Operación y control del sistema de tratamiento

A principal component analysis (PCA) was also conducted for the patients’ model which in total comprised of 38 items. Similar to the physicians, this study used the principal component analysis with oblique rotation, i.e., direct oblimin rotation, and tested this on all TR dimensions, complexity, compatibility and the TAM items with regards to the patients’ sample. Similar to the physicians group, all factors below .30 are suppressed. As noted before, Stevens (2002) mentions that the significance of the factor loading will also depend on the sample size. The sample of the patients is much higher than the physicians, namely 398. Stevens (2002) recommends that for a sample size of 300 the loading should be greater than .298. Therefore, to be conservative, all factors below 0.298 are suppressed. It is important to start by testing the assumptions of the factor analysis. This can be done using Bartlett's test of sphericity. The Bartlett's test of sphericity was significant (χ2 (7292) = 528 df, p < .001) indicating that correlations between items were sufficiently large for PCA. Furthermore, Kaiser-Meyer-Olkin measure of sampling adequacy was .894 which is well above the commonly recommended value of 0.5. Hutcheson and Sofroniou (1999) mention that values between 0.8 and 0.9 are great and values above 0.9 are superb. So the sample is definitely adequate for factor analysis.

The initial factor analysis showed 7 components where items grouped together while there are 8 variables tested. It became evident that compatibility and intention to use loaded both onto the same factor whereas intention to use showed much higher factor loadings. However, when the questions are analysed it is not logical to combine both constructs with each other as they clearly measure other things. Furthermore, two factor loadings showed values less than .298 which were, together with the compatibility items, excluded step wise where the lowest loadings are excluded first. Compatibility will still be used in the reliability analysis and also in the regression analysis due to an expected correlation with perceived usefulness. In short, the total number of 38 items used for the factor analysis is reduced to a total of 33 items which are used for further analysis. So two items showed a value lower than .298. These items belong in the original discomfort construct. The item ONG_05 was the statement: “There should be caution in replacing important people tasks with technology because new technology can breakdown or get disconnected” appeared to have a low factor loading of <.298. And ONG_07, "Technology always seems to fail at the worst possible time'' also loaded very low. A reason for these low factor loadings could be that the questions are too ambiguous for the respondent to be associated with discomfort. For example, "new technology could break down" could be interpreted as not really measuring a real feeling but more an annoyance and similarly, "technology seems to fail at the worst possible time" could also lead people to think of one or two incidents but not a general feeling, or discomfort towards technology. There seems to be a problem with these items in the discomfort construct as they were also excluded in the physicians' sample. In appendix I it is also shown in a scheme exactly which items are excluded by the factor analysis for both patients and physicians. The seven components together explained 66.24% of the variance. Table 5.24 shows the results from the factor analysis for both the TRI dimensions and the variables intention to use, perceived usefulness, complexity, and compatibility. No factors were excluded from the analysis except the compatibility construct which loaded on the same component as intention to use and two items in the discomfort construct that did not load significantly (i.e., ≤.298).

Table 5.24: Patients Factor analysis

TR Dimensions PU DIS INN OPT INS CX ITU

Optimism

1. Technology gives people more control over -,769

their daily lives

2. Products and services that use the newest -,754

technologies are much more convenient to use

3. You prefer to use the most advanced -,675

technology available

4. Technology makes you more efficient in -,641

your occupation

5. Technology gives you more freedom of -,800

Mobility

6. You feel confident that machines will follow -,694

through with what you instructed them to do

Innovativeness

7.Other people come to you for advice on new ,655

technologies

8. In general, you are among the first in your circle ,768

of friends to acquire new technology when it appears

9. You can usually figure out new high-tech ,826

products

and services without help from others

10. You keep up with the latest technological ,806

developments in your areas of interest

11. You find you have fewer problems than other ,872

people in making technology work for you

Discomfort

12. Technical support lines are not helpful ,806

because they

do not explain things in terms you understand

13. Sometimes, you think that technology systems are ,827

not designed for use by ordinary people

14. There is no such thing as a manual for a high-tech ,795

product service that is written in plain language

15. If you buy a high-tech product or service, you ,575

prefer to have the basic model over one with a lot of extra features

16. Many new technologies have health or safety risks ,326 ,446 that are not discovered until after people have used them

Insecurity (INS)

17. Critics lead people to believe that revolutionary ,461

new technologies are less safe than they usually are

18. A machine or computer is going to be less reliable ,458 -,321 in doing a task than a person

19. It can be risky to switch to a revolutionary new ,759

technology too quickly.

20. If you buy products that are too high-tech, you may ,758

get stuck without replacement parts or service.

21. Technological innovations always seem to ,476

hurt a lot of people by making their skills obsolete.

Perceived Usefulness (PU)

22. I expect that using the artificial pancreas ,832 improves my performance in daily life

23. I expect that using the artificial pancreas ,853

in my daily life increases my productivity.

24. I expect that using the artificial pancreas ,865

enhances my effectiveness in daily life.

25. I expect that the artificial pancreas will ,502

be useful in my daily life.

26. I expect that using the artificial pancreas would ,804

enable me to accomplish tasks more quickly.

27. I expect that using the artificial pancreas ,680

would make it easier for me to accomplish my daily activities.

Complexity (CX)

28. I expect that using the artificial pancreas will -,808

take too much time from my normal duties.

29. I expect that working with the artificial pancreas is so -,819

complicated, it is difficult to understand what is going on.

30. I expect that using the artificial pancreas involves too -,749

31. I expect that it takes too long to learn how -,811

to use an artificial pancreas to make it worth the effort.

Intention to Use (ITU)

32. Assuming I have access to an artificial ,823

pancreas, I intend to use it.

33. Assuming I have access to the artificial ,880

pancreas, I predict that I would use it

Note. Factor loadings that are grouped together are in boldface, factor loadings <.298 are suppressed, OPT = Optimism, INN = Innovativeness, DIS = Discomfort, DIS = Discomfort, INS = Insecurity adapted from Godoe & Johansen (2012), Parasuraman (2000), Walczuch et al. (2007), Lin et al. (2007)