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Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy [email protected] (716) 759-6692 (C) 2001. All rights reserved

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Page 1: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Research Protocol vs. Research Practice: Case

StudiesRichard T. Hull, Ph.D.

Professor Emeritus

Department of [email protected]

(716) 759-6692

(C) 2001. All rights reserved

Page 2: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

A talk given at the Center for Tomorrow, April 26, 2001

at the

Protection of Human Subjects Workshop

Page 3: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Introduction

Institutional Review Boards have as their chief, if not sole, role the protection of human subjects.

Traditionally, this function has rested on overseeing the design of research, recruitment of subjects, informed consent, investigation of incidents, and issues of compensation.

Page 4: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

This presentation illustrates some of the more interesting ways in which research that is well designed and well vetted by IRBs can go awry.

The aim is to draw some morals that may help sharpen IRBs’ review of research protocols and monitoring of research.

Page 5: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Equipoise: A Key Concept

A physician who recommends to a patient that the latter enroll in a research study should be in a state of

equipoise: the belief that the result of being randomized to either arm of the study poses no

greater risk to the patient than undergoing standard treatment. Otherwise, to recommend entry in a study when the physician believes another treatment is in the patient’s best interest would violate a primary

duty to the patient: to recommend the best available treatment.

Page 6: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Equipoise applies to subjects

Similarly, a subject who is enrolled in a study should believe that the state of medical knowledge is such that the known risks and benefits of being assigned to the control or to the experimental arm of the study are balanced, so that no personal risk is greater given one assignment than the other.

Page 7: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

A First Study of AZT AZT (zidovudine, retrovir, AZido-

deoxyThimidine)was the first drug to be developed to treat HIV+ individuals.

The following study sought to evaluate AZT as a potential drug to decrease the concentration of virus particles in the blood of HIV+ individuals.

It was a 2-armed, double-blind, multi-center study that used HIV+ patients as subjects.

Page 8: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

The following slides report events that have not been recorded in published

studies. The author’s representation of them is based on journalistic reporting and discussions in a variety of IRB and

educational contexts.

Page 9: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Early AZT Study Design

HIV+ Subjectsto be

randomly distributed

into 2 groups

Group #1 toreceive weeklysupply of AZT

in opaquecapsules

Group #2 to receive weekly

supply of placebo

in identical opaque

capsules

Researchers to compare

levels ofviral

particlesin blood

of thesubjects in

both groups

HIV+ particlesin AZT group

are lower

HIV+ particles

in placebo group are

higher

AND

AZT isconfirmedas a usefultreatmentfor HIV-1

relatedAIDS

IF

THEN

Page 10: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

AZT Study Results in 2 Centers

HIV+ Subjectswere randomly

distributedinto 2 groups

Group #1 received weekly

supply of AZTin opaquecapsules

Group #2 received weekly

supply of placebo in identical opaque

capsules

Researchers comparedlevels of

viralparticlesin blood

of thesubjects in

both groups

Quantity ofHIV+ particlesin AZT group

was lower

Quantity ofHIV+ particles

in placebo group was higher,

INDICATINGAZT was effective

in reducing theviral load

associated withdevelopment of

AIDS

AND

Page 11: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

AZT Study Results in 3rd Center

HIV+ Subjects

were randomly

distributed into

two groups

#1 received weekly supply

of AZTin opaquecapsules

#2 received weekly supply

of placeboin identical

opaquecapsules

Researchers comparedlevels of

viralparticlesin blood

of thesubjects in

both groups

Concentration of

HIV-1 particlesin AZT group

and in placebo

group were equal to one

another, indicating noeffect of AZTover placebo

Page 12: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Why was there differences in the data from the third center? The striking differences in results raised

the question, Why did the individuals in the trial at the third center show no difference between experimental and control groups?

Before you go on to the next slide, speculate on why such a difference might have arisen.

Page 13: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Upon Investigation

HIV+ Subjectsrandomly

assigned into two groups Group #2 gets

weeklysupply of placebo

in identical opaque

capsules

Concentrations of

HIV -1 particlesin AZT group

and in placebogroup were equal to one

another, indicating noeffect of AZTover placebo

Researchers comparedlevels of

viralparticlesin blood

of thesubjects in

both groups

Group #1 gets weekly supply

of AZT in opaque

capsules

Subjects meetafter

pickingup weeklydosage,

mixcapsules in

abowl, and

eachdraw out a

number = toweekly supply

All subjects

nowtakingsub-

clinicaldose of

AZT; groups

no longer differ

Lauritsen, 1987

Page 14: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Subjects’ Rationale

Believed AZT was only hope of survival. Each had 50/50 chance of receiving

AZT under the experimental design. By redistributing AZT and placebo, each

had 100% chance of receiving AZT, thus maximizing chance of survival.

Page 15: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Actual Effect Under original design, each subject had a

50/50 chance of receiving (what was believed to be) a clinically effective dose of AZT.

Under subjects’ “redesign”, no subject would receive what was believed to be a clinically effective dose of AZT.

If subjects at other centers had done likewise, AZT might well have been declared a failure.

Page 16: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Moral

An IRB must protect subjects from the effects of their own

misunderstanding; subjects must have equipoise with respect to each

arm of the experimental design.

Page 17: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Surfactant Study in Preemies Children born prematurely often suffer

from respiratory distress syndrome, due to the immature development of the lungs.

Their lungs lack normal concentrations of surfactant, a natural coating of mature lung tissue that facilitates the transport of O2 and CO2 into and out of hemoglobin in red blood cells.

Page 18: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

This study was designed to see if surfactant, administered artificially to the lungs of premature neonates, would improve survival and health upon discharge from the Neonatal Intensive Care Unit (NICU).

It was a multi-center, double-blind study with two arms: preemies who received surfactant, and preemies who received placebo saline.

Page 19: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

The following slides report events that have not been recorded in published

articles. The author’s representation of them is based on personal

communications and discussions in a variety of IRB and educational contexts.

Page 20: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Premature Infant Surfactant Study Design

Through parental consent, infants

of varying degrees

of prematurity were

to be recruited into a

trial of lungsurfactant derivedfrom fetal lambs.

Infants randomized

into two groups

Group #1to receive surfactantin NICU

Group #2to receive

saline placebo in

NICU

Groups to be

comparedas to

survivalin NICU

Group #1has a highersurvival rate

in NICU

Group #2 has a lowersurvival rate

in NICU

Surfactantconfirmed

as abeneficial

aid topreemies

AND

IF

THEN

Page 21: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Premature Infant Surfactant Study Results in 2 Centers

Through parental consent, infants

of varying degreesof prematurity were

recruited into a trial of lung

surfactant derivedfrom fetal lambs.

Infants randomized into two groups

Group #1received surfactant

in NICU

Group #2receivedsaline

placebo inNICU

Researcherscompared

groupsas to

survivalin NICU

Group #1had a highersurvival rate

in NICU

Group #2 had a lower

survival rate

in NICU

Looks likesurfactantconfirmed

as abeneficial

aid topreemies

Kwong, et al., 1985; Enhorning et al, 1985

Page 22: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Premature Infant Surfactant Study Results in 3rd Center

Through parental consent, infants

of varying degreesof prematurity were

recruited into a trial of lung

surfactant derivedfrom fetal lambs.

Infants randomized into two groups

Group #1received surfactant

in NICU

Group #2received

saline placebo in

NICU

Researcherscompared

groupsas to

survivalin NICU

Group #1had no highersurvival rate

in NICUthan did

Group #2;the same

percentagessurvived and

died withsaline placebo

as withsurfactant

Surfactantnot

confirmedas a

beneficialaid to

preemies

Shapiro et al., 1985

Page 23: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Why did the results in the third center differ from the others?

Noncompliance of subjects, the reason in the first study, couldn’t be the reason here, since neonates were passive participants.

Before going on to the next slide, hypothesize possible explanations for the difference in results from the third center involved in the trial.

Page 24: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Upon Investigation

Through parental consent, infants

of varying degrees

of prematurity were

recruited into a trial of lung

surfactant derivedfrom fetal lambs.

Infants randomized

into two groups

The most premature infants in Group #1

and Group #2

receivedsurfactant;the least

premature infants in Group #1

and Group #2 received

saline placebo

Group #1has no higher

survival ratein NICUthan did

Group #2;the same

percentagessurvived and

died withsaline

placeboas with

surfactant

Surfactantnot

confirmedas a

beneficialaid to

preemies

Groupscompare

das to

survivalin NICU

Resident inNICU foundhe could identify

surfactant and salineplacebo by

shaking vialsand seeing

which frothsup. Decided

to give surfactant tosickest kids

in both groups.

Page 25: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

The Resident’s Rationale

His primary obligation was to his patients. Surfactant offered the sickest kids a better

chance of survival than did the saline. With the design, half the sickest kids would

be deprived of their best chance of survival by receiving saline placebo.

So, surfactant should be given to the sickest.

Page 26: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

The Actual Result

Resident-as-therapist’s aims for patients at hand were realized.

Resident-as-researcher’s aims for future patients were frustrated.

If all researchers in the protocol had acted as the resident did, surfactant would have been declared ineffective.

Page 27: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Moral

An IRB must protect subjects from the effects of researchers’ confusion of roles, and

insure that researchers have equipoise with respect to each arm of the experimental

design and do not abandon equipoise and move from the research role to the

therapeutic role with subjects.

Page 28: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Breast Cancer

Strikes 100,000 women in the US annually, and several million women world-wide.

Standard treatment was the Halstead radical mastectomy, in which the entire breast, lymph nodes under the arm, and pectoral muscles underneath the breast are removed.

Page 29: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Standard treatment left women disfigured and with swelling of the upper arm and decreased movement.

A controversy arose among surgeons in the early 1970s over whether less radical surgical treatment might have equally good results expressed in terms of survival of the disease.

Bernard Fisher designed a multi-center protocol to answer this question.

Page 30: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Bernard Fisher’s Radical Mastectomy vs. Simple

Mastectomy Trial

Marquis, 1989

RADICALMASTECTOMY

PatientPool

MD askspt to

participate

MD doesn’t

ask

Pt givesinformedconsent

Pt refuses

RANDOMIZATION

SIMPLE MASTECTOMY

RADICALMASTECTOMY

Page 31: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Results of Fisher’s First Study 1765 patients were enrolled in the study. After 10 years, there was no better

disease-free survival with radical mastectomy than with simple mastectomy.

As a result, many women have been subsequently spared unnecessarily deforming surgery.

Marquis, 1989

Page 32: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Participating surgeons had equipoise; they believed, prior to the study, that there was no good reason to prefer one treatment over another.

Surgeons could thus respect their patient’s freely-given, informed consent to participate under randomization without violating any of their moral duties to patients.

Thus, the study was conducted ethically and with truly beneficial results.

Marquis, 1989

Page 33: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Fisher’s Study of Simple Mastectomy vs. Lumpectomy

Another question emerged in the 1970s, namely, whether equally good results could result in early cases of breast cancer from removal of only the tumor and a small surrounding margin of breast, with or without radiation therapy.

Fisher designed a second study to answer this question.

Marquis, 1989

Page 34: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Fisher’s Second Study

Pt w/ tumors

<4 cm

MD askspt to

participate

MD doesn’t

ask

Pt givesinformedconsent

Pt refuses

RANDOMIZATION

Lumpectomyw/ radiation

Other Treatment

Lumpectomyw/o radiation

Other treatment

Simple Mastectomy

OtherTreatment

after Marquis, 1989

Page 35: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Results of Second Study

Enrollment in the study was so slow that the study could not be completed as designed, because:

Women who were faced with the consequence of either radical mastectomy or lumpectomy being decided by a randomization device would not consent.

Page 36: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Modification of the Study

Statistician Marvin Zelen thought the reasons for poor enrollment might involve uncertainty of subjects about what treatment would result from randomization.

He suggested randomization prior to recruitment.

Page 37: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Fisher’s Third Study: a Prerandomized Clinical Trial

RANDOMIZATION

MD chooses

to participate

MD doesn’tchoose toparticipate

Lumpectomywith

radiation

Lumpectomy w/o

radiation

Simple mastectomy

Informedconsent

requested

Informedconsent

requested

Informedconsent

requested

YES

YES

YES

NO

NO

NO

Lumpectomyw/ radiation

Other Treatment

Lumpectomyw/o radiation

Other treatment

Simple Mastectomy

OtherTreatment

Pt w/ <4 cm.lump

Marquis, 1989

Page 38: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Results of Third Study A sufficient number of subjects enrolled. Study established that when both

lumpectomy groups were combined, disease-free survival after mastectomy was no better than disease-free survival after lumpectomy.

Study also established that disease-free survival after lumpectomy with radiation was better than mastectomy.

Page 39: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Why Did the Third StudySucceed in Enrolling a Sufficiently

Large Sample? The two studies are identical in terms of

known risks and benefits, so women should enroll in the third study no more frequently than in the second.

Thus, the third study ought to have had no greater enrollment unless it presented to potential participants a different characterization of the risks and benefits.

Marquis, 1989

Page 40: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Before going on to the next slide, speculate on the possible explanations of why the third study succeeded in enrolling sufficient numbers of participants, while the second study did not succeed.

Page 41: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Speculations as to the answer

No woman was confronted with choosing to participate in a trial in which she would be randomized between lumpectomy and mastectomy groups.

No physician had to approach a patient with what may seem to be a gambling device.

Page 42: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Physicians could choose to recommend participation or non-participation based on a judgment of the patient’s best interests.

Patients would feel more comfortable in consenting to be in the study because they would know what treatment they would receive before consenting to participate.

Marquis, 1989

Page 43: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Prerandomization mimics the purely therapeutic context; the physician can “assist” the patient’s decision by emphasizing the advantages of the treatment to which the patient has been assigned.

Marquis, 1989

Page 44: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Ethical Problems Physicians recommending to their patients

participation in a randomized clinical trial with two or more arms should have equipoise - should not, in their best medical judgment, believe one treatment to be better for the patient than another.

This trial, however, permitted physicians to pretend that they were recommending the treatment to which their patient had been prerandomized as in the patient’s interest over other possible treatments.

Page 45: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Patients’ have a tendency to “therapeutic misconception” (tendency to read consent forms, sign them, and still believe the treatment they are receiving was chosen for them because their doctor thought it best was not countered in this study).

So, this trial involved patients being randomized to a therapy they would view as much less desirable (because of the differing, permanent consequences for their bodies) in the absence of their physicians’ belief that the less desirable treatment offered a therapeutic advantage.

Marquis, 1989

Page 46: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Hence, genuine informed consent was not achieved, explaining why prerandomi-zation succeeded in this case: doctors violated their duties to their patients by not ensuring their under-standing that the treatment they were to receive was chosen for them by a random selection device, not by their physicians.

Page 47: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

A Paradoxical Result

This study had results that were of benefit to hundreds of thousands of women who now can choose less disfiguring surgery knowing they are not reducing their chances for survival.

Based on the failure of the comparable previous study, these results could not have been gained without violating the participants’ rights.

Page 48: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Possible Moral #1 An IRB must insure that the experimental

design does not surreptitiously violate a patient’s right to a fully-informed, freely-given informed consent through design

variations such as prerandomization, and must resist the temptation to subordinate duties to the subject to the beneficial aims

of the research.

Page 49: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Possible Moral #2 An IRB should be prepared, in cases where highly beneficial results of a study

cannot be gained in any other way, to subordinate the research’s duties to the

subject to the goals of the study by permitting such devices as

prerandomization to be employed when straightforward ethical design fails to

obtain sufficient participation.

Page 50: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

What is your choice?

Page 51: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

Moral #2 is in violation of the federally mandated principles of research, which require that the subject’s autonomy always be respected even when achieving a result of great public benefit would result from sacrificing the autonomy of an individual subject.

In an informal survey at this conference, 40% of IRB members asked which moral to draw from Fisher’s third study, chose the second moral.

Page 52: Research Protocol vs. Research Practice: Case Studies Richard T. Hull, Ph.D. Professor Emeritus Department of Philosophy rthull@acsu.buffalo.edu (716)

References

G. Enhorning, A. Shennan, F. Possmayer, M. Dunn, C. P. Chen, & J. Milligan. 1985. “Prevention of neonatal respiratory distress syndrome by tracheal instillation of surfactant: a randomized clinical trial. ” Pediatrics 76 (2): 145-153.

B. Fisher, Madeline Bauer, Richard Margolese, et al. 1985a. “Five-year results of a randomized clinical trial comparing total mastectomy and segmental mastectomy with or without radiation in the treatment of breast cancer.” New England Journal of Medicine 312 (11), 674-681.

B. Fisher, Carol Redmond, Edwin R. Fisher, et al. 1985b. “Ten-year results of a randomized trial comparing radical mastectomy and total mastectomy with or without radiation.” New England Journal of Medicine 312 (11), 674-681.

M. S. Kwong, E. A. Egan, R. H. Notter & D. L. Shapiro. 1985. “Double-blind clincial trial of calf lung surfactant extract forthe prevention of hyaline membrane disease in extremely premature infants. ” Pediatrics 76 (4): 5895-592.

J. Lauritsen. 1987. “AZT on trial.” New York Native, 19 October, paragraph 31. [http://www.virusmyth.com/aids/data/jltrial.htm]

D. Marquis. 1989. “An Ethical Problem Concerning Recent Therapeutic Research on Breast Cancer.” Hypatia 4 (2), 140-155.

D. Marquis. 1986. “An argument that all prerandomized clinical trials are unethical.” Journal of Medicine and Philosophy 11 (4), 367-384.

D. Marquis. 1983. “Leaving therapy to chance: An impasse in the ethics of randomized clinical trials.” Hastings Center Report 13 (4), 40-47.

D. L. Shapiro, R. H. Notter, F. C. Morin 3rd, K. S. Deluga, L. M. Golub, R. A. Sinkin, K. I. Weiss, & C. Cox. “Double-blind, randomized trial of a calf lung surfactant extract administered at birth to very premature infants for prevention of respiratory distress syndrome. ”Pediatrics 76 (4): 593-599.

M. Zelen. 1977. “Statistical options in clinical trials.” Seminars in Oncology 4 (2), 441-446. M. Zelen. 1979. “A new design for randomized trials.” New England Journal of Medicine 300 (22), 1242-

1245.