This trial has two levels of randomisation: first into the provision of structured planning tools (YES/NO), and then among that proportion of the sample who have not committed to an imminent attempt or already quit, randomisation into encouragement to quit as soon as possible (YES/NO) (see Table 1).
Eligibility for the Immediate arm is limited to those without a fixed quit date, or with a quit date two or more days away. The Structured Planning arm is open to all current smokers regardless of quit date, and also includes those quit for less than 4 days. The 2 × 2 design allows a test for interaction effects between the two aspects of each arm. The addition of the two supplementary conditions allows for a randomised test of the utility of structured planning on a broader sample, and non-randomised comparisons of the differential success rate of the QuitCoach as a function of participants’ progress toward quitting at recruitment (no quit date, quit dates of various times in the future, or already quit).
Participant recruitment
Participants will be recruited from QuitCoach users. Eligibility will be limited to those who are over 18 years of age, who reside in Australia, do not report a condition that would require referral to an in-person service (i.e. medicated for a mental health condition), and are interested in quitting smoking. For the Immediate arm it excludes those committed to an attempt within the next 2 days, but these are included along with those quit for up to 3 days in the Structured Planning arm. Interest in quitting is assessed by: “Which of the following best describes your current thinking about quitting? (a) I am planning to quit; (b) I am just open to the possibility (both eligible); (c) I am not interested in quitting in the near future (not eligible)”. QuitCoach users who do not consent to participate in the research receive the standard program.
Following the questions to establish eligibility (all part of the standard QuitCoach assessment), eligible participants are invited into a study “to find out whether the way people use the QuitCoach affects their chances of successfully quitting”. They are also told the study involves completing two short follow-up surveys, and that they might get access to some added functionality of the QuitCoach which are not yet available to everybody. They are also told: “We ask you to consider whatever recommendation the QuitCoach makes carefully and to follow the advice, unless you have good reasons not to.” Those consenting are sent an email welcoming them to the study and the brief research description.
We will use anonymous group data to assess whether those who agree to participate in the research differ from other users of the QuitCoach who meet the eligibility criteria.
Randomisation and allocation concealment
Randomisation is via a hidden binary number generator in the on-line recruitment survey which is activated after the person consents, allocating a code of 0 or 1 for each arm of the study (i.e., 0,0 = neither immediate implementation nor structured planning; 0,1 = no immediate implementation, receiving structured planning; 1,0 = receiving recommendation to quit immediately but no structured planning; 1,1 = receiving both interventions). Participants know what they are receiving (as blinding of participants is impossible in trials of behavioural interventions), but they are not told about the alternative arms, so are blind to differences between what they and others are receiving.
Interventions
Base condition This is the standard QuitCoach (the CC arm in Table 1). The QuitCoach consists of an assessment phase where users are asked a range of questions tailored to their progress towards quitting. No advice is provided during the assessment, except to a subgroup not eligible for this trial who report a mental health condition for which they are taking medication, who are recommended early in the assessment to seek medical advice in conjunction with use. On completion of the assessment users are provided with a tailored letter that provides a mix of personalised advice and encouragement tailored to their quit progress, level of addiction, self-efficacy, smoking-related beliefs, social supports, base levels of positive and negative affect, and identified challenges in dealing with temptations to smoke. Users are encouraged to quit when they are ready. The advice provides suggestions about the use of planning strategies, but they are not particularly highlighted, nor is any direction as to how to implement them provided in the letter. Third, there is provision of a range of untailored resources, which the tailored letter refers to where relevant, and those referred to are highlighted as being of potential use. Users are encouraged to use the program multiple times, and on second and subsequent times, feedback is provided not only on reported states at that time, but on progress from the previous assessment. Email reminders are sent to encourage return. Based on the evaluation of an earlier version of the program, only around one quarter (27%) return for a second assessment [25], even though multiple visits is associated with better outcomes [27].
More information about QuitCoach is available in the supplementary materials accompanying Borland, Balmford and Benda [28]. Readers who would like to see how the QuitCoach differs for each study condition can do so at http://historical.quitcoach.org.au (instructions for accessing the content of each condition are provided on the site).
The immediate implementation arm (IC and IP groups) This involves a modified version of the standard QuitCoach with key elements of the intervention delivered during the assessment stage. Those in this arm are encouraged (recommended) to quit immediately, or as soon as practically possible, during their initial QuitCoach assessment (and any subsequent assessments, if they have not already quit) (‘We suggest you think about setting a quit date right now. There is nothing to be gained by delaying it’). They are provided with a brief explanation of the reasons for doing so: that some recent research suggests that quitting as soon as you decide may increase the likelihood of success over delaying implementation. Those who have already set a quit date are encouraged to bring their quit date forward (‘We suggest you bring your quit date forward, as there is nothing to be gained by delaying it. Choose the earliest time you can’), ideally quitting immediately, later today or first thing tomorrow morning. Others are encouraged to take the next step toward quitting as soon as possible (e.g. for those planning to take prescription medication ‘We recommend you call the doctor to make an appointment immediately’), implement their quit attempt immediately they have done all they need to do, and to do this preliminary work in as short a period as possible (e.g. for those planning to cut down, ‘if you want to cut down, take no more than 4 more days to quit completely’). This is all done during the assessment phase. In addition, any commitment to immediate implementation is reinforced in the advice letter, and for those not taking up the suggestion during the assessment, they are encouraged to implement as soon as they feel ready to commit.
The structured planning intervention The structured planning augmentation of the QuitCoach (the IP, CP and XP arms of the study) consists of additional highly prescriptive instructions for planning a quit attempt, organised around two main tools; a To Do List (TDL) and a Problem Planner (PP). The To Do List operates something like the Task function in some computer diaries. It prompts the user by listing the most important things they need to do to increase their chances of quitting smoking successfully, with an indication of when they need to be done. The Problem Planner provides a template for the development of implementation intentions to survive identified problem situations.
Figure 1 shows a screenshot of the TDL for a study participant, displayed upon their return to the QuitCoach. The content of the TDL is dynamic, based primarily on smoking status/intention to quit, but also on other responses to the QuitCoach assessment including static variables such as age and gender, as well as things like levels of temptations and urges to smoke.
A maximum of 3 tasks are displayed on an individual’s TDL at any one time, with the list tailored both in terms of the tasks that appear on it, and the order in which they appear. The limit is to prevent the task seeming too overwhelming, and to maximise the completion of the tasks we consider most likely to be helpful. Each task is accompanied by a priority rating (highest, high or medium). Tasks potentially listed for inclusion on the TDL include: (a) finding out more about the health effects of smoking; (a) making or reviewing a list of your reasons for quitting; (b) deciding on a plan for how to quit, e.g. cold turkey or by systematically reducing consumption; (c) deciding on and, if relevant, implementing a plan for use of medication; (d) developing and documenting both cognitive and behavioural plans for coping in high-risk situations, using the Problem Planner; (e) making plans to ensure that friends and family are on-side to provide social support; (f) planning a schedule of rewards for achieving abstinence goals; (g) making your home smoke-free; (h) writing a list of things you will miss when you quit, and considering how these things can be achieved in other ways; (i) learning simple stress management techniques; (j) reviewing what went wrong on the previous quit attempt; (k) creating a smoking diary to better understand your smoking, and (l) if quit, spending a few minutes preparing for the day ahead. Many of these tasks refer participants to resources available on the QuitCoach site. These resources are available to all QuitCoach users, but only those in the structured planning arm will be directed to them in a systematic way. Participants may also add their own tasks to their TDL, but these do not displace existing tasks on the list.
Participants are encouraged to form implementation intentions for each listed task to help ensure each behavioural proscription or self-identified strategy for dealing with tempting situations is carried out. The instruction to do so is worded: ‘In the box below, write when you will do this, and anything else you want to add that will help you’. Tasks on the TDL are able to be marked as completed (at which point they are removed from the list and added to a ‘completed tasks’ list) or if the person decides not to do it, rejected (and added to a ‘rejected tasks’ list). Tasks marked as completed or rejected are replaced on the TDL by the next-highest priority task, if one exists.
The Problem Planner (PP) is a dynamically-generated form, presented in the form of a ‘wizard’ across several screens, into which participants can enter strategies for dealing with the situational temptations to smoke they identified during the QuitCoach assessment as likely to be difficult for them. For each identified strategy, participants are encouraged to form an implementation intention to help ensure that the strategy is remembered and implemented when needed (for example, ‘If I am at the pub and my friends go outside to smoke, then I will stay indoors and think about how much better it is not to smell of secondhand smoke). The PP wizard is structured into seven categories of tempting situations, of which five are presented to any one user. Three of them are mandatory (dealing with crises, strategies for slipups and other situations (those not covered earlier)). Two are chosen from the other four (coping with stress, social situations, first cigarette of the day, and filling in time), based on responses to the QuitCoach assessment. Under each category of situation, participants can create as many ‘if-then’ statements as they wish. Upon completion of the wizard, the PP is compiled into a form that can be viewed on screen and printed as a PDF document. On subsequent visits to the site this form can be edited, should the participant wish to add or delete problem statements. The planning intervention is designed to support those receiving it, and thus we would expect those users to return more often to the QuitCoach than other participants, although nothing mandates this.
Integration of the two interventions (IP group) Because the Structured Planning intervention is tailored to any level of immediacy in quitting, there is nothing unique about this group except that more will be doing their planning after the initiation of their quit attempt and more after full implementation (as will the XP group).
Common elements Frequency of use of the QuitCoach is at the participant’s discretion, regardless of which of the four possible study arms they have been randomised to. Thus, there is no set endpoint for delivery of the intervention. All participants will be reminded to return to the site via emails sent periodically over several weeks, scheduled according to their readiness to quit.
Assessment tools
We collect research information at three points: 1) at baseline, incorporated into the QuitCoach assessment (nearly all questions used are part of the standard assessment); 2) a first follow-up two weeks after the estimated quit date for each participant, or where the quit date is unknown or a quit date has not been set, a month after recruitment; and 3) A final follow-up 6 months after the identified quit date for each participant, or a comparable time after recruitment if no quit attempt was reported at the initial follow-up. Follow-up assessments will be conducted over the Internet, using email invitations including a web link to prime respondents to do the surveys online, or for those failing to respond to this, by telephone interview (the emailed invitation includes a notification that those failing to respond will be called).
The QuitCoach assessment, used as the baseline survey, includes validated measures of sociodemographics, quitting history, intention to quit [29], self-efficacy to quit [29], nicotine dependence [30], pros and cons of smoking and temptations to smoke [31], determination to quit [32] and a 5-item measure of positive and negative affect. All of these are used in the advice tailoring algorithms. To this we have added measures of rated quality of life, health status, perceived usefulness of planning, and the extent to which planning has already taken place on the current quit attempt (prior to recruitment). The base assessment will also ask for residential details (i.e., postcode) with which to determine socio-economic status as measured by SEIFA levels of area disadvantage [33].
At the first follow-up, we will assess smoking status, including implementation of the suggested quit date and actual quit date. We will ask about the extent of any planning undertaken since the baseline survey both pre- and post-full implementation of quit attempts (as relevant). We will measure use of other cessation support and use of pharmacotherapy (both pre-and post-implementation). The questions on affect will be re-asked in order to assess stability of mood. Finally, among those quit, we will measure self-efficacy to stay quit, extent of cravings [34], and determination to stay quit [32].
The final (6-month) follow-up will be restricted to measuring outcomes; smoking status, duration of time quit, and any lapses.
Engagement with the intervention will also be measured using naturally collected unobtrusive objective measures of program use [35], using web server log files and session identifiers linked to individual login names. Data collected will include the number of QuitCoach assessments completed and partially completed, number of log-ins to the site, number of openings of the advice page, To Do List and Problem Planner, number of edits of the To Do List, and number of times the additional resources page is viewed.
Sample size calculation
As noted earlier, we expect that a minority of participants will not comply with the recommendations to which they had been randomised. Based on levels of intervention usage achieved in a previous study in which participants were offered use of QuitCoach, a text messaging program or a combination [36], we anticipate at least 50% of those offered a program of structured planning will undertake a criterion level of planning (defined as one or more of seeking social support, practicing replacement strategies, or forming plans for coping with challenges, as reported at the first follow-up), whereas less than 5% of those in the IC and CC conditions will do so. We expect around 60% acceptance of the immediate implementation recommendation. This effectively means that the real effect of the intervention will be around twice the observed difference, which must be taken into account in power calculations.
We consider a 5% difference in absolute success rates (6 month sustained abstinence) to be highly significant. The expected base cessation rate for the control group (CC) is 18%, based on a comparable group from [28]. We propose a sample size of 600 per group (1200 per main effect comparison), which will provide 86% power to find a 5% increase in the success rate (23%) in the IC and CP conditions. We will have 98% power to find a 10% increase in the success rate (28%) in the IP condition over the CC condition, assuming no interaction. We have 80% power to find a difference of 6.6% between the IP and CC conditions [37]. A total sample size of 2400 across the 6 groups (i.e., with 800 per main effect comparison, with 800 in the XP and XC conditions combined) provides 68% power to find a 5% increase in the success rate in the IC and CP conditions.
Outcomes and data analysis
The primary outcome measure will be the percentage of smokers reporting 6-month sustained abstinence at the final follow-up, with supplementary analyses of the percent making a quit attempt assessed at 2-week post-implementation date, and point-prevalence abstinence at each follow-up point. The primary analyses will use intention to treat analysis with various strategies for dealing with missing data (all will be followed up regardless of engagement with the interventions). Some analyses will be conducted using only reported outcomes, especially those that involve possible mediators or moderators of effect, which will include logistic regressions. Biochemical validation of cessation outcome is considered unnecessary in larger population-based studies (particularly where there are low demands on the participants and no face-to-face therapist contact) as levels of misrepresentation are generally low and unsystematic [38]. This is an effectiveness trial where randomisation is to a set of recommendations which we know a significant proportion of participants will not follow. We will monitor both the choices smokers make around timing of implementation and the extent to which they comply with exercises and advice around structured planning as these should mediate outcomes see [39]. In doing so we will ask about any pre-decisional planning and prior quit experience. Nonetheless, the primary analysis will explore condition by outcome, independent of intervention compliance. Important secondary outcomes are whether the proportion of smokers who accept the offer to schedule their quit attempt and/or implement criterion levels of planning differs by condition, and the prospective relationship between those actions and success. We will also assess the impacts of the interventions and the outcomes on measures of quality of life, affect (particularly signs of depression), and overall health. This will be done both as a function of allocated condition and by achieved outcome.
Ethical review
The study protocol was approved by the Cancer Council Victoria Human Research Ethics Committee (HREC No. 1108).