Preference of young adults for COVID-19 vaccination in the United Kingdom: a discrete choice experiment.

OBJECTIVES: To determine preferences for COVID-19 vaccinations in the young adult population in the United Kingdom (UK). METHOD: A discrete choice experiment survey was conducted in UK young adults. Participants were asked to choose between two hypothetical vaccines the one they preferred the most. Vaccines were defined by five attributes (effectiveness, risk of side effects, duration of protection, number of doses, confidence in available evidence), identified following a systematic literature review and qualitative interviews with 13 young adults. A random parameters logit model, a latent class model, and subgroup analyses were used to identify preferences. RESULTS: One hundred and forty-nine respondents were included (70% women, mean age 23 years). All five attributes significantly influenced respondents' vaccination decisions. Respondents valued higher effectiveness, lower risk of side effects, longer protection duration, and a smaller number of doses. Based on the range of levels of each attribute, vaccine effectiveness was the most important attribute (relative importance 34%), followed by risk of side effects (32%), and duration of vaccine protection (22%). CONCLUSIONS: The five investigated vaccine attributes appear to play an important role in young adults' decision-making process. Results of this study may help health authorities designing appropriate strategies in future vaccines campaigns in the younger UK population.

Beliefs regarding COVID-19 vaccinations of young adults in the United Kingdom: An interview study applying the Integrated Change Model.

INTRODUCTION: Young adults are considered one of the most hesitant groups towards getting vaccinated in the UK, which threatens the success of the vaccination program in ending the pandemic. Identifying and understanding the socio-cognitive beliefs is important to effectively design and implement health communication interventions. Therefore, the aim of this study was to identify the underlying beliefs regarding COVID-19 vaccinations among young adults in the UK. METHODS: The study consisted of online, one-on-one interviews with 18 individuals (6 males, 12 females) aged between 18 and 29 years, conducted in June 2021. The guiding theoretical framework was the I-Change Model. Interviews were recorded and transcribed verbatim. The transcripts were independently coded by two researchers by using the constructs of the I-Change Model. Belief statements were elicited from the codes and the frequency of belief statements was recorded and compared between intenders and non-intenders. RESULTS: Similar beliefs were observed in intenders and non-intenders for most constructs of the I-Change Model. However, non-intenders distinguished themselves from intenders by their higher perceived risks of side effects and higher perceived disadvantages of being vaccinated. Non-intenders expressed the belief that the risk of unknown or long-term side effects, such as blood clotting and impact on fertility, were the main reason for them not to be willing to vaccinate. In addition, in both groups, participants had mostly similar beliefs as their friends and family. CONCLUSION: This research provides insights in the specific beliefs of the young adult population of the UK regarding COVID-19 vaccinations, which could have implications for health communication interventions. The findings suggest that such interventions should focus on reducing the uncertainty regarding short- and long-term effects and potentially having a focus on the entire social environment of young adults.

Disentangling interventions to reduce fear of falling in community-dwelling older people: a systematic review and meta-analysis of intervention components.

PURPOSE: Fear of falling (FoF) is a common and debilitating problem for older people. Most multicomponent interventions show only moderate effects. Exploring the effective components may help in the optimization of treatments for FoF. MATERIALS AND METHODS: In a systematic review of five scientific literature databases, we identified randomized controlled trials with older community-dwelling people that included FoF as an outcome. There was no restriction on types of interventions. Two reviewers extracted information about outcomes and content of interventions. Intervention content was coded with a coding scheme of 68 intervention components. We compared all studies with a component to those without using univariate meta-regressions. RESULTS: Sixty-six studies, reporting on 85 interventions, were included in the systematic review. In the meta-regressions (n = 49), few components were associated with intervention effects at the first available follow up after the intervention, but interventions with meditation, holistic exercises (such as Tai Chi or Pilates) or body awareness were significantly more effective than interventions without these components. Interventions with self-monitoring, balance exercises, or tailoring were less effective compared to those without these components. CONCLUSIONS: The identified components may be important for the design and optimization of treatments to reduce FoF. Implications for rehabilitationFear of falling (FoF) is a common and debilitating issue among older people and multicomponent interventions usually show only small to moderate effects on FoF.This review and meta-analysis investigated 68 intervention components and their relation to intervention effects on FoF.Interventions with meditation, holistic exercises (such as Tai Chi), or body awareness are more effective than interventions without these components.Clinicians aiming to reduce FoF may recommend selected interventions to older people taking into account the current knowledge of intervention components.

The most important facilitators and barriers to the use of Health Technology Assessment in Canada: a best-worst scaling approach.

BACKGROUND: Health Technology Assessment (HTA), which can support public drug reimbursement decisions will play a core function in the planned national Pharmacare program in Canada. To address existing barriers to the use of HTA, these must be ranked in order of priority. The goal of this study was to access the relative importance of known facilitators and barriers to the use of HTA in the context of the Canadian health care system, with attention to differences between regions and stakeholder groups. METHODS: We used the best-worst scaling object case approach to elicit a quantitative ranking of a list of 20 facilitators and 22 barriers. A sample of 68 Canadian HTA stakeholders, including members of expert committees, decision/policymakers, researchers/academics, and others participated in the study. Their task was to identify the most important and the least important item in 12 sub-sets of five facilitators and 14 sub-sets of five barriers. FINDINGS: Relative Importance Scores derived via hierarchical Bayes analysis revealed relations, engagement, and contact between stakeholders as most important on both the barrier and facilitator sides. Other top-ranked facilitators included the availably of credible and relevant research. Other top-ranked barriers included inconsistencies in the evidence and limited generalizability. The availability of HTA guidelines did not rank highly on either side. The main limitation of the study was the challenge with reaching the relevant respondents; this was mitigated by involving the national HTA agency in the research. CONCLUSION: Canadian stakeholders consider the relationships within the HTA network among the most important. Policies should focus on strengthening these relationships. Future research should focus on the connectivity and distribution of knowledge and power within the HTA network.

Most Important Factors for Deciding Rehabilitation Provision for Severe Stroke Survivors Post Hospital Discharge: A Study Protocol for a Best-Worst Scaling Experiment.

Efficient decision-making is crucial to ensure adequate rehabilitation with optimal use of healthcare resources. Establishing the factors associated with making decisions concerning rehabilitation provision is important to guide clinical staff towards person-centred decisions for rehabilitation after severe stroke. In this study we conduct a best-worst scaling (BWS) experiment to identify the most important factors and their relative weight of importance for deciding the type of ongoing rehabilitation services a person with severe stroke might receive post hospital discharge. Fractional, efficient designs are applied regarding the survey design. Key multidisciplinary staff regularly involved in making decisions for rehabilitation in a stroke unit will be recruited to participate in an online BWS survey. Hierarchical Bayes estimation will be used as the main analysis method, with the best-worst count analysis as a secondary analysis. The survey is currently being piloted prior to commencing the process of data collection. Results are expected by the end of September 2021. The research will add to the current literature on clinical decision-making in stroke rehabilitation. Findings will quantify the preferences of factors among key multi-disciplinary clinicians working in stroke units in the UK, involved in decision-making concerning rehabilitation after stroke.

Knowledge and perceptions of Alzheimer's disease in three ethnic groups of younger adults in the United Kingdom.

BACKGROUND: Alzheimer's disease (AD) is a global public health problem with an ageing population. Knowledge is essential to promote early awareness, diagnosis and treatment of AD symptoms. AD knowledge is influenced by many cultural factors including cultural beliefs, attitudes and language barriers. This study aims: (1) to define AD knowledge level and perceptions amongst adults between 18 and 49 years of age in the UK; (2) to compare knowledge and perceptions of AD among three main ethnic groups (Asian, Blacks, and Whites); and (3) to assess potential associations of age, gender, education level, affinity with older people (65 or over), family history and caregiving history with AD knowledge. METHODS: Data was collected from 186 participants as a convenience sample of younger adults of three different ethnicities (16.1% Asian, 16.7% Black, 67.2% White), living in the UK, recruited via an online research platform. The majority of the participants were in the 18-34 years age group (87.6%). Demographic characteristics of participants and AD knowledge correlation were assessed by the 30-item Alzheimer's Disease Knowledge Scale (ADKS), comprising 7 content domains. ANOVA/ANCOVA were used to assess differences in AD knowledge by ethnicity, gender, education level, age and affinity with dementia and Alzheimer's patients. RESULTS: For AD general knowledge across all respondents only 45.0% answers were correct. No significant differences were found for the total ADKS score between ethnicities in this younger age group, who did not differ in education level. However, there were significant knowledge differences for the ADKS symptom domain score even after controlling for other demographics variables such as gender, education level (p = 0.005). White respondents were more likely to know about AD symptoms than their Black counterparts (p = 0.026). CONCLUSION: The study's findings suggest that the AD knowledge level is not adequate for all ethnic groups. Meanwhile, significant differences were observed in symptoms, between ethnic groups, and therefore, differ in their needs regards health communication. The study contributes to an understanding of ethnicity differences in AD knowledge amongst adults from 18 to 49 years of age in the UK and may also provide input into an intervention plan for different ethnicities' information needs.

Knowledge, socio-cognitive perceptions and the practice of hand hygiene and social distancing during the COVID-19 pandemic: a cross-sectional study of UK university students.

BACKGROUND: During the first wave of the COVID-19 pandemic, social distancing and hand hygiene have been the primary means of reducing transmission in the absence of effective treatments or vaccines, but understanding of their determinants is limited. This study aimed to investigate knowledge and socio-cognitive perceptions, and their associations with such protective behaviours, in UK university students. METHODS: A cross-sectional online survey of 293 students was undertaken on 13 May 2020. Survey questions addressed demographics, knowledge of the disease and effectiveness of the protective measures, risk perception, socio-cognitive perceptions (e.g. attitude, social support, and self-efficacy), habit, time factors and trust, as well as the hand hygiene and social distancing behaviours. Multiple linear regression was used to identify the strongest associations of potential determinants with behaviour. RESULTS: Participants reported high levels of social distancing with 88.9% answering "Mostly" or "Always" for every activity, but only 42.0% reporting the same for all hand hygiene activities. Knowledge of the effectiveness of each activity in preventing transmission was high, with 90.7% and 93.5% respectively identifying at least 7 of 8 hand hygiene or 9 of 10 social distancing activities correctly. Habit (ß = 0.39, p = 0.001) and time factors (ß = 0.28, p = 0.001) were the greatest contributors to unique variance in hand hygiene behaviour, followed by ethnicity (ß = - 0.13, p = 0.014) and risk perception (ß = 0.13, p = 0.016). For social distancing behaviour, the determinants were self-efficacy (ß = 0.25, p < 0.001), perceived advantages (ß = 0.15, p = 0.022), trust in policy (ß = 0.14, p = 0.026) and gender (ß = - 0.14, p = 0.016). Regression models explained 40% hand hygiene and 25% social distancing variance. CONCLUSIONS: This study indicated that communications about effectiveness of hand hygiene and social distancing behaviours had been effective in terms of knowledge acquisition. However, in the light of likely second waves of COVID-19, attention to maintaining social distancing behaviour and improving hand hygiene behaviour may need to address more difficult areas of changing habits, overcoming time factors and building trust, as well as interventions to increase self-efficacy and address risk perception concerns.

Effects of the reform of the Dutch healthcare into managed competition: Results of a Delphi study among experts.

BACKGROUND: In 2006 a major healthcare reform was introduced in the Netherlands, implying managed competition. This study explored the level of consensus on the outcomes and desired changes of this new system, and differences between stakeholder groups. METHODS: A three-round Delphi-study was conducted among Dutch healthcare insurers, health economists, and professionals in general practice (GP) care and mental health (MH) care. In the first round, 20 experts indicated the most important advantages and disadvantages of the Dutch managed competition, and desired changes. Experts in the second (n = 106) and third round (N = 88) rated the importance of the 88 factors identified in the first round. RESULTS: Only healthcare insurers reached consensus on important advantages (i.e. improved efficiency; room for choice). Health economists reached almost no consensus on any factors. GP and MH-care professionals reached most consensus on disadvantages (i.e. focus on price over quality, increased bureaucracy) and desired changes (i.e. reduce bargaining power of healthcare insurers; increase attention for care of complex patients); half of them suggested abolishment of managed competition. CONCLUSION: GP and MH-care professionals were most dissatisfied and suggested several changes or even abolishment of the 2006 reform; healthcare insurers mentioned some benefits. This level of dissatisfaction among health care professionals indicates that there is room for improvement, preferably developed in conjunction with stakeholders.

Intervention Characteristics Associated With a Reduction in Fear of Falling Among Community-Dwelling Older People: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND AND OBJECTIVES: Fear of falling (FoF) is associated with decreased physical functioning and an increased fall risk. Interventions generally demonstrate moderate effects and optimized interventions are needed. Intervention characteristics, such as setting or delivery method may vary. We investigated which overarching intervention characteristics are associated with a reduction in FoF in community-dwelling older people. RESEARCH DESIGN AND METHODS: A systematic review and meta-analysis of randomized controlled trials (RCTs) in community-dwelling older people without specific diseases was performed. Associations between intervention characteristics and standardized mean differences (SMD) were determined by univariate meta-regression. Sensitivity analyses were performed. RESULTS: Data on 62 RCTs were extracted, 50 intervention groups were included in the meta-analysis. Most intervention characteristics and intervention types were not associated with the intervention effect. Supervision by a tai chi instructor (SMD: -1.047, 95% confidence interval [CI]: -1.598; -0.496) and delivery in a community setting (SMD: -0.528, 95% CI: -0.894; -0.161) were-compared to interventions without these characteristics-associated with a greater reduction in FoF. Holistic exercise, such as Pilates or yoga (SMD: -0.823, 95% CI: -1.255; -0.392), was also associated with a greater reduction in FoF. Delivery at home (SMD: 0.384, 95% CI: 0.002; 0.766) or with written materials (SMD: 0.452, 95% CI: 0.088; 0.815) and tailoring were less effective in reducing FoF (SMD: 0.687, 95% CI: 0.364; 1.011). DISCUSSION AND IMPLICATIONS: Holistic exercise, delivery with written materials, the setting and tailoring potentially represent characteristics to take into account when designing and improving interventions for FoF in community-dwelling older people. PROSPERO international prospective register of systematic reviews, registration ID CRD42018080483.

Combining the Integrated-Change Model with Self-Determination Theory: Application in Physical Activity.

Background: Critically testing and integrating theoretical models can aid health promotion research and intervention planning. This study aimed to critically compare and integrate Self-Determination Theory (SDT) and Integrated-Change Model (ICM) for explaining physical activity behaviour. Methods: A dataset was used with Dutch adults, consisting of information on demographics and socio-cognitive and behavioural determinants. There were three measurements over a period of six months, with the baseline sample consisting of 1867 participants. Confirmatory factor analysis was conducted to assess the reliability of the items and their corresponding scales. To examine cognitive pathways, we applied Structural Equation Modelling (SEM). Results: For SDT, none of the pathways were significant but the model fit was decent (R2 = 0.20; RMSEA = 0.07; CFI = 0.91). For ICM, the model fit was similar (R2 = 0.19; RMSEA = 0.07; CFI = 0.73), with many significant pathways, as stipulated by the theory. The integration of STD and ICM constructs revealed similar explained behavioural variance (R2 = 21%), with no significantly different model fit. Conclusion: The integration of SDT and ICM added no value as a prediction model. However, the integrated model explains the underlying mechanism of STD constructs, as well as the determinants of attitude, social influences, and self-efficacy. In the context of intervention design, ICM or the integrated model seem most useful as it reveals the stages and pathways to behaviour change.

Spoken Animated Self-Management Video Messages Aimed at Improving Physical Activity in People With Type 2 Diabetes: Development and Interview Study.

BACKGROUND: Web-based tailored interventions are a promising approach to help people with type 2 diabetes successfully adopt regular physical activity. Spoken animation seems to be effective regardless of the characteristics of the user and may be a relevant strategy to communicate complex health information. OBJECTIVE: The objectives of our study were to evaluate (1) pretesting communication elements and user appreciation, and (2) the applied behavior change techniques of the previously designed spoken animated video messages in a tailored self-management program for people with type 2 diabetes. METHODS: We conducted semistructured interviews with patients with type 2 diabetes recruited from general practices located in different socioeconomic status urban neighborhoods. Based on the pretesting key communication elements of Salazar's model, we asked participants about the spoken animated video messages' attractiveness, comprehensibility, acceptance, believability, involvement, and relevance and to what extent the video messages motivated them to become more physically active. We also assessed participants' intention to use the spoken animated video messages and to recommend them to others. To evaluate participants' appreciation of the different applied behavior change techniques, we conducted a post hoc analysis of the qualitative data using the MAXQDA program. Transcripts were coded by 2 coders using iterative qualitative content analysis methods to uncover key health communication issues. RESULTS: Of 23 patients who expressed an interest in participating, 17 met the inclusion criteria and 15 took part in the interviews. The positive appreciation of the comprehensibility, believability, and personalization was supported by participants' statements on behavior change techniques and other communication elements. Reinforcement of and feedback on participants' answers were positively evaluated as was the simplicity and concreteness of the spoken animated video messages. Most participants indicated reasons for not feeling motivated to increase their physical activity level, including being already sufficiently physically active and the presence of other impeding health factors. CONCLUSIONS: Spoken animated video messages should be simple, short, concrete, and without the use of medical terminology. Providing positive reinforcement, feedback on participants' answers, examples that match user characteristics, and the possibility to identify with the animation figures will enhance involvement in the health message. To connect more with patients' needs and thereby increase the perceived relevance of and motivation to use an animated video program, we suggest offering the program soon after diabetes mellitus is diagnosed. We recommend piloting behavior change techniques to identify potential resistance.

A discrete choice experiment to assess patients' preferences for HIV treatment in the rural population in Colombia.

Aim: To elicit patients' preferences for HIV treatment of the rural population in Colombia.Methods: A discrete choice experiment (DCE), conducted in a HIV clinic in Bogotá, was used to examine the trade-off between five HIV treatment attributes: effect on life expectancy, effect on physical activity, risk of moderate side-effects, accessibility to clinic, and economic costs to access controls. Attributes selection was based on literature review, expert consultation and a focus group with six patients. An efficient experimental design was used to define two versions of the questionnaire with each of 12 choice sets and a dominance task was added to check reliability. A mixed logit model was then used to analyse the data and sub-group analyses were conducted on the basis of age, gender, education, and sexual preference.Results: A total of 129 HIV patients were included for analysis. For all treatment attributes, significant differences between at least two levels were observed, meaning that all attributes were significant predictors of choice. Patients valued the effect on physical activity (conditional relative importance of 27.5%) and the effect on life expectancy (26.0%) the most. Sub-group analyses regard age and education showed significant differences: younger patients and high educated patients valued the effect on physical activity the most important, whereas older patients mostly valued the effect on life expectancy and low educated patients mostly valued the accessibility to clinic.Limitations: One potential limitation is selection bias, as only patients from one HIV clinic were reached. Additionally, questionnaires were partly administered in the waiting rooms, which potentially led to noise in the data.Conclusions: This study suggests that all HIV treatment characteristics included in this DCE were important and that HIV patients from rural Colombia valued short-term efficacy (i.e. effect on physical activity) and long-term efficacy (i.e. effect on life expectancy) the most.

A discrete choice experiment to assess patients' preferences for HIV treatment in the urban population in Colombia.

Aim: This study aimed to assess patients' preferences for HIV treatment in an urban Colombian population.Methods: A Discrete Choice Experiment (DCE) was conducted. Urban Colombian HIV patients were asked to repetitively choose between two hypothetical treatments that differ in regard to five attributes 'effect on life expectancy', 'effect on physical activity', 'risk of moderate side effects, 'accessibility to clinic' and 'economic cost to access controls'. Twelve choice sets were made using an efficient design. A Mixed Logit Panel Model was used for the analysis and subgroup analyses were performed according to age, gender, education level and sexual preference.Results: A total of 224 HIV patients were included. All attributes were significant, indicating that there were differences between at least two levels of each attribute. Patients preferred to be able to perform all physical activity without difficulty, to have large positive effects on life expectancy, to travel less than 2 h, to have lower risk of side-effects and to have subsidized travel costs. The attributes 'effect on physical activity' and 'effects on life expectancy' were deemed the most important. Sub-analyses showed that higher educated patients placed more importance on the large positive effects of HIV treatment, and a more negative preference for subsidized travel cost (5% level).Limitations: A potential limitation is selection bias as it is difficult to make a systematic urban/rural division of respondents. Additional, questionnaires were partly administered in the waiting rooms, which potentially led to some noise in the data.Conclusions: Findings suggests that short-term efficacy (i.e. effect on physical activity) and long-term efficacy (i.e. effect on life expectancy) are the most important treatment characteristics for HIV urban patients in Colombia. Preference data could provide relevant information for clinical and policy decision-making to optimize HIV care.

Examining the Factor Structure of the Pittsburgh Sleep Quality Index in a Multi-Ethnic Working Population in Singapore.

The Pittsburgh Sleep Quality Index (PSQI) is a widely used measure for assessing sleep impairment. Although it was developed as a unidimensional instrument, there is much debate that it contains multidimensional latent constructs. This study aims to investigate the dimensionality of the underlying factor structure of the PSQI in a multi-ethnic working population in Singapore. The PSQI was administered on three occasions (baseline, 3 months and 12 months) to full-time employees participating in a workplace cohort study. Exploratory factor analysis (EFA) investigated the latent factor structure of the scale at each timepoint. Confirmatory factor analysis (CFA) evaluated the model identified by EFA, and additionally evaluated it against a single factor and a three-factor model. The EFA identified a two-factor model with similar internal consistency and goodness-of-fit across each timepoint. In the CFA, the two- and three-factor models were both superior to the unidimensional model. The two- and three-factor models of the PSQI were reliable, consistent and provided similar goodness-of-fit over time, and both models were superior to the unidimensional measure. We recommend using the two-factor model to assess sleep characteristics in working populations in Singapore, given that it performs as well as the three-factor model and is simpler compared to the latter.

Health Effects of Underground Workspaces cohort: study design and baseline characteristics.

The development of underground workspaces is a strategic effort towards healthy urban growth in cities with ever-increasing land scarcity. Despite the growth in underground workspaces, there is limited information regarding the impact of this environment on workers' health. The Health Effects of Underground Workspaces (HEUW) study is a cohort study that was set up to examine the health effects of working in underground workspaces. In this paper, we describe the rationale for the study, study design, data collection, and baseline characteristics of participants. The HEUW study recruited 464 participants at baseline, of whom 424 (91.4%) were followed-up at 3 months and 334 (72.0%) at 12 months from baseline. We used standardized and validated questionnaires to collect information on socio-demographic and lifestyle characteristics, medical history, family history of chronic diseases, sleep quality, health-related quality of life, chronotype, psychological distress, occupational factors, and comfort levels with indoor environmental quality parameters. Clinical and anthropometric parameters including blood pressure, spirometry, height, weight, and waist and hip circumference were also measured. Biochemical tests of participants' blood and urine samples were conducted to measure levels of glucose, lipids, and melatonin. We also conducted objective measurements of individuals' workplace environment, assessing air quality, light intensity, temperature, thermal comfort, and bacterial and fungal counts. The findings this study will help to identify modifiable lifestyle and environmental parameters that are negatively affecting workers' health. The findings may be used to guide the development of more health-promoting workspaces that attempt to negate any potential deleterious health effects from working in underground workspaces.

A Multifactorial Approach to Sleep and Its Association with Health-Related Quality of Life in a Multiethnic Asian Working Population: A Cross-Sectional Analysis.

This study aims to explore if objectively and subjectively measured sleep parameters are associated with physical and mental health-related quality of life in a multiethnic working population in Singapore. We performed a cross-sectional analysis with data from 329 full-time employees enrolled in a workplace cohort study in Singapore. The Short-Form 36v2 (SF-36v2) survey was used to assess health-related quality of life, in terms of physical and mental health. Subjective and objective sleep parameters were measured using the Pittsburgh Sleep Quality Index and wrist actigraphy, respectively. Generalized linear modeling was performed to examine the association between sleep parameters and health-related quality of life. After adjusting for confounders, subjectively measured sleep disturbances were associated with a lower physical health-related quality of life, whereas higher, objectively measured sleep efficiency was associated with greater physical health-related quality of life. Subjectively measured daytime dysfunction was associated with impaired mental health-related quality of life. Using both objective and subjective measurements of sleep, the current study suggests that there is an association between sleep and health-related quality of life. Workplace health-promotion planners in Singapore should consider programmes that educate workers on better sleep hygiene practices in an effort to improve sleep and health-related quality of life.

How recommender systems could support and enhance computer-tailored digital health programs: A scoping review.

OBJECTIVE: Tailored digital health programs can promote positive health-related lifestyle changes and have been shown to be (cost) effective in trials. However, such programs are used suboptimally. New approaches are needed to optimise the use of these programs. This paper illustrates the potential of recommender systems to support and enhance computer-tailored digital health interventions. The aim is threefold, to explore: (1) how recommender systems provide health recommendations, (2) to what extent recommender systems incorporate theoretical models and (3) how the use of recommender systems may enhance the usage of computer-tailored interventions. METHODS: A scoping review was conducted, using MEDLINE and ScienceDirect, to identify health recommender systems reported in studies between January 2007 and December 2017. Information was subsequently extracted to understand the potential benefits of recommender systems for computer-tailored digital health programs. Titles and abstracts of 1184 studies were screened for the full-text screening, in which two reviewers independently selected articles and systematically extracted data using a predefined extraction form. RESULTS: A total of 26 articles were included for data extraction. General characteristics were reported, with eight studies reporting hybrid filtering. A description of how each recommender system provides a recommendation is described; the majority of recommender systems used messages as recommendation. We identified the potential effects of recommender systems on efficiency, effectiveness, trustworthiness and enjoyment of the digital health program. CONCLUSIONS: Incorporating a collaborative method with demographic filtering as a second step to knowledge-based filtering could potentially add value to traditional tailoring with regard to enhancing the user experience. This study illustrates how recommender systems, especially hybrid programs, may have the potential to bring tailored digital health forward.

Factors associated with smoking initiation among Saudi male adolescents: A longitudinal study.

INTRODUCTION: Knowing country-specific predictors of smoking behaviour for adolescents is crucial for successful smoking prevention programs. This study aims to assess demographic and socio-cognitive variables related to smoking initiation among Saudi male adolescents. METHODS: Longitudinal data were collected at T1 (baseline) and at T2 (followup at 6 months) using a self-administered questionnaire. We assessed smoking behaviour and related demographic variables and socio-cognitive variables. Chi-squared tests and independent-samples t-tests were used to identify differences in baseline characteristics between smokers and non-smokers at T1. Furthermore, non-smokers at T1 were included in logistic regression analyses to examine the predictors of smoking initiation between T1 and T2. RESULTS: At T1, the non-smokers who were included in further analysis were 523 (84.9%) of whom 48 (9.2%) had initiated smoking at T2. They differed significantly from non-initiators, including having a more positive attitude towards smoking, reporting more social norms, modelling and pressure to smoke, having a lower self-efficacy to refrain from smoking and higher intention to smoke in the future (all p<0.001). The regression analysis revealed that: adolescents with disrupted-families, being of low academic achievement, with relatively high monthly-income families, having more smoking-peers, high-perceived pressure to smoke from parents (p=0.002) and teachers (p=0.001), have smoking supportive-norms of parents and having high intention to smoke in the future (p<0.001) were at higher risk of being smokers. CONCLUSIONS: Findings suggest that health-promoting programs should address strengthening of self-efficacy and enhancing refusal skills against modelling of peers, pressure and norms of parents.