Watoto

An interactive medical calculator implementing Kenyan basic paediatric protocols

Designed for use by trained medical staff; Watoto supports Kenyan clinicians to assess nutritional status, approximate certain anatomical attributes and calculate essential drug dosing for paediatric patients; quickly and easily, whilst helping to reduce the likelihood of human error.

Available for Android devices via the Google Play Store (iOS having Apple review issues), the source code is published openly on GitHub to allow for contributions and transparency.

Copyright © 2016 Mat Johns et al

http://watoto.cyberfish.org

Background

Built on-top of Facebook's fanstastic React-Native framework; and has been designed with a common code base for both Android and iOS. NPM is used both as a package manager plus build (setup) and test runner.

The app was developed in Kenya by UK volunteers and local doctors as a project of the RCPCH¹ Global Links programme in partnership with the KPA²; with grateful thanks to THET and UK Aid.

Setup

You'll need NPM and NodeJS (plus Xcode and/or Android Studio) and few other bits and piece; see React-Native's Getting Started page for more info.

From a fresh repo clone...

Install dependencies

This will download all the libraries, hence be aware is a bit bandwidth heavy.

npm install

Start development server

This spawns a local packager server that is used to allow the development builds of the app to be reloaded, avoid having to repackage the entire app for each change.

npm start

This only works on locally connected simulators (who's concept of localhost is the same); however you can adjust AppDelegate.m (for iOS) or use adb reverse (for Android) to run on locally connected physical devices.

Otherwise, ensure AppInfo.js is generated

If you aren't going to run npm start, you will need to make sure the auto-generated source and build information file is generated.

npm run prestart

Build

For Android

Via Gradle; change into the android directory and use the ./gradlew script to run various build, install and other tasks.

cd android/

# build for packager
./gradlew assembleDebug

# build APK for Play Store
./gradlew assembleRelease


# If a device is connected
adb devices
./gradlew installDebug
./gradlew installRelease

For iOS

Via Xcode; when building for development (using the packager) make sure the reference to the pre-bundled file (option 2) is commented out. Conversely if building a "release version", make sure it's not.

// jsCodeLocation = [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];

Codebase

Is split up into a number of areas...

Directories

Source/ is where all of the core application code is held

Source/Data/ is (non-UX) protocol information

Source/Data/Child/ is patient related calculators and estimators

Source/Data/Drugs/ go figure!

Source/Pages/ are the UX pages/panels

Source/UI/ are UX helper classes and fonts

Files

Source/WatotoApp.js is the main starting app file (which index.ios.js and index.android.js simply loads)

Source/Router.js defines top-level app navigation

Source/Globals.js contains app wide constansts etc

Source/Network.js is the periodic 'phone-home' networking system, that allows for (anonymous) tracking of usage and provides a mechansim for messaging users (if needed)

Source/DeepLink.js defines the support for watoto:// app deep-links, allowing other apps to launch Watoto to certain pages (more below)

Source/Developer.js contains a secret developer menu for (mainly) clearing persisted state

Source/Data/DrugRegistry.js is the list of all the configured drugs and provides the grouping registry system for navigation; drugs will not appear in the app unless added here

Source/Data/DrugUtil.js to provide common helpers for numerical and formatting functions (round, round to nearest, round with precision stepping; plus number, fraction and plural formatting etc)

Source/Data/Child.js an class modeling a child (and delegates to the calculators and estimators as needed)

Source/Pages/ChildInfo.js in effect the 'home page', for inputing and displaying patient information

Source/Page/DrugDoseInfo.js the page that displays the drug doses

Testing

The are lots of unit tests, primarily in two core areas (calculations and rendering) plus the networking stack...

Source/Data/Drugs/__tests__/ unsuprisingly a lot of test patient scenerios have been created for each drug to validate appropriate calculation

Source/Data/__tests__/DrugUtil-test.js given this has the potential to affect (pretty much) all drugs, generic testing of the provided functionality

Source/Data/__tests__/Child-test.js ensuring that the child class correct converts and calculates user input

Source/Pages/__tests__/ currently just for ChildInfo and DrugDoseInfo as these two pages render critical calculated information

Source/__tests__/Network-test.js this is the main 'persistantly stateful' area of the app, validates that state is stable (especially on change/upgrade) and the lifecycles are appropriate

Running tests

npm test

Optionally, to generate coverage report and to display individual test results

npm test -- --verbose --coverage

Also to check for potential code issues

npm run lint

Releasing

To cut a release version, before building (via Xcode and/or Gradle) to set the appropriate release version build details...

npm version X.Y.Z

This will ensure all tests and passing, set the appropriate version numbers in package.json, android/app/gradle.properties and ios/Watoto/Info.plist and version tag (vX.Y.Z) the repo.

Previous releases

Prior to publishing to GitHub, a number of beta and initial releases were cut from a private repo.

• Beta
  • 0.0.2 - e84a780
  • 0.0.3 - 58db932
  • 0.0.5 - 015cfd5
  • 0.0.6 - 80815f6
  • 0.0.9 - 2349e10
  • 1.0.6 - aa272b8
• Released
  • 1.0.2 - fd3d987
  • 1.0.4 - db979a6

Deep Linking

Another app is also being developed, there was an intension to allow them to 'deep link' between each other to allow for separated development (and release cycles) by could refer to one another.

This app registers a URL protocol handler in the follow format

watoto://[type]/[what]

Pages

The following types and whats are supported

• home or child
• settings
  • about
  • legal
  • credits
• drug
  • drug name in kebab case
  • e.g iron-fe, vitamin-k and dextrose-glucose

Arguments

You can also pass patient information as URL arguments (which in the cases of the drug pages a minimum of age and weight is required).

• age
• ageScale
  • days
  • weeks
  • months default
  • years
• gender
  • male default
  • female
• weight in kg
• height in cm
• estimateWeight
  • true, 1 or any non-zero length string
  • underweight

Examples

• Just launch the app
  • watoto://home
• Patient page
  • watoto://child?age=6&ageScale=weeks&estimateWeight=underweight
• Paracetamol for 1 year, 12,1 kg
  • watoto://drug/paracetamol?age=1&ageScale=years&weight=12.1
• Credits page
  • watoto://settings/credits

Footnotes

1. Royal College of Paediatrics and Child Health. ↩

2. Kenya Paediatric Association. ↩