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Improving the use (eg, initial visit and revisits) of Internet-delivered interventions to promote healthy lifestyles such as non-smoking is one of the largest challenges in the field of eHealth. Prompts have shown to be effective in stimulating reuse of Internet-delivered interventions among adults and adolescents. However, evidence concerning effectiveness of prompts to promote reuse of a website among children is still scarce.
The aim of this study is to investigate (1) whether prompts are effective in promoting reuse of an intervention website containing information on smoking prevention for children, (2) whether the content of the prompt is associated with its effect in terms of reuse, and (3) whether there are differences between children who do or do not respond to prompts.
The sample of this cluster-randomized study consisted of 1124 children (aged 10-11 years) from 108 Dutch primary schools, who were assigned to the experimental group of an Internet-delivered smoking prevention intervention study. All participants completed a Web-based questionnaire on factors related to (non-)smoking. Schools were randomized to a no-prompt group (n=50) or a prompt group (n=58). All children could revisit the intervention website, but only the children in the prompt group received email and SMS prompts to revisit the website. Those prompt messages functioned as a teaser to stimulate reuse of the intervention website. Reuse of the website was objectively tracked by means of a server registration system. Repeated measures analysis of variance and linear regression analysis were performed to assess the effects of prompts on website reuse and to identify individual characteristics of participants who reuse the intervention website.
Children in the prompt group reused the intervention website significantly more often compared to children in the no-prompt group (
Prompts can stimulate children to reuse an intervention website aimed at smoking prevention. Prompts showed, furthermore, to stimulate children of a low SES slightly more to reuse an intervention website, which is often a difficult target group in terms of stimulating participation. However, the number of revisits was quite low, which requires further study into how prompts can be optimized in terms of content and frequency to improve the number of revisits.
Netherlands Trial Register Number: NTR3116; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3116 (Archived by WebCite at http://www.webcitation.org/6O0wQYuPI).
Smoking prevalence rates among Dutch primary school children increase rapidly when they make the transition to secondary school [
Prior studies have shown that frequent use of an Internet-delivered intervention resulted in higher smoking cessation rates among adults and adolescents [
Reuse of Internet-delivered interventions is dependent on both the intervention characteristics (eg, updates of the intervention website or email contact) and the individual characteristics of the participants [
Prompts can be sent in various ways and the most efficient and low-cost options may be using current technologies [ie, email and short message service (SMS)]. These can be low in cost when compared to conventional postal mail or telephone calls and are relatively easy to implement in Internet-delivered computer-tailored interventions [
The objectives of the present study are to examine (1) whether prompts will stimulate primary school children to reuse a smoking prevention website, (2) whether the prompt content is related to its effect in terms of reuse, and (3) which individual characteristics of children are associated with a higher likelihood to respond to prompts and reuse an intervention website.
The study was conducted as a cluster-randomized controlled trial in which 108 primary schools in the Netherlands were randomized to either a prompt (n=58) or no-prompt group (n=50) of a larger smoking prevention intervention study called “Fun without Smokes” [
In October 2011, all children received personalized log-in codes (username and password) to access the Fun without Smokes website (
Use and reuse of the website was monitored by means of server registrations. Data gathered during the first year of the intervention study (October 2011-September 2012) was used in the analyses. Since prompts were sent via email and SMS, inclusion criteria for the present study were that children had entered a complete and verifiable email address or mobile phone number and that they had indicated they actually use this email address or mobile phone number.
‘Fun without Smokes’ website.
The Fun without Smokes website was accessible to the children in both the prompt and no-prompt groups during the intervention period. Core elements of the Fun without Smokes website were the Web-based questionnaire and the computer-tailored feedback letters. Furthermore, the website provided information on non-smoking through facts concerning non-smoking, anti-smoking games, and short animated videos with non-smoking content. Furthermore, children had the opportunity to ask questions concerning (non-)smoking. To create a website that was most attractive and appreciated, children from the target group were involved in the development process [
In the computer-tailored feedback letters, it was indicated that participants in both the prompt and no-prompt groups were able to reuse the website during the intervention period. Children who had entered an email and/or mobile phone number in the prompt group received 6 prompt messages within 9 months to stimulate them to reuse the Fun without Smokes website. The prompts were sent via email and/or as SMS messages, depending on whether the child had provided an email account and/or mobile phone number and had indicated to use this device. Children received an email and SMS message if they provided both (ie, email address and phone number), otherwise they received only an email or SMS. Children without email or mobile phone did not receive the prompts.
All prompt messages varied in content and were sent at different time periods. The first 3 prompts were sent 1, 2, and 3 months after the baseline questionnaire was completed. The last 3 prompts were sent 5, 7, and 9 months after baseline. In accordance with the prompts, some of the content of the intervention website was refreshed to address a new topic relevant for smoking prevention. The prompts functioned as a teaser to increase curiosity among the children to view the new content at the Fun without Smokes website (eg, “Hi, now there is a funny game on the Fun without Smokes website. Check it out today and play this game!”). The content of the first and second prompt indicated that new facts on (non-)smoking were posted on the website (
Participants in the no-prompt group also had access to the new information, games, and videos. However, reuse of the Fun without Smokes website was dependent on their own initiative since they did not receive any of the 6 prompt messages. They received their personal log-in codes at the baseline measurement of Fun without Smokes and were asked to save those codes. If they lost the codes, they were able to request them at the Fun without Smokes website.
Period and content of prompts posted on the website.
Prompt | Prompt period | Prompt content |
Prompt 1 | 1 month after baseline | Facts about (non-)smoking |
Prompt 2 | 2 months after baseline | New facts about (non-)smoking |
Prompt 3 | 3 months after baseline | New animated videos |
Prompt 4 | 5 months after baseline | Game on (non-)smoking |
Prompt 5 | 7 months after baseline | New facts about (non-)smoking |
Prompt 6 | 9 months after baseline | New game on (non-)smoking |
Primary outcome measure of the present study is reuse of the Fun without Smokes website. Use and reuse of the website was assessed objectively by means of a server registration system. Reuse was measured as a continuous variable, based on the number of clicks (ranging from 0 to 95). Characteristics of the user and reuser such as age, gender ethnicity, and SES were derived from the baseline questionnaire that the children completed in the classroom on the Fun without Smokes website.
Data on website visits was retrieved from a specific server registration system, which made it possible to register website access for each individual child. Using the personal usernames of all participating children, we tracked how often and when (date and time) they reused the Fun without Smokes website.
Reuse of the website was calculated by summing all clicks in the different website components from the first till the last prompt. The clicks in the first month of the intervention period were not included in the calculation since children of both the prompt and no-prompt groups had to complete the Web-based questionnaire at their primary school and no prompt messages were sent in this period. By using this approach, reuse of the intervention website indicates how intensively the website was reused after the prompts were sent.
Availability of email addresses for the participating children was measured in the Web-based questionnaire. Children were able to fill out their email address (scored as “1”) or indicate if they had no email address or had forgotten their email address (scored as “0”). Children could also indicate whether they actually used their email address (coded 1) or not (coded 0).
Availability of mobile phone numbers for the participants was also measured in the questionnaire. Children having a mobile phone number were scored with a “1”, whereas children without a mobile phone number or if they had forgotten their mobile phone number were scored with a “0”. Children could also indicate whether they actually used their mobile phone (coded 1) or not (coded 0).
In the questionnaire, the following background variables were measured: age (in years), gender (1=boy; 2=girl), ethnicity, and SES of the participants. Ethnicity indicated whether a child had a Western or non-Western background. A child was considered to be of Western ethnic background (coded 1) if he or she and both parents had been born in the Netherlands, another European country, North America, Oceania, Indonesia (a former colony of the Netherlands), or Japan. Otherwise the child was considered to be of non-Western ethnic background (coded 2) [
The data from the server registration system and the data from the baseline questionnaire could be linked by means of the personal usernames, making it possible to unobtrusively observe if a participant reused the intervention website after a prompt message was sent and to combine usage information with individual data of the users.
General descriptives were carried out to describe the sample under study. Differences at baseline between characteristics of children (ie, age, gender, ethnicity, SES, having/using their email address, and having/using their mobile phone) in the no-prompt and prompt group were analyzed with chi-square and
A multiple linear regression analysis was conducted to identify whether there was a difference in website reuse between the prompt and the no-prompt groups. In this analysis, reuse of the intervention website was the dependent variable, and group and demographic characteristics were the independent variables. To identify whether there were differential effects of the prompt condition based on demographic characteristics, a linear regression analysis was done that included group*demographic variable interaction terms (ie, age, gender, ethnicity, or SES). If interaction effects were present, separate analyses were performed for two subgroups of a variable.
To indicate which prompt(s) motivated children most to reuse the Fun without Smokes website, a repeated-measures analysis of variance (ANOVA) was carried out. In this analysis, the number of clicks in the separate prompt periods were analyzed between the prompt and no-prompt group. All analyses were performed in SPSS 20.0.
A total of 1124 children met the inclusion criteria and were included in the analyses (13.87%, 181/1305, were excluded). As shown in
Mean reuse of the intervention website was 2.14 times (SD 7.53) in the prompt group and 0.47 times (SD 2.30) in the no-prompt group and this difference was significant (
Mean reuse of the intervention website in the prompt group among children of low SES was 3.03 times (SD 9.84) and among high SES children 1.37 times (SD 4.62). Moreover,
Basic characteristics.
Characteristic | Total sample |
Prompt |
No prompt |
|
X2 | df |
|
Age in years, mean (SD) | 10.35 (0.57) | 10.32 (0.56) | 10.38 (0.57) | 1.62 | - | 1098 | .11 |
Gender, n (%) girl | 623 (55.43) | 336 (57.34) | 287 (53.35) | - | 1.81 | 1 | .18 |
Ethnicity, n (%) Western | 961 (85.50) | 500 (85.32) | 461 (85.69) | - | 0.03 | 1 | .86 |
SESa, n (%) high SES | 484 (43.06) | 245 (41.81) | 239 (44.42) | - | 0.13 | 1 | .72 |
Email address, n (%) yes | 1120 (99.64) | 585 (99.83) | 535 (99.44) | - | 1.18 | 1 | .28 |
Email address use, n (%) yes | 1107 (98.49) | 577 (98.46) | 530 (98.51) | - | 0.46 | 1 | .50 |
Mobile phone, n (%) yes | 175 (15.57) | 84 (14.33) | 91 (16.91) | - | 0.14 | 1 | .71 |
Mobile phone use, n (%) yes) | 169 (15.04) | 83 (14.16) | 86 (15.99) | - | 2.44 | 1 | .12 |
aSES: socioeconomic status
Interaction effects between subgroups and group on reuse of the intervention websitea.
Group/subgroup |
|
95% CI |
|
Age | −1.65 | −4.58 to 1.28 | .27 |
Gender (1=male; 2=female) | 0.82 | −2.50 to 4.13 | .63 |
Ethnicity (1=Western; 2=non-Western) | −0.43 | −5.11 to 4.26 | .86 |
SESb (0=low SES; 1=high SES) | 2.26 | −1.03 to 5.55 | .18 |
Group (0=no prompt; 1=prompt) | −5.76 | −17.95 to 6.44 | .36 |
Age*Group | 0.77 | −0.37 to 1.92 | .19 |
Gender*Group | −0.17 | −1.46 to 1.13 | .80 |
Ethnicity*Group | 0.16 | −1.68 to 1.99 | .87 |
SES*Group | −1.22 | −2.50 to 0.07 | .06 |
a
bSES: socioeconomic status
In
Means of reuse of the "Fun without Smokes" website between prompt and no-prompt group. X-axis time points: prompt 1= 1 month; prompt 2= 2 months; prompt 3= 3 months; prompt 4= 5 months; prompt 5= 7 months; prompt 6= 9 months.
The aims of the present study were to investigate whether prompt messages (via email and SMS) were effective in stimulating primary school children to reuse an intervention website containing information on non-smoking, to assess whether the prompt content was associated with the reuse of the intervention website, and whether there were differences in characteristics between children who responded or did not respond to the prompt messages. Results indicated that prompts had a positive effect on reuse of the intervention website; in particular, prompts that announced new animated movies or games increased reuse more than prompts that announced new information on the website. Additionally, children with a low SES seemed to be even more responsive to the prompts than children with a high SES.
This was the first study on the effects of prompts via email and SMS on reuse of a smoking prevention website among children. Even though the prompt messages seemed to improve website reuse, the total website reuse was still very low, though comparable with what has been found for adults and adolescents [
The effects of prompts appeared promising for low SES children. This is especially relevant for them since they suffer more often from health problems than high SES groups [
A major strength of the present study is the large and diverse sample, since a representative sample of grade 7 children from all regions in the Netherlands was included. The majority of previous studies conducted observational research or lab studies [
Prompt messages via email and SMS can improve reuse of an intervention website with information on smoking prevention among children. Specifically, prompt messages that announced animated videos and games concerning non-smoking stimulated children most to reuse the website. Furthermore, prompt messages seemed to stimulate children of low SES slightly more than high SES children to reuse the intervention website.
CONSORT-EHEALTH checklist V1.6.2 [
analysis of variance
socioeconomic status
short message service
This work was supported by ZonMw, the Netherlands Organization for Health Research and Development (200110011).
Hein de Vries is scientific director of Vision2Health, a company that licenses evidence-based innovative computer-tailored health communication tools. The other authors declare that they have no competing interests.