Table 9. Barriers related to the PHR itself.

	Usability	Cost	Lack of information
Implementation phase:
1 PHR readiness
1.1 Use of technology		1
1.2 Usage intentions	1
1.3 Participation in design of PHRs	1	1
2 Initial registration			2
3 Initial use
4 Continued use	1
5 PHR benefits
Investigation type:
A Collection of data from PHR users, or non-participants	2	1	2
B An observational study using demographic data and records of users and non-users
C Attitudes and opinions of patients about barriers	1	1