Malcolm Gladwell's three best-selling books are filled with fascinating examples of all sorts of things to underscore the interesting points he makes about a wide variety of topics. I'm currently readying his book "Blink," about how people make process information and make decisions in the 'blink of an eye."
The example he shares about an overcrowded hospital Emergency Room's decision making process really resonated with me. Brendan Reilly, named the chairman of Medicine at Cook's County Hospital in Chicago in 1996, was in dire need of a way to improve the conditions of the hospital when he showed up there. The Emergency Room faced extreme amounts of resource pressure in particular; there were too many patients needing care and too few doctors and beds to serve them all promptly. One of the most resource-sapping processes was the treatment of patients who entered the ER complaining of chest pains.
"From the beginning, the question of how to deal with heart attacks was front and center." About 30 people a day came into the ER "were worried that they were having a heart attack. And those thirty used more than their share of beds and nurses and doctors and stayed around a lot longer than other patients."
"Reilly's first act was to turn to the work of a cardiologist named Lee Goldman. In the 1970's, Goldman...p. 133
He... announced that he was holding a bake-off. For the first few months, the staff would use their own judgment in evaluating chest pain, the way they always had. Then they would use Goldman's algorithm, and the diagnosis and outcome of every patient treated under the two systems would be compared.
For two years, data were collected, and in the end, the result wasn't even close. Goldman's rule won hands down in two directions; it was a whopping 70 percent better than the old method at recognizing patients who weren't actually having a heart attack. at the same time, it was safer. the whole point of chest pain prediction is to make sure that patients end up having major complications are assigned right away to the coronary and intermediate units. Left to their own devices, the doctors guessed right on the most serious patients somewhere between 75 and 89 percent of the time. The algorithm guessed right more than 95 percent of the time.... He went to the ED and changed the rules."
I suspect that if you asked 100 cardiologists whether they would perform more accurate assessments that the 3 question Goldman algorithm would, you would find that all 100 of those cardiologists would feel confident in their ability to outperform the 3 question algorithm. After all, the algorithm didn't allow for subject matter expertise.
How is this Relevant to Software Testing?
When many business leaders think of software testing what they want is something that catches bugs before the product is released to the customer. To some extent this can be automated. There are many previous bugs (and experience with bugs in other software) that allow us to create specific tests which will identify known bugs.
So if we have a form on the web application, we can test various scenarios and make sure the form is processed properly: submitting the form when it should or displaying the proper error message when it should do that. It is wise to have test plans to check for these bugs.
Creating simple easy to follow guidelines to address known issues is a wise action. This is true for creating a simple checklist to use in screening for heart attacks and for creating test plans that cover the known issues.
While those are wise they are by no means sufficient. Physicians bring a great deal of expertise to evaluating patients for a huge number of symptoms. And they can use their knowledge and experience to judge where they need more evidence (for example, a diagnostic x-ray or an analysis of a blood sample) to make a judgement. And to judge is software will work as users wish simply following a test plan robotically is not sufficient. The experience and expertise of a software tester allows them to probe the software applications and spot not only bugs but weaknesses that should be addressed so users of of the software have the best experience.
The appropriate methods depend upon the need. And sometimes the expert is not as effective as simply using tools or a check sheet that has been developed specifically for that purpose. It is important to design processes in your organization to find the most effective strategies given the local circumstances.
Experimenting, by using evidence based management practices, is needed to determine what is most effective. Assuming that the best solution is always relying on the experts is not accurate (as the example Gladwell used shows). A great tool to aid in determining what practices work best is the Plan-Do-Study-Act cycle made famous by Dr. W. Edwards Deming.