How to explain Rules and RuleFlow to your Boss

by Paul Browne

A warning if anybody asks you about your job: the words 'grabbing people's brains and shoving them into a PC' is not the best explanation. I wouldn't recommend explaining Rules and RuleFlow to your boss in those terms either. Unless they already think you're some sort of Frankenstein and your name is Igor.

A better way might be to use the workflow example from the recent Irish Java Technologies conference. It show what Rules and Ruleflow are, in a way that even your boss can understand. And if your boss is the pointy-haired-dilbert-type, they don't even need a computer to understand it.

The Health services in Bangladesh (like in many countries) can't get enough doctors. Training more is not a solution ; those that do qualify often leave for better pay elsewhere. Given the desparate need for trained medical staff in rural areas, what are health workers to do?

The solution that the Health workers came up with was IMCI - or Integrated Management of Childhood Illness. It takes what the Knowledge in Doctor's head's and captures it as a simple guide that health workers can follow. When a sick child is brought into the remote clinic the health worker is able to follow the simple step-by-step instructions (like the to make quite a sophisticated diagnosis.

I've no medical training beyond simple CPR (and if you're relying on that then you're in real trouble) but even I can understand it.

imci.jpg

Look at the pale blue box in the diagram above. It's a set of medical rules: Are there any danger signs? What are the main symptoms? What combination of these symptoms are there? What is the age of the child? How long have they been ill? Depending on the outcome of the rules, go to the next set (the pink / yellow /green) boxes and apply the rules that you find there.

That's Rules and RuleFlow.

  • Rules are 'when something is present , then do this'. And not just single rules, but many of them. Together, loads of simple rules allow you to come up with quite a sophisticated diagnosis.

  • Ruleflow allows you to group your rules. If you're a health worker with a sick child you want to do the most important checks first. Depending on the outcome, you then apply the next set of medical rules: Pink if they need urgent referral to the hospital, yellow if the clinic can cope , or green if the child can be looked after at home.


As gory as it sounds, everybody, including the doctors, are happy that their 'brains have been put into a PC' (or in this case , a set of paper cards). The Doctors are happy because they can (guilt free) move to better paying jobs. The medical workers using the system are happy because they can help the sick children that they see every day. And the children gain because the better availability of medical knowledge (via Rules and RuleFlow) is literally the difference between life and death.

This article was orginally published on the JBoss Drools Blog. Paul also writes on People and Technology, explaining Enterprise Java using Pigeons.