Ik beweeg: Experiment 2.

Rationale:

Physical inactivity is responsible for 8000 deaths per year, 6% of all deaths in the Netherlands, while societal and health care costs are huge. Regular physical activity (PA) is related to improved cardiovascular, respiratory, and muscular function, and the reduction of ZonMw priority diseases diabetes II, cardiovascular diseases, osteoporosis, cancer, and depression. Given that almost half of the Dutch population is insufficiently active, promoting PA among the population is highly important.

Motivational interviewing (MI) has proven its efficacy in changing motivation and PA behaviour. However, MI is an intensive, costly counselling technique, able to reach only limited numbers of people. This makes MI inapt for promoting PA among the large Dutch population.

Computer tailoring (CT) can be a suitable technique to combine individual counselling with a large scale reach. Integrating MI into online CT can be done in different ways. It is possible to communicate the MI strategies by using an online tailoring site that is mostly text driven. However, with recent multimedia developments it is also possible to provide the participant with a virtual coach. Although the actual content would be quite comparable, it is possible that in the setting with the online coach participants feel more relatedness, more competence and more autonomy. This would then result in a higher increase of commitment and intrinsic motivation, and consequently more increase in PA.



Objective:

To identify the additional effects of a computer generated coach on process evaluation, intrinsic motivation, commitment, and PA behavior. Since CT with an integrated coach would be much more expensive to develop and program, it is of huge importance to find out whether these additional costs lead to better results. If not, a large amount of costs can be spared in future MI CT applications.



Study design:

Two group RCT, with measurements at baseline, directly following the intervention and 1 month post intervention. Two MI applications in online CT will be compared: 1) an online MI intervention which includes a virtual coach and 2) an online MI which is mostly text driven, without the additional virtual coach. We expect that the virtual coach integrated condition will result into the highest levels of participation, evaluation and the most optimal effects on intrinsic motivation, commitment and PA behaviour.



Study population:

Participants will be adults, aged between 20 and 65. Participants will be recruited from a Dutch internet panel. Participants can participate in the intervention online, by logging in from their home internet environment. They do not need to travel to a research setting. Estimated sample size = 285.



Interventions:

After giving informed consent participants are automatically assigned to one of two online computer tailored interventions by means of a digital randomizer which is built-in in the website. These two interventions only differ from each other with respect to the presence of a virtual coach: one includes a virtual coach, the other is purely text based.

Both interventions are aimed at intrinsically stimulating initiation and maintenance of regular physical activity among adults. The interventions are based on Motivational Interviewing, which is a client-centered, semi-directive counselling approach of engaging intrinsic motivation to change behaviour by developing discrepancy and exploring and resolving ambivalence within the client.



Study parameters/endpoints:

Physical activity behavior will be assessed using the validated self-administrated International Physical Activity Questionnaire (IPAQ). Changes in the relevant PA related determinants will be assessed using standard reliable scales and existing questionnaires: stage of Change, intention, intrinsic motivation, the degree that participant’s s need for autonomy, competence and relatedness is met and commitment to PA.



Nature and extent of the burden and risks associated with participation, benefit and group relatedness:

Participation in the study will not bring any burden or risks. Benefits of participation in the study will be receiving personalised advice about physical activity for free. Another benefit of participating is helping science gathering data according to innovative scientific perspectives about physical activity and tailoring. This information will be useful for the improvement of health education programs.

An online motivational interviewing intervention which includes a virtual coach results into the higher levels of participation, evaluation and higher effects on intrinsic motivation, commitment and physical activity behaviour, compared to online motivational interviewing intervention which is mostly text driven.

Two group RCT, with measurements at baseline, directly following the intervention and 1 month post intervention. Two MI applications in online CT will be compared:

1. An online MI intervention which includes a virtual coach;

2. An online MI which is mostly text driven, without the additional virtual coach.

We expect that the virtual coach integrated condition will result into the highest levels of participation, evaluation and the most optimal effects on intrinsic motivation, commitment and PA behaviour.

After giving informed consent participants are automatically assigned to one of two online computer tailored interventions by means of a digital randomizer which is built-in in the website. These two interventions only differ from each other with respect to the presence of a virtual coach: one includes a virtual coach, the other is purely text based.



Both interventions are aimed at intrinsically stimulating initiation and maintenance of regular physical activity among adults. People can choose themselves whether or not they continue the intervention, and if they want extra information or not, without there being any consequences. The intervention is based on Motivational Interviewing, which is a client-centered, semi-directive counselling approach of engaging intrinsic motivation to change behaviour by developing discrepancy and exploring and resolving ambivalence within the client.



In both interventions subjects proceed through several parts with questions and exercises. Subjects get computer tailored feedback messages, for example an empathic reflection on a given answer or a short summary in which several answers given by the participant are combined and “interpreted”.



In both interventions, the following elements are addressed:

1. Awareness of one’s current physical activity behaviour and how this relates to the health guidelines;

2. Perceived importance of adopting or maintaining regular physical activity. For example subjects who perceive regular PA as unimportant are encouraged to think of reasons why regular physical activity may be important to them. People who already perceive regular PA as being important receive a positive confirmation;

3. Confidence / self efficacy with regard to becoming or remaining physically active;

4. Intention formation and planning.