Diffusion of Technology BIOE 301 Lecture 20. Review of Last Time: Artificial Heart First artificial...
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Transcript of Diffusion of Technology BIOE 301 Lecture 20. Review of Last Time: Artificial Heart First artificial...
Diffusion of Technology
BIOE 301
Lecture 20
Review of Last Time: Artificial
Heart First artificial heart implanted in 1969
No more human trials until the 1980s
AbioCOR – 1st fully implantable artificial heart
Review of Last Lecture: Study Design
Type I Error: (False Positive) Mistakenly conclude there is a difference between
the two groups, when in reality there is no difference
p-value = probability of making type I error
Type II Error: (False Negative) Mistakenly conclude that there is not a difference
between the two, when in reality there is a difference
Beta = probability of making type II error
Review of Last Time: Optimal Sample Size
Sample size calculations Ensure differences between treatment &
control group are real
Choose our sample size: Acceptable likelihood of Type I or II error Enough $$ to carry out the trial
Drug Eluting Stent – Sample Size
Treatment group: Receive stent
Control group: Get angioplasty
Primary Outcome: 1 year restenosis rate
Expected Outcomes: Stent: 10% Angioplasty: 45%
Error rates: p = .05 Beta = 0.2
55 patients required
Science of Understanding
Disease Emerging Health
Technologies
Preclinical Testing
Clinical Trials Adoption &
DiffusionAbandoned due to:• poor performance• safety concerns• ethical concerns• legal issues• social issues• economic issues
Bioengineering
Ethics of research
Cost-Effectiveness
Introduction Sharing of Technology isn’t as simple
as merely transplanting Technology from place to place
Technology is a system- many components required to make it work, resources vary from country to country
Technology needs support of human beings who understand its workings; may vary from country to country
Diffusion is historically slow…. 1497:
Vasco Da Gama lost 100 out of 160 crew members to scurvy sailing around Cape of Good Hope
1601: British Navy Captain James Lancaster was in command of 4
ships traveling from England to India Required sailors to take 3 tsp of lemon juice daily on 1 ship The other 3 ships served as the control
Results: 110/278 sailors died in control group 0 deaths in the experimental group
1747: British Navy Physician James Lind repeated study with
similar results 1865:
British Navy finally adopted innovation, 264 years after first recorded evidenceBerwick, Donald M., Disseminating Innovations in Health Care. JAMA April 16, 2003 – Vol 289, No. 15
Characteristics of people who adopt change
Innovators Mavericks, “willing to
leave the village”, weird, incautious, socially disconnected, risk takers
Early Adopters Well connected, social
opinion leaders, watched by communities
Early Majority Local in perspective,
follow the lead of the early adopters
Late Majority Watch for local proof
Laggards Traditional, prefer the
“tried and true”, archivists
Berwick, Donald M., Disseminating Innovations in Health Care. JAMA April 16, 2003 – Vol 289, No. 15
Tipping Point – often between 15% - 20% adoption; spread becomes difficult to stop.
A Case Study
Cholecystectomy:Removal of the Gall
Bladder
The Gall Bladder http://gensurg.co.uk/images/Biliary%20anatomy
%20-%20hsk.jpg
The Gall Bladder Function:
Stores bile made by liver After eating:
Gall bladder contracts Secretes bile into duct which empties into small intestine Aids in digestion
Gallstones: Liquid bile may precipitate into solid stones Common: 1/5 of North Americans and
¼ Europeans develop gallstones at some point
http://www.thaiclinic.com/images/
biliary_anatomy.gif
Gallstones
Symptoms If gallstones block outflow of bile:
Abdominal discomfort Pain Heartburn Indigestion Acute inflammation
http://www.qualitysurgical.com/gblad.jpg
Treatment of Gallstones
Before 1990: Open surgery to remove the gall bladder Effective Low mortality rate (0.3-1.5%) 7 day hospital stay 30 days lost time from work Most common non-obstetric surgical
procedure in many countries
A Case Study: Laparoscopic Cholecystectomy
Most significant major surgical advance of the 1980s
Allows shorter hospitalization Rapid recovery Early return to work Significant financial savings Forerunner of new era of minimally
invasive surgery
Laparoscopic Removal of Gall Bladder
Patient receives general anesthesia Small incision is made at navel and thin tube
carrying video camera is inserted Surgeon inflates abdomen with carbon dioxide Two needle-like instruments inserted; serve as
tiny hands. Pick up gallbladder & move intestines around.
Several instruments inserted to clip gallbladder artery & bile duct, to safely dissect & remove gallbladder & stones
Gallbladder is teased out of tiny navel incision. Entire procedure normally takes 30 to 60
minutes. Three puncture wounds require no stitches; may
leave very slight blemishes. Navel incision is barely visible
Laparoscopic Cholecystectomy
http://www.laparoscopy.com/pictures/lap_chol.html
http://www.lapsurgery.com/gallblad.jpg
Advantages/Disadvantages Benefits:
Ease of recovery No incision pain as occurs with standard abdominal
surgery Up to 90% of patients go home the same day Within several days, normal activities can be resumed No scar on the abdomen
Complications: Complication rate is about the same for this
procedure as for standard gallbladder surgery: Nausea and vomiting may occur after the surgery Injury to the bile ducts, blood vessels, or intestine can
occur, requiring corrective surgery 5 to 10% of cases, the gallbladder cannot be
safely removed by laparoscopy. Standard open abdominal surgery is then immediately performed.
Did this technology diffuse slowly or
rapidly?
An Important Innovator Kurt Semm (1927-2003)
Gynecologist 80 medical device inventions
Electronic insufflator Thermocoagulation Loop ligator Laparoscopic suturing
Brother and father owned a medical instrument company which rapidly produced instruments for him
Allowed more complex procedures to be performed endoscopically
Gynecology General surgery
Laparoscopic Appendectomy
1985: Semm’s techniques used to perform the
world’s first laparoscopic appendectomy
Said to reduce problem of adhesions formed during opens surgeries
Public Response “He’s gone absolutely crazy.” Was asked to undergo a brain scan by
his colleagues Lectures were initially greeted with
laughter and derision Technique was initially viewed as too
expensive and too dangerous Semm exaggerated problems of
adhesions Surgeons saw no reason to change a
well established working method into a complex technical manner
Public Response
Semm: “Both surgeons and gynecologists were
angry with me. All my initial attempts to publish on laparoscopic appendectomy were refused with the comment that such nonsense does not and will never belong to general surgery.”
Gynecologists have “surgeon envy” Semm is trying to enter into general
surgery to bolster his “operation ego”
Did this technology diffuse slowly or
rapidly?
Diffusion of Lap Choly
http://www.acponline.org/journals/ecp/marapr99/
diffus.pdf
Diffusion of Lap Choly
http://www.acponline.org/journals/ecp/marapr99/diffus.pdf
Diffusion
No technique in modern times has become so popular as rapidly as laparoscopic cholecystectomy
Semm Displayed an ability to push his ideas
through despite skepticism and suspicion
Without Semm, the laparoscopic revolution may have been postponed by many years
Diffusion of Lap Choly Diffusion of laparoscopic cholecystectomy
in health care is unprecedented Since its introduction in 1989:
the laparoscopic procedure has rapidly become the most widely used treatment for gallstone disease
By 1992: laparoscopic cholecystectomy accounted for
50% of all cholecystectomies in Medicare populations
75% to 80% of all cholecystectomies in younger populations
Increased overall rate of cholecystectomy
Take Home Messages In most settings:
Rate of cholecystectomy increased dramatically after introduction of the laparoscopic procedure
Financial incentives for physicians and hospitals to use the procedure influenced the rate of diffusion
Introduction of laparoscopic cholecystectomy: Associated with a 22% decrease in the
operative mortality rate for cholecystectomy
Using Gold to Detect Cancer
B
Normal Abnormal
How long do you think it will be before we can test this in patients?
Using Gold to Feel Better http://www.alchemistsworkshop.com/ http://www.cnn.com/2002/ALLPOLITICS/10/
02/offbeat.blue.candidate/
How long do you think it will be before we can test this in patients?
http://www.amber.org/~laloca/photos/random/stanjones.jpg
International Diffusion of Technology
Myth— Technology is largely result of one’s own people --> Technological Nativism
No Technologically dynamic nation is autonomous from Technologies of other nations
1500's— China produced most Technology 1500-1700's— Europe leads world in
Technological advances Many of these Technologies were the continuation
of earlier advances in technology from China and elsewhere
U.S.: Diffusion of Technology
United States— heavily dependent on Technologies of other countries since its inception
Even advances that originated in U.S. are often owed to immigrants
Bakelite- (Leo Baekeland- Belgium) Television Camera- (
Vladimir Zworykin- Russia)
"A country (or an individual firm) that draws on technologies developed elsewhere is spared the expense of ‘reinventing the wheel.’ But making effective use of imported technologies— even if only direct copying is required— often requires a stock of indigenous skill that cannot always be easily found."
Sharing of Technology
Technologies shared between countries can be used for very different purposes
China— Gun Powder— used medicinally for centuries— passed on to Europe
Europe— within short time using it for cannons and firearms
Technology Transfer When Technology is transferred from one
country to another, modifications are most likely required for Technology to work; Thus it isn’t the exact same Technology
Japan and Steel Production— Japanese tried to apply Dutch steel production but had to make many modifications.
The special characteristics of Japanese coal and iron ore required special modifications
Rate of Technology Usage
Equal use of Technologies can have devastating impact
U.S. (pop. 290 million)-- one car/ 1.5 people
China (pop. 1.5 billion)-- one car/ 500 people
Technology brings economic empowerment?
Not all countries have equal resources (human and material)
Even if Technologies can be transferred the results are not always desirable
Pakistan— introduction of tractor— replaces worker— 40% unemployment rate
Workers migrate to cities— dire poverty results— per acre crop yields hardly increased at all.
Lab to Diffusion
It often takes a long time for Technology to move from lab. Feasibility to commercial value:
Freon refrigerants— 1 year zipper— 27 years Fluorescent lamp--79 years
Summary: The “Not Invented Here” (NIH)
Syndrome
Risky nature of Technological innovation blocks the diffusion of new Technologies
"The status quo is a hell of a lot easier than making changes." Henry Ford
Summary: Factors Relative advantages over existing
Technology Compatibility w/ existing values of
country Ease/difficulty of understanding and
applying new Technology Ease of experimentation with new
Technology Extent to which positive results appear People with knowledge of Technology
are KEY to diffusion of Technology
Read and Reflect
“…Experts are in a position to influence the course of technological change, but at the same time, they face many difficulties in converting their knowledge into power. Having the correct technical answers isn’t enough; wielding power requires the mobilization of a constituency and the ability to create a broad base of support."