Biomedical Engineering Reference
In-Depth Information
Infant
mortality
Miscarriage
Deterioration
Steady state
Failure
rate
h
(
t
)
Gestation
Maturation
Useful life
Senescence
Time (
t
)
Figure
5.6
Prototypical reliability curve with a gestation (e.g., idea) stage. The highest rate of failure,
h(t)
, occurs even before
the system, process, or equipment has been made a reality. Exclusion of people from decision making or failure to get input about
key scientific or social variables can create a high hazard.
specific connotation is sometimes called “test reliability” in that it indicates how consistent measured
values are over time, how these values compare to other measured values, and how they differ when
other tests are applied. Test reliability, like engineering reliability, is a matter of trust. As such, it is often
paired with test validity; that is, just how near to the true value (as indicated by some type of known
standard) the measured value is. The less reliable and valid the results, the less confidence scientists and
engineers have in interpreting and using them. This is very important in engineering communications
generally, and risk communications specifically.
To solve problems, scientists, engineers, and decision makers need to know how reliable and valid
the data are. And, this information must be properly communicated to those potentially or actually being
affected. This includes candid and understandable ways to describe all uncertainties. Uncertainties are
ubiquitous in risk assessment. The engineer should take care not to be overly optimistic, nor overly
pessimistic about what is known and what needs to be done. Full disclosure is simply an honest rendering
of what is known and what is lacking for those listening to make informed decisions. But, remember,
a word or phrase can be taken many ways. Engineers should liken themselves to physicians writing
prescriptions. Be completely clear, otherwise confusion may result and lead to unintended, negative
consequences.
Low
Tech
Engineering
One of the differences between engineers and numerous other professions is the role of technology.
First, engineers are behind the conception and design of many emerging technologies. Second, engineers
(like medical doctors) are increasingly dependent upon technologies to do their jobs. But what exactly
is technology?
Biomedical and other engineering disciplines will continue to improve technology, giving rise to
better global health and improved health care. Sharing of technologies among nations is an ethical
obligation, especially “low-tech” solutions that can be applied in remote and rural regions of developed
countries. Such solutions need to be developed and shared with developing countries, where possible,
