How could strategies which aim to improve dissemination of and exposure to Internet-delivered interventions be tested on effectiveness?
It is recommended (Crutzen, De Nooijer, Brouwer, Oenema, Brug, & De Vries, submitted) to conduct experimental research in more controlled settings to increase evidence-based insight into effectiveness of strategies regarding dissemination of and exposure to Internet-delivered interventions, before applying these strategies in practice. Advantage of such a controlled setting is the minimisation of possible confounding effects. Disadvantage of these experimental settings, however, is the isolated way in which strategies are tested on effectiveness, which is less comparable with real-life implementation.
Even if strategies are immediately applied in practice, there are appropriate designs, such as a time series design (Chen et al., 2005; Murry, Stam, & Lastovicka, 1993), to test effectiveness of these strategies. In such a design, strategies are first applied separately. Subsequently, combinations of several strategies are applied. Intervention use is monitored during the whole period to determine which strategy or combination between them is most effective. Although this design is more sensitive to confounding effects (e.g. changing environment), strategies are tested in a less isolated way and this could give more insight into effectiveness regarding dissemination and exposure in real life.
If all methods described above are inapplicable due to limited resources, one could test the effectiveness of dissemination strategies by simply asking visitors where they came from and how they heard about the intervention (Gordon, Akers, Severson, Danaher, & Boles, 2006). Although this method is based on self-report and therefore less objective, it is easily applicable and less time consuming. Yet, this method remains a last resort (when all else fails).
Dissemination and exposure do not only depend on the intervention itself, however, but also on its users. There is evidence that the acquisition of skills to use a website may influence its adoption (Paswan & Ganesh, 2003). It has also been shown, however, that Internet self-efficacy is not a significant predictor of exposure (Steele, Mummery, & Dwyer, 2007). If familiarity with a website increases, then perceived usability influences loyalty to the website (Casaló, Flavián, & Guinalíu, 2008). This is in line with the principle of cognitive lock-in, accounting for users’ preference of better-known websites (Murray & Häubl, 2002). In terms of Internet-delivered interventions, this could be conducive to revisits of the intervention.
Implications for practice
Caution regarding the use of strategies to improve dissemination and exposure is recommended as long as evidence-based insight into effectiveness is scarce. Evidence-based insight into strategies which aim to improve dissemination and exposure, however, could also be gained by applying strategies in practice and investigating, for example, server registrations (objective) or visitors’ self-reporting (subjective). Applying strategies in practice can be seen as natural experiments to test effectiveness of these strategies. Although this research method is more common in fields where laboratory experiments are more difficult, such as sociology and economics (Angrist & Evans, 1998), there are also examples in the field of health promotion – e.g. with regard to the effect of a smoking ban (Sargent, Shepard, & Glantz, 2004).
Implications for future research
To increase evidence-based insight into effectiveness of strategies regarding dissemination and exposure, future research should not be limited to experimental research in controlled settings, but also use alternatives such as a time series design. Such a time series design can also be used to test effectiveness of dissemination strategies for existing Internet-delivered interventions.
References:
Angrist, J., & Evans, W. (1998). Children and their parents’ labor supply: evidence from exogenous variation in family size. American Economic Review, 88, 450-477.
Casaló, L., Flavián, C., & Guinalíu, M. (2008). The role of perceived usability, reputation, satisfaction and consumer familiarity on the website loyalty formation process. Computers in Human Behavior, 24, 325-345.
Chen, J., Smith, B. J., Loveday, S., Bauman, A., Costello, M., Mackie, B., et al. (2005). Impact of a mass media campaign upon calls to the New South Wales Hep C helpline. Health Promotion Journal of Australia, 16, 11-14.
Crutzen, R., De Nooijer, J., Brouwer, W., Oenema, A., Brug, J., & De Vries, N. K. (submitted). Strategies to facilitate exposure to Internet-delivered health behaviour change interventions aimed at adolescents or young adults: a systematic review.
Gordon, J. S., Akers, L., Severson, H. H., Danaher, B. G., & Boles, S. M. (2006). Successful participant recruitment strategies for an online smokeless tobacco cessation program. Nicotine & Tobacco Research, 8, S35-S41.
Murray, K. B., & Häubl, G. (2002). The fiction of no friction: A user skills approach to cognitive lock-in. Advances in Consumer Research, 29, 8-10.
Murry, J. P., Stam, A., & Lastovicka, J. L. (1993). Evaluating an anti-drinking and driving advertising campaign with a sample survey and time series intervention analysis. Journal of the American Statistical Association, 88, 50-56.
Paswan, A. K., & Ganesh, G. (2003). Familiarity and interest: in a learning center service context. Journal of Services Marketing, 17, 393-419.
Sargent, R. P., Shepard, R. M., & Glantz, S. A. (2004). Reduced incidence of admissions for myocardial infarction associated with public smoking ban: before and after study. British Medical Journal, 328, 977-980.
Steele, R. M., Mummery, W. K., & Dwyer, T. (2007). Examination of program exposure across intervention delivery modes: face-to-face versus internet. International Journal of Behavioral Nutrition and Physical Activity, 4, 7.