Assessing the use of a portable time-geographic diary for detecting patterns of daily occupations

Figures & data

Figure 1. User interface of the PODD smartphone application. (a) Login page. (b) Application start page composed of (1) navigation and menu buttons, (2) main performed activity entry, (3) secondary activity entry, (4) additional variables describing the performed activity, such as place, companionship, and mood.

Figure 2. Process of entering activities using the PODD smartphone application. (a) Start page with main activity about to be updated. (b) First a selection between the 8 main categories of the coding scheme is made, e.g. Transportation, then (c) the selection is refined by scrolling down in the coding scheme to add more detailed activity descriptions, e.g. travel by car. (d) Additional variables describing the activity are specified, e.g. place is set to road. (e) Activity is set and (f) main page is updated.

Figure 3. Calendar view of PODD displaying the start time and duration of activities performed (colour coded) as well as secondary activity and additional variables such as place, companionship, and mood (in blue).

Table 1. Overview of participants and number of diaries uploaded.

Characteristics		Diaries (n)	Questionnaire
Age (years) median (md)	20 − 42 (26)
Gender	31	75	20
Male	6	13	5
Female	25	62	15
Diaries collected
Monday-Friday		51
Saturday-Sunday		24
Logged activities duration (minutes) (mean)		2 − 291 (37)

Table 2. The participating students’ ratings of the overall usability and the five quality components (n = 20).

Variables	Median	Mean	(SD)
Overall Usability
Sense of confidence when using PODD*	5	4.2	(0.8)
Positive experience of using PODD as a diary	4	3.7	(0.8)
Logged days representative of their current everyday life	4	3.8	(0.8)
Learnability
I think it is easy to learn and understand how to:
Upload diary data	4	4.3	(0.8)
Use the start menu	5	4.4	(0.7)
Use the calendar function	4	3.9	(1.0)
Use the history function	4	4.3	(0.9)
Efficiency
How quickly and efficient is it to navigate?
Good overview and quick control*	5	4.3	(0.7)
Quick and easy to start using the PODD	5	4.3	(0.8)
Quick and easy interpretation of calendar function	4	3.7	(1.3)
Quick interpretation and use of history function	5	4.3	(0.9)
I think I would use it frequently*	3	3.1	(1.1)
Memorability
Did you remember how to navigate in the application when starting up a new diary/activity?
I needed to learn a lot before I could start using the PODD*	1	1.5	(0.9)
The application was complicated to use*	2	1.8	(0.9)
I think there were too many steps and inconsistencies in the application*	2	2.0	(0.8)
The application was easy to understand and use*	4	4.1	(0.8)
Errors
Did you experience mistakes and needed technical support?
Needed technical support to get started*	1	1.3	(0.6)
Experienced that I made mistakes*	2	2.1	(1.0)
Satisfaction
How pleasant is it to use PODD?
Easy to use not complicated at all	4	4.1	(0.8)
Most individuals (with or without disabilities) can certainly learn to use it*	4	3.7	(0.8)
Useful to see the PDO in the calendar function	5	4.3	(0.9)

Md = median, m = mean, SD = standard deviation. 1 = strongly disagree, 2 = disagree, 3 = neither agree nor disagree, 4 = agree, 5 = strongly agree. *Items inspired by the System Usability Scale (Brooke, 1996).