-based study
of smokers not initially interested in quitting immediately, CL scores predicted making a
quit attempt in response to an intervention. Also, self-reports will be used to stage smokers
according to an algorithm (no intention to quit within next six months = precontemplators;
intending to quit in next six months but not next 30 days = contemplators; intending to quit
in next 30 days = preparers).
Self-efficacy will be measured with the Smoking Self-Efficacy Questionnaire (SSEQ), a 17-item
self-report measure of confidence in one's ability to resist temptation to smoke in various
high-risk situations. SSEQ scores have been shown to predict length of time to first relapse
after a smoking cessation attempt.
Outcome expectancies for smoking will be measured in two ways. First, on the premise that
highly accessible expectancies regarding smoking may be the most influential in determining
smoking-related behavior, the "Self-Generated Outcome (SGO)" test calls for completion of the
stem "When I smoke cigarettes, I expect to …..", and coding is based solely on the first
response. Scores are sensitive to current mood and to smoking status. Second, the Smoking
Consequences Questionnaire-Adult (SCQ-A) is a well-validated 55-item self-report measure of
expected consequences of cigarette smoking.
Experimental manipulation of looming vulnerability. After completing baseline measures,
participants will be randomly assigned to either the looming condition or the control
condition (using a pre-selected random order generated via www.randomizer.org, with the
condition unknown to the experimenter until this point).
The randomization will be stratified by sex and by whether the participant had ever made an
attempt to quit smoking previously.
The imagery scenarios in each of the conditions (looming or control) will be the ones used in
McDonald et al. presented in one of four random orders.
Posttest measures: manipulation check and hypothesized mediator: After the imagery exercises,
participants will complete a second state anxiety VAS as an immediate manipulation check,
along with a rating of the vividness of the imagery. They will then complete the CSCLS-P (see
description and validity evidence in preliminary studies section above) to measure their
perception of the physical health consequences of smoking as looming threats. This measure
will be tested as a hypothesized mediator of the effects of the imagery induction on quit
attempts.
Advice to quit. At the completion of the assessments, the experimenter will give the
participant (regardless of experimental condition) a handout containing brief advice to quit
smoking, along with written information about (a) quitnet.com as a free site they could use
to obtain community support and extensive information concerning nicotine replacement
therapy, medications, behavioral methods for coping with high-risk situations, preparation
for quit date, and more, as well as (b) the telephone-based counseling provided for free via
1-800-QUIT-NOW.
Four-week follow-up assessment. Four weeks later there will be a second session, at which
participants will complete the CL and algorithm measures as indicators of contemplation
status as well as expectancy measures. Participants will also report on smoking rates and
quit attempts since the first experimental session. Quit attempts are the primary outcome,
but the investigators also consider changes in smoking rate meaningful. If participants claim
to have made a quit attempt, they will be asked for the duration of the attempt and whether
it is still in effect (i.e., whether they are currently abstinent, including no e-cigarette
use given that the health implications of switching to e-cigarette use remain uncertain.
Participants will complete an expired air CO test, and abstinence will be considered
corroborated by a reading of < 8 ppm.
To minimize demand effects, the four-week follow-up session will always be conducted by a
research assistant who (a) did not conduct time 1 assessments and (b) is masked to the
experimental condition of the participant.
The protocol at follow-up will be as follows:
1. Interview regarding any quit attempts of at least 24 hours since the lab experiment. If
there have been one or more such attempts, details will be sought concerning how long
the attempt lasted, whether it is ongoing, and what methods were used. The remaining
measures will be retests from baseline:
2. Current smoking rate.
3. Nicotine dependence.
4. Expired air CO reading.
5. Contemplation of quitting smoking.
6. Self-efficacy
7. Outcome expectancies.
