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VISN 20 User Directory

The following reports on a VISN 20 User Directory built from the user file (200) of 8 VistAs: Anchorage [463], Boise [531], Portland [648], Roseburg [653], Puget Sound [663], Spokane [668], Walla Walla [687], White City [692]. Together they hold 915,016 distinct users using 3,390,311 user file records.

User Breakdown

The directory holds 915,016 Users. The majority are in greater than one VistA. Most have a social security number (SSN) while a much smaller number have VA’s own “security id” (secid).


The graph below shows the total number of users in each system as well as a breakdown of whether those users are unique to that system (exclusive), in some but not all systems (some) or in every (all) other systems in the directory. It’s striking how few of the users in the smaller systems - for example, Walla Walla (WWW) - are unique to them. Indeed, for WWW, most of its users appear in some or every other system.


The following shows the same information but instead of totals, each system’s representation distinguishes the percentage of its users that are unique from those that also appear elsewhere. Puget Sound, the biggest system, has the highest proportion of unique users. Clearly most users in smaller VistAs also use or have some impact on other VistAs.


User Additions over Time

The following shows Daily User Addition for the last full three months for which data is available with Mondays marked on the X-axis. As expected addition mainly happens on weekdays with holidays (1/1, 1/20 and 2/17) and weekends showing little activity. December shows less activity than the following months with a steady decline through the end of the month. As expected, Puget (PUG) adds the most users but given the disparity in system size - something that shows up in the Patient Directory Report - it is surprising how close the numbers for all systems are. This needs examination.


Here are the yearly trends using a “365 day rolling mean” starting when the directory first gets data to the latest additions. In general, additions follow system size but there’s an exception in 2019 where four of the seven have a large spike in additions and Portland exceeds Puget’s total. This is one of four times where the rate of addition changes - the others are 2002, 2006 and 2009. All need examination - they must reflect the addition of or changes to VistA applications and use.


When the data is resampled by month, it shows three subpeaks for the 2019 leap in additions. The reason for Portland’s leap above Puget also shows more clearly - though Puget has one large spike in April 2019, Portland has two, one in July and one in September. Note that the lack of any spike mirrors the flat line for smaller systems during this period in the yearly trends above.

This graph also shows (“New”) the running total of new users added. As seen above, users added to VistAs sometimes already pre-exist in other VistAs. While the new user line shadows Puget’s peak in April and Portland’s in September, it is markedly lower than the spikes for Portland and Spokane in July - this indicates that much of those spikes are existing (Puget?) users being added to these systems. This needs examination.


Finally, a simple side by side set of totals for the last five years echo’s the graphs above with Portland jumping ahead of Puget in 2019. That year, Portland added 60,000 users, twice the number of a “normal” year. Spokane, too nearly doubled its numbers while Walla Walla stayed steady with under 20,000 additions. The years prior to 2019 share the same steady pattern of addition.


VistA Clone Details

Data from 8 VistAs was parsed. The VistAs are copies of production VistAs cut on the dates given below …

# VistA Station # Clone Cut Date
1 Anchorage 463 2021-01-06
2 Boise 531 2021-05-08
3 Portland 648 2021-02-12
4 Roseburg 653 2021-05-09
5 Puget Sound 663 2021-02-16
6 Spokane 668 2021-05-10
7 Walla Walla 687 2021-04-18
8 White City 692 2021-05-08