2 Review of Last Time: Artificial Heart First artificial heart implanted in 1969No more human trials until the 1980sAbioCOR – 1st fully implantable artificial heart
3 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 differencep-value = probability of making type I errorType II Error: (False Negative)Mistakenly conclude that there is not a difference between the two, when in reality there is a differenceBeta = probability of making type II error
4 Review of Last Time: Optimal Sample Size Sample size calculationsEnsure differences between treatment & control group are realChoose our sample size:Acceptable likelihood of Type I or II errorEnough $$ to carry out the trial
6 Science of Understanding Disease EmergingHealth TechnologiesBioengineeringPreclinical TestingEthics of researchClinical TrialsAdoption & DiffusionAbandoned due to:poor performancesafety concernsethical concernslegal issuessocial issueseconomic issuesCost-Effectiveness
7 IntroductionSharing of Technology isn’t as simple as merely transplanting Technology from place to placeTechnology is a system- many components required to make it work, resources vary from country to countryTechnology needs support of human beings who understand its workings; may vary from country to country
8 Diffusion is historically slow…. 1497:Vasco Da Gama lost 100 out of 160 crew members to scurvy sailing around Cape of Good Hope1601:British Navy Captain James Lancaster was in command of 4 ships traveling from England to IndiaRequired sailors to take 3 tsp of lemon juice daily on 1 shipThe other 3 ships served as the controlResults:110/278 sailors died in control group0 deaths in the experimental group1747:British Navy Physician James Lind repeated study with similar results1865: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
9 Characteristics of people who adopt change InnovatorsMavericks, “willing to leave the village”, weird, incautious, socially disconnected, risk takersEarly AdoptersWell connected, social opinion leaders, watched by communitiesEarly MajorityLocal in perspective, follow the lead of the early adoptersLate MajorityWatch for local proofLaggardsTraditional, prefer the “tried and true”, archivistsTipping Point – often between 15% - 20% adoption; spread becomes difficult to stop.Berwick, Donald M., Disseminating Innovations in Health Care. JAMA April 16, 2003 – Vol 289, No. 15
10 Cholecystectomy: Removal of the Gall Bladder A Case StudyCholecystectomy: Removal of the Gall Bladder
12 The Gall Bladder Function: Gallstones: Stores bile made by liver After eating:Gall bladder contractsSecretes bile into duct which empties into small intestineAids in digestionGallstones:Liquid bile may precipitate into solid stonesCommon:1/5 of North Americans and ¼ Europeans develop gallstones at some point
13 Gallstones Symptoms If gallstones block outflow of bile: Abdominal discomfortPainHeartburnIndigestionAcute inflammation
14 Treatment of Gallstones Before 1990:Open surgery to remove the gall bladderEffectiveLow mortality rate ( %)7 day hospital stay30 days lost time from workMost common non-obstetric surgical procedure in many countries
15 A Case Study: Laparoscopic Cholecystectomy Most significant major surgical advance of the 1980sAllows shorter hospitalizationRapid recoveryEarly return to workSignificant financial savingsForerunner of new era of minimally invasive surgery
16 Laparoscopic Removal of Gall Bladder Patient receives general anesthesiaSmall incision is made at navel and thin tube carrying video camera is insertedSurgeon inflates abdomen with carbon dioxideTwo 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 & stonesGallbladder 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
18 Advantages/Disadvantages Benefits:Ease of recoveryNo incision pain as occurs with standard abdominal surgeryUp to 90% of patients go home the same dayWithin several days, normal activities can be resumedNo scar on the abdomenComplications:Complication rate is about the same for this procedure as for standard gallbladder surgery:Nausea and vomiting may occur after the surgeryInjury to the bile ducts, blood vessels, or intestine can occur, requiring corrective surgery5 to 10% of cases, the gallbladder cannot be safely removed by laparoscopy. Standard open abdominal surgery is then immediately performed.
20 An Important Innovator Kurt Semm ( )Gynecologist80 medical device inventionsElectronic insufflatorThermocoagulationLoop ligatorLaparoscopic suturingBrother and father owned a medical instrument company which rapidly produced instruments for himAllowed more complex procedures to be performed endoscopicallyGynecologyGeneral surgery
21 Laparoscopic Appendectomy 1985:Semm’s techniques used to perform the world’s first laparoscopic appendectomySaid to reduce problem of adhesions formed during opens surgeries
22 Public Response “He’s gone absolutely crazy.” Was asked to undergo a brain scan by his colleaguesLectures were initially greeted with laughter and derisionTechnique was initially viewed as too expensive and too dangerousSemm exaggerated problems of adhesionsSurgeons saw no reason to change a well established working method into a complex technical manner
23 Public Response Semm: Gynecologists have “surgeon envy” “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”
27 DiffusionNo technique in modern times has become so popular as rapidly as laparoscopic cholecystectomySemmDisplayed an ability to push his ideas through despite skepticism and suspicionWithout Semm, the laparoscopic revolution may have been postponed by many years
28 Diffusion of Lap CholyDiffusion of laparoscopic cholecystectomy in health care is unprecedentedSince its introduction in 1989:the laparoscopic procedure has rapidly become the most widely used treatment for gallstone diseaseBy 1992:laparoscopic cholecystectomy accounted for 50% of all cholecystectomies in Medicare populations75% to 80% of all cholecystectomies in younger populationsIncreased overall rate of cholecystectomy
29 Take Home Messages In most settings: Rate of cholecystectomy increased dramatically after introduction of the laparoscopic procedureFinancial incentives for physicians and hospitals to use the procedure influenced the rate of diffusionIntroduction of laparoscopic cholecystectomy:Associated with a 22% decrease in the operative mortality rate for cholecystectomy
30 Using Gold to Detect Cancer How long do you think it will be before we can test this in patients?NormalAbnormal
31 Using Gold to Feel Better How long do you think it will be before we can test this in patients?
32 International Diffusion of Technology Myth— Technology is largely result of one’s own people --> Technological NativismNo Technologically dynamic nation is autonomous from Technologies of other nations1500's— China produced most Technology's— Europe leads world in Technological advancesMany of these Technologies were the continuation of earlier advances in technology from China and elsewhere
33 U.S.: Diffusion of Technology United States— heavily dependent on Technologies of other countries since its inceptionEven advances that originated in U.S. are often owed to immigrantsBakelite- (Leo Baekeland- Belgium)Television Camera- (Vladimir Zworykin- Russia)
34 "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."
35 Sharing of TechnologyTechnologies shared between countries can be used for very different purposesChina— Gun Powder— used medicinally for centuries— passed on to EuropeEurope— within short time using it for cannons and firearms
36 Technology TransferWhen Technology is transferred from one country to another, modifications are most likely required for Technology to work; Thus it isn’t the exact same TechnologyJapan 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
37 Rate of Technology Usage Equal use of Technologies can have devastating impactU.S. (pop. 290 million)-- one car/ 1.5 peopleChina (pop. 1.5 billion)-- one car/ 500 people
38 Technology brings economic empowerment? Not all countries have equal resources (human and material)Even if Technologies can be transferred the results are not always desirablePakistan— introduction of tractor— replaces worker— 40% unemployment rateWorkers migrate to cities— dire poverty results— per acre crop yields hardly increased at all.Assumption that Technologies of developed nations are essential to economic and Technological modernization of undeveloped countries is problematic
39 Lab to DiffusionIt often takes a long time for Technology to move from lab. Feasibility to commercial value:Freon refrigerants— 1 yearzipper— 27 yearsFluorescent lamp--79 yearsEconomic motive is important BUT it is still only a presumption of the likely success of a Technology
40 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
41 Summary: Factors Relative advantages over existing Technology Compatibility w/ existing values of countryEase/difficulty of understanding and applying new TechnologyEase of experimentation with new TechnologyExtent to which positive results appearPeople with knowledge of Technology are KEY to diffusion of Technology
42 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."
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