Liesbeth van Osch

Measuring risk perceptions of skin cancer: Reliability and validity of different operationalizations

OBJECTIVE Risk perceptions play a pivotal role in health behaviour theories. Accurate measurement is essential in order to investigate the explanatory value and effectiveness of interventions influencing these beliefs. This study investigated the reliability and predictive validity of different risk perception operationalizations related to skin cancer and sunscreen use in order to explain the inconsistent findings in literature regarding the relationship between risk perceptions and (cancer related) behaviours. DESIGN AND METHODS Two on-line surveys were conducted. Study 1 (N= 175) was conducted among university students to investigate the test-retest reliability of different operationalizations of perceived likelihood and perceived severity and to assess their correlations with sunscreen use. Study 2 (N= 418) was a prospective study among Dutch adults and assessed longitudinal correlations between the different operationalizations and sunscreen use. RESULTS Internal consistency (alpha) ranged between .13 and .90 for likelihood measures and between .37 and .88 for severity measures. Test-retest correlations (r/ICC) ranged between .51 and .82 for the likelihood measures and between .58 and .75 for the severity measures. Conditional likelihood estimates, particularly when phrased affectively (feeling at risk), and comparative severity questions were the strongest correlates of behaviour. CONCLUSION Conditional likelihood and comparative severity might be better predictors of health behaviour than commonly used operationalizations of risk perception. These measures may be relevant for use in the development and evaluation of intervention programmes, and should be acknowledged by health behaviour theories. Suggestions for future research are discussed.

Identifying Factors for Optimal Development of Health-Related Websites: A Delphi Study Among Experts and Potential Future Users

Background The Internet has become a popular medium for offering tailored and targeted health promotion programs to the general public. However, suboptimal levels of program use in the target population limit the public health impact of these programs. Optimizing program development is considered as one of the main processes to increase usage rates. Objective To distinguish factors potentially related to optimal development of health-related websites by involving both experts and potential users. By considering and incorporating the opinions of experts and potential users in the development process, involvement in the program is expected to increase, consequently resulting in increased appreciation, lower levels of attrition, and higher levels of sustained use. Methods We conducted a systematic three-round Delphi study through the Internet. Both national and international experts (from the fields of health promotion, health psychology, e-communication, and technical Web design) and potential users were invited via email to participate. During this study an extensive list of factors potentially related to optimal development of health-related websites was identified, by focusing on factors related to layout, general and risk information provision, questionnaire use, additional services, and ease of use. Furthermore, we assessed the extent to which experts and potential users agreed on the importance of these factors. Differences as well as similarities among experts and potentials users were deduced. Results In total, 20 of 62 contacted experts participated in the first round (32% response rate); 60 of 200 contacted experts (30% response rate) and 210 potential users (95% response rate) completed the second-round questionnaire, and 32 of 60 contacted experts completed the third round (53% response rate). Results revealed important factors consented upon by experts and potential users (eg, ease of use, clear structure, and detailed health information provision), as well as differences regarding important factors consented upon by experts (eg, visual aids, self-monitoring tool, and iterative health feedback) or by potential users only (eg, bread crumb navigation and prevention of receiving spam). Conclusions This study is an important first step in determining the agreed-upon factors that should be taken into account when developing online health promotion programs. The public health impact of these programs will be improved by optimizing the development process in line with these factors.

From theory to practice: An explorative study into the instrumentality and specificity of implementation intentions

Objective: The present study explores the behavioural impact of instrumentality and specificity of implementation intentions. Method: At baseline, 764 participants in a smoking cessation contest were asked to formulate three implementation intentions on how they planned to cope with difficult situations. Two independent researchers evaluated all formulated plans and rated them according to their instrumentality (instrumental and non-instrumental) and specificity (non-specific, medium and highly specific). Point prevalence and continuous smoking abstinence rates were measured 7 months after baseline. Results: One in four participants (23%) made at least one non-instrumental implementation intention. On average, participants made medium to highly specific plans. The mere instrumentality of plans did not significantly affect smoking abstinence. Plan specificity positively predicted point prevalence abstinence; medium to highly specific planning resulted in higher abstinence rates than less specific planning. Smoking abstinence rates did not differ between respondents with medium and highly specific planning. Women, higher educated participants, and experienced quitters were more likely to formulate instrumental implementation intentions. Women and highly motivated participants were more specific in their planning. Conclusion: By encouraging participants to furnish goal-directed actions with sufficient detail the efficacy of implementation intention formation can be increased. Implications for future studies and interventions are discussed.

Periodic Email Prompts to Re-Use an Internet-Delivered Computer-Tailored Lifestyle Program: Influence of Prompt Content and Timing

Background Adherence to Internet-delivered lifestyle interventions using multiple tailoring is suboptimal. Therefore, it is essential to invest in proactive strategies, such as periodic email prompts, to boost re-use of the intervention. Objective This study investigated the influence of content and timing of a single email prompt on re-use of an Internet-delivered computer-tailored (CT) lifestyle program. Methods A sample of municipality employees was invited to participate in the program. All participants who decided to use the program received an email prompting them to revisit the program. A 2×3 (content × timing) design was used to test manipulations of prompt content and timing. Depending on the study group participants were randomly assigned to, they received either a prompt containing standard content (an invitation to revisit the program), or standard content plus a preview of new content placed on the program website. Participants received this prompt after 2, 4, or 6 weeks. In addition to these 6 experimental conditions, a control condition was included consisting of participants who did not receive an additional email prompt. Clicks on the uniform resource locator (URL) provided in the prompt and log-ins to the CT program were objectively monitored. Logistic regression analyses were conducted to determine whether prompt content and/or prompt timing predicted clicking on the URL and logging in to the CT program. Results Of all program users (N=240), 206 participants received a subsequent email prompting them to revisit the program. A total of 53 participants (25.7%) who received a prompt reacted to this prompt by clicking on the URL, and 25 participants (12.1%) actually logged in to the program. There was a main effect of prompt timing; participants receiving an email prompt 2 weeks after their first visit clicked on the URL significantly more often compared with participants that received the prompt after 4 weeks (odds ratio [OR] 3.069, 95% CI 1.392-6.765, P=.005) and after 6 weeks (OR 4.471, 95% CI 1.909-10.471, P=.001). Furthermore, participants who received an email prompt 2 weeks after their first visit logged in to the program significantly more often compared to participants receiving the prompt after 6 weeks (OR 16.356, 95% CI 2.071-129.196, P=.008). A trend was observed with regard to prompt content. Participants receiving a prompt with additional content were more likely to log in to the program compared to participants who received a standard prompt. However, this result was not statistically significant (OR 2.286, 95% CI 0.892-5.856, P=.09). Conclusions The key findings suggest that boosting revisits to a CT program benefits most from relatively short prompt timing. Furthermore, a preview of new website content may be added to a standard prompt to further increase its effectiveness in persuading people to log in to the program.

Thinking versus feeling: Differentiating between cognitive and affective components of perceived cancer risk

Despite the increased recognition of affect in guiding probability estimates, perceived risk has been mainly operationalised in a cognitive way and the differentiation between rational and intuitive judgements is largely unexplored. This study investigated the validity of a measurement instrument differentiating cognitive and affective probability beliefs and examined whether behavioural decision making is mainly guided by cognition or affect. Data were obtained from four surveys focusing on smoking (N = 268), fruit consumption (N = 989), sunbed use (N = 251) and sun protection (N = 858). Correlational analyses showed that affective likelihood was more strongly correlated with worry compared to cognitive likelihood and confirmatory factor analysis provided support for a two-factor model of perceived likelihood instead of a one-factor model (i.e. cognition and affect combined). Furthermore, affective likelihood was significantly associated with the various outcome variables, whereas the association for cognitive likelihood was absent in three studies. The findings provide support for the construct validity of the measures used to assess cognitive and affective likelihood. Since affective likelihood might be a better predictor of health behaviour than the commonly used cognitive operationalisation, both dimensions should be considered in future research.

Testing a Dutch web-based tailored lifestyle programme among adults: a study protocol

BackgroundSmoking, high alcohol consumption, unhealthy eating habits and physical inactivity often lead to (chronic) diseases, such as cardiovascular diseases and cancer. Tailored online interventions have been proven to be effective in changing health behaviours. The aim of this study is to test and compare the effectiveness of two different tailoring strategies for changing lifestyle compared to a control group using a multiple health behaviour web-based approach.MethodsIn our Internet-based tailored programme, the five lifestyle behaviours of smoking, alcohol intake, fruit consumption, vegetable consumption, and physical activity are addressed. This randomized controlled trial, conducted among Dutch adults, includes two experimental groups (i.e., a sequential behaviour tailoring condition and a simultaneous behaviour tailoring condition) and a control group. People in the sequential behaviour tailoring condition obtain feedback on whether their lifestyle behaviours meet the Dutch recommendations. Using a step-by-step approach, they are stimulated to continue with a computer tailored module to change only one unhealthy behaviour first. In the course of the study, they can proceed to change a second behaviour. People in the simultaneous behaviour tailoring condition receive computer tailored feedback about all their unhealthy behaviours during their first visit as a stimulation to change all unhealthy behaviours. The experimental groups can re-visit the website and can then receive ipsative feedback (i.e., current scores are compared to previous scores in order to give feedback about potential changes). The (difference in) effectiveness of the different versions of the programme will be tested and compared to a control group, in which respondents only receive a short health risk appraisal. Programme evaluations will assess satisfaction with and appreciation and personal relevance of the intervention among the respondents. Finally, potential subgroup differences pertaining to gender, age and socioeconomic status regarding the behaviour effects and programme evaluation will be assessed.DiscussionResearch regarding multiple behaviour change is in its infancy. We study how to offer multiple behaviour change interventions optimally. Using these results could strengthen the effectiveness of web-based computer-tailoring lifestyle programmes. This study will yield new results about the need for differential lifestyle approaches using Internet-based expert systems and potential differences in subgroups concerning the effectiveness and appreciation.Trial registrationDutch Trial Register NTR2168.

Predicting parental sunscreen use: Disentangling the role of action planning in the intention–behavior relationship

Structural equation modeling was used to examine antecedents of parental sunscreen use (N = 436) in a longitudinal design. The influence of a volitional planning cognition was assessed in several path models, investigating potential mediation and moderation of the intention–behavior relationship. Premotivational and motivational variables accounted for 55.1% of the variance in intention to use sunscreen. Intention emerged as the most powerful predictor of behavior, followed by action planning and self-efficacy expectations, together explaining 35.4% of parental sunscreen use after five months. Strong support was found for both mediating and moderating influences of action planning on the intention–behavior relationship. Action planning also partially mediated the impact of self-efficacy on behavior. The results support theoretical considerations to add postintentional cognitions to current health behavior models. Although action planning is an important component in the transition from intention to behavior, the impact of intention and of other premotivational and motivational variables should not be overlooked when developing health educational interventions.

The influence of narrative risk communication on feelings of cancer risk

OBJECTIVE Evidence is accumulating for the importance of feelings of risk in explaining cancer preventive behaviours, but best practices for influencing these feelings are limited. The aim of this experimental study was to compare the effects of narrative and non-narrative risk communication about sunbed use on ease of imagination and feelings of cancer risk. DESIGN AND METHODS A total of 233 female sunbed users in the general Dutch population were randomly assigned to one of three conditions: a narrative message (i.e., personal testimonial), a non-narrative cognitive message (i.e., factual risk information using cognitive-laden words), or a non-narrative affective message (i.e., factual risk information using affective-laden words). Ease of imagination and feelings of risk were assessed directly after the risk information was given (T1). Three weeks after the baseline session, feelings of risk were measured again (T2). RESULTS The results revealed that sunbed users who were exposed to narrative risk information could better imagine themselves developing skin cancer and reported higher feelings of skin cancer risk at T1. Moreover, ease of imagination mediated the effects of message type on feelings of risk at T1 and T2. CONCLUSION The findings provide support for the effects of narrative risk communication in influencing feelings of cancer risk through ease of imagination. Cancer prevention programmes may therefore benefit from including narrative risk information. Future research is important to investigate other mechanisms of narrative information and their most effective content and format. STATEMENT OF CONTRIBUTION What is already known on this subject? Evidence is growing for the importance of feelings of risk in explaining cancer preventive behaviours. Narratives have increasingly been considered as an effective format for persuasive risk messages and studies have shown narrative risk communication to be effective in influencing cognitive risk beliefs. What does this study add? Increasing understanding of how feelings of cancer risk can be influenced since best practices for influencing these feelings are limited. Extending knowledge about the underlying mechanisms of narrative effects on feelings of cancer risk (i.e., the mediating role of ease of imagination) using a non-student sample. The findings provide support for the effects of narrative risk communication in influencing feelings of cancer risk through ease of imagination.

Optimizing the efficacy of smoking cessation contests: an exploration of determinants of successful quitting

The present study describes the short- and long-term efficacy and program evaluation of a Quit and Win smoking cessation campaign, organized in The Netherlands. To be able to fine-tune smoking cessation contests to the needs of the target population, utilization, appreciation and efficacy of various contest elements were investigated. Data from 1,551 Quit and Win participants and 244 control respondents were collected by web-based surveys at baseline (pre-contest) and 1 and 12 months after the contest. Demographic and contest predictors of successful quitting were determined by logistic regression analyses. Quit and Win proved to be an effective as well as highly appreciated program among participants. Conservative 1-month (35%) and continuous 12-month abstinence (12%) rates were significantly higher in Quit and Win participants than in the control group (1 month: 11%; continuous: 3%). Use of a supportive e-mail message service predicted short- and long-term abstinence. A buddy support system was the most used and highly appreciated cessation aid, and its use significantly predicted short-term abstinence. Radio commercials and Internet advertisements were the most effective recruitment channels. Although non-exhaustive, implementation of the results and recommendations discussed in this study could lead to an increased use, appreciation and efficacy of future smoking cessation campaigns.

Internet-Based Computer Tailored Feedback on Sunscreen Use

Background Skin cancer incidence rates signify the need for effective programs for the prevention of skin cancer and for helping skin cancer patients. Internet and computer tailored (CT) technology fosters the development of highly individualized health communication messages. Yet, reactions to Internet CT programs may differ per level of involvement and education level and remain understudied. Objective First, we identified perceptions concerning sunscreen use in Dutch adults and assessed differences in differences between the general public and skin cancer patients, and between low and high educated respondents. Second, we assessed program evaluations of these groups about a new Dutch CT Internet-based program promoting sunscreen use, and potential differences between groups Methods A cross-sectional research design was used. In total, 387 respondents participated and filled out an online questionnaire based on the I-Change Model assessing socio-demographics, history of skin cancer, sunscreen use, and beliefs about sunscreen use. The responses were fed into a computer program that generated personal tailored feedback on screen; next we assessed their program evaluations Results Of the 132 patients, 92 were female (69.7%) and 40 were male (30.3%). In the general population (N = 225), 139 (54.5%) respondents were female and 116 (45.5%) were male. Men (50.9 years) were 8 years older than women (43.1 years). Most patients were diagnosed with basal cell carcinoma (N = 65; 49.2%), followed by melanoma (N = 28; 21.2%) and squamous cell carcinoma (N = 10; 7.6%); 22% (N = 29) did not remember their skin cancer type. Patients had higher knowledge levels, felt significantly more at risk, were more convinced of the pros of sunscreen, experienced more social support to use sunscreen, had higher self-efficacy, and made more plans to use sunscreen than respondents without skin cancer (N=255; all P’s< .01). Low (N=196) educated respondents scored lower on knowledge (P<.003) but made more action plans (P<.03) than higher educated respondents (N=191). The CT feedback was evaluated positively by all respondents, and scored a 7.8 on a 10 point scale. Yet, patients evaluated the CT program slightly more (P<.05) positive (8.1) than non-patients. (7.6). Lower educated respondents were significantly (P<.05) more positive about the advantages of the program. Conclusions First, involvement with skin cancer was reflected in more positive beliefs toward sunscreen use in patients in comparison with non-patients. Second, the CT Internet program was well accepted by both patients and non-patients, and low and high educated respondents, perhaps because higher educated respondents were more knowledgeable about sunscreen use and skin cancer. Third, a pro-active approach as conducted in our study is very well suited to reach various groups of people and is more likely to be successful than a reactive approach