This protocol (date: 20 December 2018) is original. The study will be completed within 18 months (from 1st June 2019 to 30th November 2020). A randomised controlled trial, with two-group pre-test and repeated post-test, between subjects design will be adopted following CONSORT statements (Fig. 1).
Hong Kong Chinese smokers with chronic diseases who have medical follow-up in a SOPC and fulfil the following inclusion criteria will be invited to participate: (1) aged 18 years or above, (2) able to speak Cantonese and read Chinese, (3) no intention to quit smoking (pre-contemplation stage), but are willing to take action to promote health, (4) have a smart phone and able to use instant messaging tool (e.g. WhatsApp, WeChat) for communication, and (5) willing to receive health promotion advices via WhatsApp/WeChat in the smart phone throughout the study. The exclusion criteria are: (1) unable to give informed consent or participate in our intervention due to impaired mental status, cognitive impairment, or communication barrier, and (2) participation in other smoking cessation programmes or services.
Randomisation and blinding
The method of simple complete randomisation will be adopted. The subjects will be randomly allocated into one of the two groups: the control group or the intervention group. The randomisation will be performed by a research assistant who will open a serially numbered, opaque and sealed envelope (SNOSE) with a card inside indicating the randomly allocated group. The random numbers used for group assignment will be generated using a personal computer by another research assistant who does not involve in subject recruitment. Since the intervention is not a usual practice in the SOPC, we cannot completely blind the subjects. However, a single-blind approach will be adopted, with all outcome assessors and data analysts will be blinded to the group assignment.
Sample size calculation
To determine the efficacy of using a personalized general health promotion approach in promoting smoking cessation for smokers with chronic diseases, we will recruit 60 smokers (30 in the intervention and 30 in the control groups) having medical follow-up in a SOPC in this study.
Power analysis will not be adopted for calculating the sample size as we have found no similar intervention in the literature. However, with the available resources and the proposed timeframe, we will be able to recruit 60 subjects. We therefore propose to have the sample size of 60 for this study, with 30 in the experimental group and 30 in the control group.
After completing the baseline questionnaires, the trained research assistant will first ask the subjects about the priority of engaging in any desirable health-related lifestyle practice as identified in the completed baseline questionnaires (i.e. smoking reduction or quitting, regular physical activity, healthy diet and reduce alcohol consumption). The subjects will also ask to state a targeted goal in which they perceive as the easiest to achieve, such as eating more vegetables, eating less salted or fried food, engaging in more or higher intensity of exercise, reducing alcohol consumption, reducing number of cigarette consumption per day or quitting. Each subject will then receive an individual face-to-face brief MI (about 5 min) with generic health advice on selected health-related lifestyle practice. All subjects will then be informed that they will receive an individual brief MI intervention to assist behavioural changes or achieve goals as desired or chosen by them via WeChat or WhatsApp in the smart phones throughout the study period. In addition, the subjects will be given a self-help smoking cessation booklet with a public quitline number.
Follow-up booster intervention
The trained research assistant will deliver brief MI to each subject in the intervention group individually via WeChat or WhatsApp in the smart phones throughout the study period. The brief MI messages will be delivered more intensively as preferred by the subject (usually not less than once per 2–3 days and no more than 2 times per day) for the first 6 months. The frequency of delivering message through WeChat or WhatsApp will be interactive, depended on subjects’ actions and responses. It may take several sessions of chats within several days/weeks. However, the total time spent by the research assistant would not be more than that for traditional MI with several long sessions.
Start from 6 months, minimal messages by merely following the subjects’ progress and responding to their questions to maintain contact will be provided to subjects till one-year follow-up.
Content of the brief MI messages
The content of the brief MI messages will depend on the desirable health-related lifestyle practice and the targeted goal in which the subjects perceive as the easiest to achieve. The trained research assistant will give brief MI messages with an aim at moving the subjects towards the goal. The brief MI messages will be guided by the menu of strategies (Table 1). As the trained research assistant moves down the menu, greater readiness to change from the subjects will be required. During the process of delivering brief MI via WeChat or WhatsApp, the trained research assistant will follow the menu of strategies and start from the top. To begin the conversation, the trained research assistant will first explore the subjects’ current barriers and facilitators, and lifestyles by asking, ‘What are your current lifestyle practice in general?’, and ‘What are your current barriers and facilitators?’ The trained research assistant will then raise the topic of not engaging in desirable health-related lifestyle practice with open-ended question such as ‘How does your current lifestyle practice fit in? ‘How does your current lifestyle practice affect your health?’ After that, the trained research assistant will ask the subjects to describe a typical day with how the current lifestyle practice fit in. In this strategy, it is important to train the research assistant to be aware not to push the subjects nor to insert their own hypothesis into the conversation. The trained research assistant will then bring the pros and cons of the subjects’ current lifestyle practice by questions such as ‘What are some of the good things/less good things of your current lifestyle practice?’. When the subjects become curious about the current or the desirable health-related lifestyle practice, the trained research assistant will ask for permission before providing relevant information by questioning ‘I wonder if you would be interested in knowing … ’. The trained research assistant will elicit a discrepancy by asking an open-ended question such as ‘How would you like things to be in the future?’. To explore the concerns, the trained research assistant will raise questions, ‘What concerns do you have about engaging in desirable health-related lifestyle practice?’ and ‘What other concerns do you have now?’. When the concerns are clearly manifest, an open question like, ‘What does this leave you now?’ can help subjects to decide the future actions. The research assistant will be trained to summarize subjects’ statements constantly throughout the conversation.
Also, the technique of expressing empathy will be incorporated in the intervention so as to develop a genuine and closer relationship of caring with the subjects. Expressing empathy is a specifiable and learnable skill for understanding another’s meaning through the use of reflective listening . To incorporate such skill into the intervention, the trained research assistant will be reminded to show respect in the messages, especially not to impose direction and judgment regarding the subjects’ decision. Also, throughout the conversations, the attitude of the research assistant should be acceptance, but not necessarily approval or agreement. Besides, the research assistant will be reminded that ambivalence is normal and they should avoid forcing the subjects to change .
Assessment for readiness to quit at 3-month follow-up
Although subjects do not have an intention to quit smoking at baseline (one of the inclusion criteria), the readiness of quitting smoking will be assessed at 3-month follow-up. For those who are willing to take further actions to promote their health, i.e. with an intention to quit smoking, health advice on smoking will be given with more emphasis on the health benefits of quitting. Upon request by subjects, we shall provide them with more comprehensive information on quitting. Specifically, the intervention should address the needs of smoking patients by teaching them with the skills to overcome withdrawal symptoms or cigarette cravings. In addition, subjects will be allowed to select their own schedules of quitting, such as to quit immediately or progressively. Our previous randomised controlled trial on the effectiveness of a self-determination intervention for smoking cessation (immediate or progressive) among people attending emergency departments showed that by giving autonomy for smokers to select their own schedules of quitting would enhance their self-efficacy and competence in quitting smoking. For those who request nicotine replacement therapy (NRT) to assist them quitting, we shall refer them to a smoking cessation hotline in which free sample of NRT will be offered. The whole intervention will be given to the subjects through WeChat/WhatsApp during the process of the study. However, we understand that older people always appreciate regular phone conversations intermingled with message. Hence, there will be a follow-up telephone call with our subjects each month for the first 6 months so as to further build a closer relationship with them.
A registered nurse with more than 5 year of experience in delivering smoking cessation interventions will be employed as the research assistant for this study. This registered nurse has already trained to use brief MI to provide face-to-face smoking cessation advices. However, to ensure that she will fully comply with our protocol, a half day training workshop by the research committee (principal and co-investigators) will be offered to her before this study. The workshop will include the principles and practices on brief MI and healthy lifestyles. The skills of brief MI will be co-learnt between the registered nurse and the principal and co-investigators through demonstrations and return demonstrations. Significantly, case study examples will be thoroughly discussed via role playing to permit the registered nurse to understand and practise the required skills. To ensure the quality and competence of the registered nurse in applying the learnt skills before implementation, she will be needed to complete an assessment with a case study examination after the workshop. The assessment will be performed by one of the research committee members who has expertise in using brief MI.
Similar to the intervention group, the trained research assistant will first ask the subjects about the priority of engaging in any desirable health-related lifestyle practice and to state a targeted goal in which they perceive as the easiest to achieve after completing the baseline questionnaires. In addition, the subjects will be given a self-help smoking cessation booklet with a public quitline number. However, subjects in the control group will not receive brief MI and follow-up booster intervention.
Before randomisation, the subjects will be invited to complete a structured questionnaire, administered by a trained research assistant face-to-face. This structured questionnaire will be developed through adopting or modifying international and/or locally validated instruments. The questionnaire will gather information including smoking and quitting history, stage of readiness to quit, utilization of existing smoking cessation services, and demographic information such as age, gender, and marital status. The clinical information will be obtained by the trained research assistant from the subjects’ medical records.
All subjects will receive follow-up telephone call at 1, 3, 6 and 12 months from our trained research assistant. In each telephone follow-up, the subjects will be asked to complete the structured questionnaire again. Subjects who are abstinent from cigarette use ≥7 days at 12-month follow-up will be invited for a biochemical validation. The biochemically validated 7-day point prevalence of abstinence will be confirmed by saliva cotinine level < 115 ng/ml in parallel test and a carbon monoxide level in expired air < 9 ppm (p.p.m.) . These biochemical validation methods have been used in previous studies on smoking cessation [19, 20]. For subjects on nicotine replacement therapy, biochemical validation will be conducted 7 days after the completion of therapy.
The primary outcome is biochemically validated smoking abstinence at 12 months.
Secondary outcomes are: (i) self-reported 7-day point prevalence of smoking abstinence at 6 and 12 months, (ii) self-reported reduction of ≥50% in cigarette consumption at 6 and 12 months, and (iii) any behaviour change as indicated by the subjects.
The SPSS for Windows (version 25) will be used to conduct data analysis. We will first compare the baseline characteristics of the 2 groups using chi-square test for categorical variables and student t-test or Wilcoxon rank-sum test for continuous variables. The primary analysis will be the effect size of the intervention at 12 months. It will be estimated by the odd ratios (ORs). Crude ORs for quitting at 12 months will be estimated using logistic regression model and compared with ORs adjusted for potential or confirmed confounding baseline variables. The difference in biochemical validation quit rates at 12-month follow-up between intervention and control groups will be determined using Pearson’s chi-square test or with the use of Fisher’s exact test. Independent samples t-test will be used to determine whether there are statistically significant differences in length of abstinence for quitter between the intervention and control groups at 6 and 12-month follow-ups. The approach of intention-to-treat will be adopted. 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 sensitivity analyses. Also, the number of communications with the subjects using WhatsApp/WeChat will be documented and analysed. In particular, all posts in the WhatsApp/WeChat will be archived. Each post will then be coded by 2 researchers independently, and will be classified by their content. Mann-Whitney U test will be applied to compare the median number of posts between the experimental and control group.
This study was approved by the institutional Review Board of the Hospital Authority of New Territories West Cluster (reference: NTWC/REC/19001), and was registered on the ClinicalTrials.gov (reference: NCT03983330). During subject recruitment, all eligible smokers who are willing to participate will be briefed on the purpose, design, procedures, potential benefits and risks of the study. Written consent will then be obtained.
Patient and public involvement
Patients and public will not be included in the development, design, implementation or dissemination of the research. The results will be disseminated to the subjects through patient forums.