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- Path: sparky!uunet!cs.utexas.edu!news-is-not-mail
- From: turpin@cs.utexas.edu (Russell Turpin)
- Newsgroups: sci.med
- Subject: Reliability in medicine and engineering (was: ... incomes)
- Date: 22 Dec 1992 12:51:21 -0600
- Organization: CS Dept, University of Texas at Austin
- Lines: 84
- Message-ID: <1h7o39INNehn@im4u.cs.utexas.edu>
- References: <1992Dec18.232913.11952@netcom.com>
- NNTP-Posting-Host: im4u.cs.utexas.edu
- Summary: And some comments about capitalism and medicine.
-
- -*----
- In article <BzHCq9.FFo@icon.rose.hp.com>, clw@hprnd.rose.hp.com (Carl Wuebker) writes:
- >> ... When I make a mistake, the consequence is usually time
- >> (if I'm lucky, it doesn't cost much & takes a few hours to
- >> fix). If, on the other hand, a physician makes a mistake,
- >> it can cost a life (or perhaps the quality of life) for
- >> somone. ...
-
- In article <1992Dec21.180910.12683@bnr.ca> labiche@crchh561.BNR.CA (Maurice LaBiche) writes:
- > Maybe your not as detailed a programmer as many others. Depending
- > on the type of system you work on/develop you have to handle real
- > world system faults which could shut down the computer systems
- > that control the electrical power grids or the 911/telephone service
- > in your town. These are live systems relied on by the masses in
- > normal as well as emergency situations. If these systems go out many
- > lives can be lost.
-
- Maurice LaBiche propagates a common, but wrong, perception.
- Software for which extremely high reliability is a requirement,
- such as in the control systems for an airliner, is *not*
- developed by normal programming techniques made better by better
- people, i.e., by hiring someone who is more "detailed a
- programmer." Such reliability is achieved instead by a
- qualitatively different engineering process in which the focus is
- on redundancy in both the process and the design. High
- reliability often requires redundancy between hardware and
- software, so that the hardware contains checks against software
- errors and vice versa.
-
- In this kind of engineering, it is always assumed that individual
- programmers will make mistakes, and that a program will contain
- bugs even after the programmer extensively tests it. A process
- and design is used that achieves reliability despite this fact.
- Consider, for example, the softare on the space shuttle, which
- was developed five ways by five different teams, using five
- different compilers, which runs on five different computers,
- whose decisions are arbitrated by a concensus mechanism.
-
- No life should be put at risk because a programmer makes a
- programming mistake. Any company that develops software in such
- a manner commits gross negligence. (And, yes, it will be easy to
- fill the courtroom with experts who will testify to this.) The
- programmer is likely not at fault, because most programmers are
- not learned in reliability engineering. Rather, the engineering
- managers and the company officers are at fault for deploying a
- inadequate engineering process to build a system in which high
- reliability is required.
-
- Carl Wuebker is correct that a programming mistake (or even
- programming incompetence) costs only time and money, even when
- the system under construction must function at a high level of
- reliability. Checks are built into the group engineering process
- to counter individual flubs.
-
- Medicine, unfortunately, involves some processes where individual
- human error can result in irrecoverable and tragic loss, and
- where checks against this are only indirect. The two examples
- that come immediately to mind are surgical error and emergency
- treatment error. There are indirect checks, in the sense of
- rigorous training, strict licensing, and professional accounting,
- but these do not help at the time an error is made nor do they
- provide a way to recover from the results.
-
- There are more direct checks against individual error in other
- parts of medical practice. For example, an administering nurse
- or pharmacist can stop a wildly wrong prescription before the
- patient receives it. I have the sense that tradition has impeded
- the development of more checks that would be useful, but I would
- rather have medical professionals comment on this.
-
- > Capitilism and Medicine. Live the reality. I do.
-
- Capitalism, in the sense of laissez faire markets, has next to
- nothing to do with medicine here in America. The medical
- professions are tightly regulated, the income tax code stupidly
- links medical financing to employment, insurance policies are
- dictated by state boards controlled by large insurers, hospital
- and clinic construction are state controlled, etc. ad nauseum.
- Anyone who points to American medical care as an example of
- free enterprise is living in fantasy land. We already have a
- state controlled medical industry. Other countries merely have
- *different* state controlled medical industries.
-
- Russell
-