Biomedical Ethics
The four primary ethical principles and definition
What are:
Beneficence: do good for the pt
Non-maleficence: do no harm
Justice: everyone entitled to resources
Autonomy: right to make own decision
The four components of informed consent
What are: voluntary participation, competence, comprehension and full disclosure
What are the different types of probability sampling
Simple random sampling
Stratified random sampling ( strata)
Systematic sampling ( every nth person)
Cluster sampling ( towns or districts).
A 7-year-old boy is diagnosed with Duchenne muscular dystrophy. Neither parent is affected. The boy's maternal uncle died from complications of the same disease at age 18.
A. Autosomal dominant
B. Autosomal recessive
C. X-linked dominant
D. X-linked recessive
E. Mitochondrial
what is X linked recessive
A woman with Leber hereditary optic neuropathy has four children: two sons and two daughters. All four children inherit the disease.
Which family member is most likely to transmit the disorder to future generations?
A. One son
B. Both sons
C. Neither daughter
D. Both daughters
E. Only the oldest daughter
What is D: Both daughters
A 68-year-old man with metastatic pancreatic cancer is admitted for worsening abdominal pain and jaundice. After discussing his prognosis with his physician, he states that he wishes to discontinue chemotherapy and focus on comfort measures. His daughter insists that "everything possible" should be done and demands that the physician continue treatment.
The patient is alert, demonstrates understanding of his condition, and consistently expresses his wishes.
Which of the following ethical principles most strongly supports the physician's decision to honor the patient's request?
What is Autonomy
Protecting vulnerable individuals with diminished autonomy falls under this bioethical principle
What is Respect for persons
Investigators wish to estimate the prevalence of depression among medical students in Barbados. They obtain a complete roster of all enrolled students and use a computer-generated random number sequence to select 500 participants.
Which type of sampling
What is stratified random sampling
A woman with achondroplasia and an unaffected man have three children. Two children are affected and one is unaffected.
Which of the following best explains this inheritance pattern?
A. Autosomal recessive inheritance with complete penetrance
B. X-linked recessive inheritance
C. Autosomal dominant inheritance with a heterozygous affected parent
D. Mitochondrial inheritance
E. Genomic imprinting
what is C- Autosomal dominant inheritance with a heterozygous affected parent
Which type of study uses existing records and has already experienced both exposure and outcome when the study begins
What is restrospective cohort study
A 29-year-old woman with severe ulcerative colitis undergoes elective colectomy. Postoperatively, she develops an anastomotic leak requiring emergency reoperation. The surgeon explains that the second operation will be painful and carry substantial risks but that without intervention she will likely die from sepsis.
After discussing the risks and benefits, the patient agrees to proceed.
Which ethical principle best explains why exposing the patient to the pain and risks of another operation is ethically justified?
What is Beneficience
Four major ethical violations committed in the Tuskegee Study
What are: No informed consent, Withheld treatment, Deception and Exploitation
Investigators studying obesity among adults in the United States recognize that surveying the entire population would be impractical and expensive. They therefore select a smaller group and use the results to estimate obesity prevalence in the overall population.
Which factor most strongly determines whether the results can be generalized to the target population?
A. Sample size alone
B. Internal validity
C. Degree to which the sample represents the target population
D. Number of variables collected
E. Statistical power
What is C
Two healthy parents have a child with cystic fibrosis. They ask about the probability that their next child will also have cystic fibrosis.
Which of the following is the most appropriate response?
A. 0%
B. 25%
C. 50%
D. 75%
E. 100%
What is B: 25%
A 42-year-old woman with neurofibromatosis type 1 has numerous café-au-lait spots and several cutaneous neurofibromas. Her 18-year-old son also carries the mutation but has only two café-au-lait macules and no neurofibromas.
Which genetic phenomenon best explains the difference in disease severity between mother and son?
A. Incomplete penetrance
B. Variable expressivity
C. Anticipation
D. Locus heterogeneity
E. Genetic imprinting
What is B- variable expressivity
A 76-year-old man with poorly controlled diabetes mellitus presents for follow-up. His physician suspects that the patient's elevated hemoglobin A1c results from inconsistent insulin use. During the visit, the patient requests a newer, more expensive medication because "the insulin isn't working."
Further discussion reveals that he often skips insulin doses because he cannot afford the medication.
The physician spends time discussing lower-cost alternatives, enrollment in assistance programs, and strategies to improve adherence before considering a medication change.
Which TWO ethical principles are primarily being balanced in this situation?
What is Beneficience (acting in the patient's best interest) and Justice (fair and equitable access to care)
What is the name of the report that established ethical principles for research on human subjects
What is the system that was created to evaluate research ethics
What is the Belmont Report?
What is IRB?
Difference between cluster and stratified random
Cluster randomized: naturally occurring groups , heterogenous ( residents of coverley )
Stratified random: homogeneous grouping- all sem 1 students
A pedigree demonstrates vertical transmission involving successive generations. Both males and females are equally affected, and father-to-son transmission is observed.
Which mode of inheritance is most likely?
A. X-linked recessive
B. X-linked dominant
C. Autosomal recessive
D. Autosomal dominant
E. Mitochondrial
Investigators identify patients with lung cancer and healthy controls, then review smoking histories from medical records. They calculate an odds ratio and discover a strong association.
Final Question:
What is case control study
Because incidence cannot be directly measured in a case-control study.
Recall bias or Selection bias
A 63-year-old woman with severe osteoarthritis presents with debilitating knee pain that has not improved with physical therapy or medications. Her physician recommends total knee replacement. The physician explains that the surgery will involve significant postoperative pain and carries risks of infection and bleeding, but the likelihood of restoring mobility and improving quality of life is high.
The patient asks, "How can you recommend something that will cause me pain and might even hurt me?"
The physician explains that while treatment carries risks, physicians have an ethical obligation to avoid unnecessary or excessive harm.
What is Beneficence
Remember, nonmaleficence does not mean "never cause pain" or "never expose pt to risk"; it means avoid undue or needless harm
Ex: a pt with an opioid use disorder and hx of overdose presents with chronic back pain asking for opioids, physician opts not to prescribe medication but refers him to PT -
What is the difference between equality, equity and justice ( can explain with pictures)
Equality: everyone benefits from the same support. Equal treatment across the board
Equity: Everyone gets the support they need - ( some populations may require more help than others
Justice: Systemic plans put in place to eliminate barriers
What are the non probability sampling methods
Convenience sampling ( easily accessible)
Snowball ( refer other individuals)
Purposive or judgemental ( researchers own pick)
Quota (subdivided on specific characteristics, then non random selection)
A healthy couple has two children with Tay-Sachs disease. Neither parent has symptoms.
Which of the following is the probability that their third child will be an unaffected carrier?
A. 0%
B. 25%
C. 50%
D. 67%
E. 75%
What is C- 50%
Two unrelated patients have β-thalassemia caused by different mutations in the β-globin gene.
This is an example of:
A. Variable expressivity
B. Allelic heterogeneity
C. Locus heterogeneity
D. Anticipation
E. Penetrance
What is B- allelic heterogeneity
Different mutations in the same gene causing the same disease.
In comparison to Locus Heterogenity, where the disease is caused by mutations in different genes