There are few good estimates of the number of individuals who manage their health data through a PHR or use a provider-sponsored web portal. It is difficult to determine the number of patients who see providers that offer patient portals; although one article pointed out that the potential reach is not insubstantial because some of the early adapters of patient portals—like the VA and Kaiser Permanente—have large patient rolls.
Even among patients who see providers with portals, the extent to which individuals decide to take advantage of them and log on to the system varies widely. Two provider organizations boasted enrollment or login rates of around 50% of their total patient population. However, results from two other providers had penetration rates hovering around 10%. This type of disparity may reflect, in part, the fact that some practitioners advocate use of the web resources more than others do. It has been estimated that between 15-20% of patients who have the option to access a PHR through their health plan will decide to sign up.
It is important to note that merely signing up for a portal does not necessarily translate into using it. One provider estimated that nearly one-third (31%) of individuals who sign up for an account on its portal actually activate the account. Among those who do login, another one-half do not make a request or otherwise communicate with providers. A study of one portal provides insight on which aspects of the site are most popular. The most common use is reviewing medical test results (54 out of every 1,000 patients enrolled in the site), followed by medication refills (44 of 1,000), summaries of office visits (32 of 1,000), and clinical messaging with providers (31 of 1,000). These numbers may appear low, but some patients may not have had a need to use those resources in the period studied. For example, looking only at individuals who actually had taken a lab test and are enrolled in the portal, one expert estimated that more than 90% of individuals reviewed the test result.
It is more difficult to find data on PHR use in the population as a whole, yet most studies suggest that it is very limited. An online survey conducted in 2003 found that only 1.5% of respondents said they use a computer to manage their health records, with an additional 0.5% saying they go online to do so. (The same survey found that almost three-quarters of respondents would be interested in using a least one of the features of PHRs.) In 2005, two experts in the field estimated that fewer than 1% of Americans are using fully functional PHRs. A 2007 survey estimated that 4% of the population uses a PHR in some form.