COMLEX Level 2 biostats + ethics
Question and answers verified to pass
2026
Bias introduced into a study when a clinician is aware of the patient's treatment type. - correct answer
✔Observational bias
Bias introduced when screening detects a diseae earlier and thus lengthens the time from diagnosis to
death. - correct answer ✔Lead-time bias
If you want to know if geographical location affects infant mortality rate but most variation in infant
mortality is predicted by socioeconomic status, then socioeconomic status is a _____. - correct answer
✔Confounding variable/factor
The proportion of people who have the disease and test positive is known as the ___. - correct answer
✔sensitivity
Sensitive tests have few false negatives and are used to rule ___ a disease. - correct answer ✔Out (i.e.
PPD test)
Chronic diseases such as SLE. Higher prevalence or incidence? - correct answer ✔Higher prevalence
Epidemics such as influenza. Higher prevalence or incidence? - correct answer ✔Higher incidence
Incidence or prevalence: Cross-sectional study. - correct answer ✔Prevalence
Incidence or prevalence: Cohort study. - correct answer ✔Incidence and prevalence
,Incidence or prevalence: Case-control study. - correct answer ✔Neither.
A test that consistently gives identical wrong results is ___ reliability/precision and ___
validity/accuracy. - correct answer ✔high, low
An ___ ratio is an estimate of relative risk when the disease prevalence is low. - correct answer ✔Odds
What is the difference in risk in the exposed and unexposed groups called? - correct answer
✔Attributable risk
The most common cancer in men is ___. - correct answer ✔prostate cancer
Most common cause of cancer death in men is ___. - correct answer ✔lung cancer
What is the percentage of cases within 1, 2, and 3 standard deviations of the mean? - correct answer
✔68%; 95.4%; 99.7%
Birth rate is number of live births per ___ in 1 year. - correct answer ✔1000
Death rate is number of deaths per ___ in 1 year. - correct answer ✔1000
Neonatal mortality rate is the number of deaths from births to ___ days per 1000 live births in 1 year. -
correct answer ✔28
Infants mortality rate is the number of deaths from births to ___ year per 1000 live births in 1 year. -
correct answer ✔1
, Maternal mortality rate is the number of deaths during pregnancy to ___ days postpartum per 100,000
live births in 1 year. - correct answer ✔42
True or False: Once patients sign a statement giving consent, they must continue treatment. - correct
answer ✔False, patients may change their minds at any time (exceptions to the requirment of
informed consent include emergency situations and patients without decision-making capacity)
A 15 year old pregnant girl requires hospitalization for preeclampsia. Is parental consent required? -
correct answer ✔No, parental consent is not necessary for the medical treatment of pregnant minors
Can a doctor refer a patient for an MRI at a facility he/she owns? - correct answer ✔No, because
conflict of interest
Involuntary psychiatric hospitalizationcan be undertaken for which three reasons? - correct answer
✔(1) danger to self (2) danger to others (3) The patient is gravely disabled
True or False: It is more difficult to justify the withdrawal of futile care that to have withheld the
treatment in the first place. - correct answer ✔False, withdrawing a nonbeneficial treatment is
ethically similar to withholding a nonindicated one.
Can a mother can refuse to allow her child to be vaccinated? - correct answer ✔Yes (parent has the
right to refuse treatment for his/her child as long as it dose not pose a serious threat to the well-being of
the child)
Name four condition a physician refuse to continue treating a patient on the grounds of futility? -
correct answer ✔(1) There is no rationale for treatment (2) Maximal intervention is failing (3) A given
intervention has already failed (4) Treatment will not achieve the goal of care
Can a 15 year old girl seeking treatment for an STD asks that her parents not be told about her
condition? - correct answer ✔Yes (Minors can consent to care for STDs without parental consent or
knowledge)
Question and answers verified to pass
2026
Bias introduced into a study when a clinician is aware of the patient's treatment type. - correct answer
✔Observational bias
Bias introduced when screening detects a diseae earlier and thus lengthens the time from diagnosis to
death. - correct answer ✔Lead-time bias
If you want to know if geographical location affects infant mortality rate but most variation in infant
mortality is predicted by socioeconomic status, then socioeconomic status is a _____. - correct answer
✔Confounding variable/factor
The proportion of people who have the disease and test positive is known as the ___. - correct answer
✔sensitivity
Sensitive tests have few false negatives and are used to rule ___ a disease. - correct answer ✔Out (i.e.
PPD test)
Chronic diseases such as SLE. Higher prevalence or incidence? - correct answer ✔Higher prevalence
Epidemics such as influenza. Higher prevalence or incidence? - correct answer ✔Higher incidence
Incidence or prevalence: Cross-sectional study. - correct answer ✔Prevalence
Incidence or prevalence: Cohort study. - correct answer ✔Incidence and prevalence
,Incidence or prevalence: Case-control study. - correct answer ✔Neither.
A test that consistently gives identical wrong results is ___ reliability/precision and ___
validity/accuracy. - correct answer ✔high, low
An ___ ratio is an estimate of relative risk when the disease prevalence is low. - correct answer ✔Odds
What is the difference in risk in the exposed and unexposed groups called? - correct answer
✔Attributable risk
The most common cancer in men is ___. - correct answer ✔prostate cancer
Most common cause of cancer death in men is ___. - correct answer ✔lung cancer
What is the percentage of cases within 1, 2, and 3 standard deviations of the mean? - correct answer
✔68%; 95.4%; 99.7%
Birth rate is number of live births per ___ in 1 year. - correct answer ✔1000
Death rate is number of deaths per ___ in 1 year. - correct answer ✔1000
Neonatal mortality rate is the number of deaths from births to ___ days per 1000 live births in 1 year. -
correct answer ✔28
Infants mortality rate is the number of deaths from births to ___ year per 1000 live births in 1 year. -
correct answer ✔1
, Maternal mortality rate is the number of deaths during pregnancy to ___ days postpartum per 100,000
live births in 1 year. - correct answer ✔42
True or False: Once patients sign a statement giving consent, they must continue treatment. - correct
answer ✔False, patients may change their minds at any time (exceptions to the requirment of
informed consent include emergency situations and patients without decision-making capacity)
A 15 year old pregnant girl requires hospitalization for preeclampsia. Is parental consent required? -
correct answer ✔No, parental consent is not necessary for the medical treatment of pregnant minors
Can a doctor refer a patient for an MRI at a facility he/she owns? - correct answer ✔No, because
conflict of interest
Involuntary psychiatric hospitalizationcan be undertaken for which three reasons? - correct answer
✔(1) danger to self (2) danger to others (3) The patient is gravely disabled
True or False: It is more difficult to justify the withdrawal of futile care that to have withheld the
treatment in the first place. - correct answer ✔False, withdrawing a nonbeneficial treatment is
ethically similar to withholding a nonindicated one.
Can a mother can refuse to allow her child to be vaccinated? - correct answer ✔Yes (parent has the
right to refuse treatment for his/her child as long as it dose not pose a serious threat to the well-being of
the child)
Name four condition a physician refuse to continue treating a patient on the grounds of futility? -
correct answer ✔(1) There is no rationale for treatment (2) Maximal intervention is failing (3) A given
intervention has already failed (4) Treatment will not achieve the goal of care
Can a 15 year old girl seeking treatment for an STD asks that her parents not be told about her
condition? - correct answer ✔Yes (Minors can consent to care for STDs without parental consent or
knowledge)
