TabCAT

TabCAT (Tablet-based Cognitive Assessment Tool) is used by the UCSF Memory and Aging Center to help diagnose Alzheimer's and other forms of dementia with a series of cognitive tasks, administered on an iPad or other tablet.

TabCAT is pure HTML5, so it can, in theory, run in any modern browser, and writing new tasks requires only basic web programming skills. It uses CouchDB as both its web server and its backend to store transcripts of tasks, which can be retrieved in JSON format.

TabCAT is designed with HIPAA compliance in mind. By default, it does not store any PHI at all, though it can be configured to store limited dataset PHI (e.g. dates) or full PHI (see Configuring TabCAT, below.) Any PHI stored is always clearly tagged as such so that it can be later stripped out if need be.

TabCAT can deal with a poor or nonexistent network connection by automatically shifting into offline mode; data for tasks will be stored in the browser's local storage until the network is available again.

Installation

Dependencies

On the server side, TabCAT requires CouchDB (installation instructions). We have been running on version 1.3.0, but anything later than 1.2.0 should work.

If you don't want to host a server, Iris Couch is a good, free option.

In order to build and install TabCAT, you will need:

• node.js
• kanso
• CoffeeScript
• UglifyJS
• curl
• GNU make

Don't panic! Once you have node.js, installing kanso, coffeescript, and UglifyJS is just a matter of running:

sudo npm install -g kanso coffee-script uglify-js

If you are on a UNIX system, you probably have make (and curl) already.

On Mac OS X, make is available as part of XCode; once you have XCode installed, install Command Line Tools from the Components tab of the Downloads preferences panel.

On Windows, you'll probably want to install Cygwin.

Finally, if you want to get involved in developing TabCAT, we recommend installing coffeelint (sudo npm install -g coffeelint).

Setting up your server

The setup_couchdb.sh script will perform most of the setup needed for Couch DB.

export COUCHDB_URL=<COUCHDB-URL>
./setup_couchdb.sh

Under the hood, this script performs the following operations.

• Under the couch_httpd_auth section, sets allow_persistent_cookies to true and timeout to 3600.
• Under the uuids section, sets algorithm to random.
• Creates an admin user whose username is read from the user.
• Creates a tabcat user with a password read from the user. This password is also stored in the .tabcat_password file.
• Creates a database named tabcat. Adds the tabcat user to the admins list. Adds a user provided email to members list.
• Creates a database named tabcat-data. Adds the tabcat user to the admins list. Adds a user provided email to members list.
• Under the httpd section, sets bind_address to 0.0.0.0, so as to allow access to your server from other hosts.

You can also perform these operations from Futon.

It's probably a good idea to force users to access your server via SSL; see How to Enable SSL for further instructions.

Adding additional users

New users will have to click the "Sign Up" link in Futon, using their (lowercase) email address as their username. Once they've signed up, enable their account by going to the tabcat-data database, clicking on Security, and adding their email to the Names section of members, just like you did with your own email: ["new.user@somewhere.com", "your.email@somewhere.com"].

Installing TabCAT

cd to the root of the source directory.

Set the environment variable TABCAT_HOST to your web server's URL, with the tabcat user's credentials. That will look something like this:

export TABCAT_HOST=http://tabcat:your-password@localhost:5984

Then run make.

Configuring TabCAT

By default, TabCAT will not store any PHI at all, including dates (other than year).

To change this, add a config file /tabcat-data/config. The easiest way to create this is through CouchDB's Futon interface; go to /_utils/document.html?tabcat-data and set the new document's ID to "config". To turn on dates, add a field limitedPHI, and set it to true. This enables storing of dates.

There is also a field PHI, which if set to true, allows storing of any PHI (e.g. patient name, voice recordings). Currently, TabCAT doesn't make use of this feature, though it may in the future.

Using TabCAT

To access TabCAT, browse to /tabcat/_design/console/login.html on your server.

If you're on a iPad, click "Add to Home Screen" under the bookmarks menu (upper left), hit the home button, and re-launch the browser from the shortcut you just created. This launches TabCAT in Standalone mode (no nav bar), which is what you want for running tasks.

Then log in with your email and password. It'll prompt you for a patient code; if you're just testing things out, we recommend you use the patient code 0.

If you're on Android, the best way to get the same kind of "standalone" behavior is to install Firefox for Android. Add TabCAT to your home screen by clicking on the nav bar, the History tab, holding down on the entry for TabCAT (which should be at the top), and then choosing Add to Home Screen. Then, from Firefox, install Full Screen mobile extension and enable it from the Menu button.

If you're on a Microsoft Surface, your best bet is to launch TabCAT from the desktop in Internet Explore, and then enable Full Screen mode (F11, I think?).