Biostatistics, Ethics, Patient Safety, & Quality Improvement

Question 1

The nurse manager noticed during her inventory review of vaccines that doses for the combination MMRV vs. single-dose varicella + MMR were inaccurate. She noticed the vials for the combination vaccine and the single-dose varicella were color-coded different shades of blue. After review of records, she was able to identify that some patients received single-dose varicella + combination MMRV, hence additional doses of varicella vaccine. She also interviewed parents to look for symptoms that could be related to overvaccination and reported those cases to the Vaccine Adverse Event Reporting System registry. To prevent future errors, she changed the color coding for these 2 immunizations to make them noticeably different and gave further training to the staff. Another chart review a month later revealed a significant decrease in vaccine error.

What analysis method did this nurse use to find the contributing factors that led to this error?

Answer 1

Root-Cause Analysis

Root-cause analysis is a structured process used by a team to identify potential causes that led to a serious undesired outcome:

1. Incident is defined and information gathered.
2. Leader identifies team members who will investigate specific parts of the process.
3. Team meets to review and describe the event.
4. Group identifies the factors that may be contributors to the event.
5. Team analyzes the root causes to identify system issues.
6. Team designs and implements change.
7. Change is measured.

Question 2

What statistical parameter refers to how well a test correctly identifies those in a population with a given disease?

Answer 2

Sensitivity

The sensitivity of a test refers to how well it correctly identifies those who have the disease.

Sensitivity = TP/(TP + FN) = TP/(#Diseased)

Tests that are highly sensitive will have a low false-negative rate, thus they help to rule out disease.

Remember SNOUT: SeNsitive tests help rule OUT disease.

Question 3

What statistical measure helps determine the usefulness of a screening test?

Answer 3

Positive Predictive Value

The positive predictive value (PPV) of a diagnostic test is the probability of disease in a patient with a positive test. It takes into account both the number of true positives and the number of false positives. This combination reflects prevalence. The formula is:

PPV = True Positives/(True Positives + False Positives) or PPV = TP/(TP + FP)

PPV predicts the percentage of positive tests that will actually be true positives. The closer this number is to 100%, the better the test is.

Question 4

A 12-year-old girl is admitted for community-acquired pneumonia and is given a dose of ampicillin in the emergency department prior to transfer to the floor. En route she experiences anaphylaxis, which is easily reversed with a single intramuscular injection of epinephrine. She is discharged within a typical time period for inpatient treatment for pneumonia. Later investigation reveals her medication reconciliation form was not completed during triage to note her allergy to penicillin antibiotics.

Was this anaphylactic reaction a preventable or nonpreventable adverse event?

Answer 4

Preventable

One of the foremost safety goals of all health care providers is to minimize preventable harm—a modifiable cause of harm that results from medical care. Preventable harm can cause legal and psychological damage to patient and provider.

Question 5

What is the incidence of a disease?

Answer 5

The Occurrence of New Cases of a Disease Within a Specified Period of Time

It can also be seen as the probability that a person develops that disease during that period of time.

The formula is: (Total # of new cases of disease)/(Total # tested during specific time period)

Question 6

A provider sees a teenager in the clinic with fever and cough, and he is found clinically to have community-acquired pneumonia. The provider writes a prescription for penicillin but soon realizes upon chart review that this patient has an allergy (hives) to this antibiotic.

What source can the provider access to identify alternative therapy for community-acquired pneumonia in patients with penicillin allergy?

Answer 6

National Best Practice Guidelines

Providers can access national best practice guidelines related to their specialties and review sections on alternative drug choices for patients who have specified allergies. Evidence-based guidelines are created to standardize care for various conditions. They are established by members of a designated medical society or academy through consensus review of notable research.

Question 7

An 18-year-old young man sustained crush injuries to both lower extremities. At the hospital arteriography was performed, and on the imaging film the right leg was noted to be avascular, requiring amputation. Following surgery, it was discovered that the x-ray technician labeled the imaging film incorrectly and noted the left leg was avascular, not the right. This patient subsequently underwent a 2nd surgery to amputate the truly avascular extremity.

What is this type of event called in medicine?

Answer 7

A Medical Error

A medical error is a failed process that may or may not result in harm to the patient.

Question 8

Parents of a 5-year-old girl refuse treatment for her diabetic ketoacidosis due to religious beliefs.

Is the physician obligated to comply with their refusal?

Answer 8

No

The physician must provide treatment for reversible, life-threatening conditions, even if the parents disagree. Other situations in which parental consent for treatment is not necessary include emancipated minors or mature minors (≥ 14 years of age in certain states) who can provide their own informed consent.

Question 9

Autonomy is the framework for ethical reasoning in adults.

What framework is used in most pediatric cases?

Answer 9

Beneficence

Beneficence is the obligation of the practitioner to act in the best interest of the patient. Many factors must be taken into account, including the patient’s developmental capacity, the benefits/risks associated with the treatment, and input from the parents.

Question 10

What statistical tests are influenced by the prevalence of the disease?

Answer 10

Positive and Negative Predictive Values

If a disease is very prevalent, then a positive test is likely to be a true positive. If a disease is very rare, a positive test is less likely to be a true positive. Sensitivity and specificity are not influenced by the prevalence of the disease/condition but are related to the tests themselves.

Question 11

What is the prevalence of a disease?

Answer 11

Percent of People in a Population Who Have the Disease at Any Point in Time

Prevalence = # Diseased/Total in studied population

In other words, the prevalence indicates how widespread a particular disease is.

Question 12

What statistical parameter identifies how well a test rules out those in a population who do not have a given disease?

Answer 12

Specificity

Specificity = TN/(TN + FP) = TN/(#Not Diseased)

Highly specific tests convey with certainty that a positive result means the patient actually has the disease. Specific tests help rule in a disease because the false-positive rate is low.

Remember SPIN: SPecific tests help rule IN disease.

Question 13

You are consulted to evaluate a child in the intensive care unit for brain death.

How many examinations are required to determine brain death?

Answer 13

2 Separate Examinations

In the United States, children must undergo 2 separate physical examinations (including brainstem testing) before brain death can be declared. The examinations must be separated by an observation period, the length of which depends on the age of the child.

Question 14

What p value is considered statistically significant?

Answer 14

p ≤ .05

The smaller the p value, the more confident we can be that the outcome of the study is not simply a chance occurrence. For a study with a p value of .05, the likelihood that the results are due to chance is only 1 in 20 (= 5% or .05). A p value ≤ .05 is considered statistically significant, but smaller p values (such as .01 or .001) imply even greater statistical significance.

Question 15

What are the 2 main observational study designs?

Answer 15

Cohort Studies and Case-Control Studies

Observational studies attempt to correlate exposures (such as smoking) with outcomes (such as lung cancer) but do not assign patients to one group or another.

Cohort studies entail following a group of individuals prospectively over time to see which exposures cause disease (e.g., to determine if there is a causal association between thimerosal exposure in infants and developmental disorders).

Case-control studies involve comparing people with the disease to those without the disease to identify relevant risk factors (e.g., to see if there is a causal relationship between acetaminophen and Reye syndrome). Help with rare diseases.

Question 16

Currently, IV solutions are compounded in the main pharmacy once a provider places the order in the electronic medical record. Nursing staff feels there is often a delay in care to the patient, who waits for the order to be placed upon admission then compounded by pharmacy. They asked for a review of the process in ordering, identifying, and administering the IV fluids. A team of medical staff reviewed the process and suggested changes that led to improved quality care and patient safety.

What is the name of this technique for process improvement that can be applied to prevent medication error?

Answer 16

Lean and Six Sigma

The lean and six sigma methodology is often used together to make a process more effective and efficient, thereby eliminating waste and improving clinical outcome. In general, a team of health care workers meets regularly to identify potential systemic problems and establish a new process in care that reduces errors.

Question 17

A 15-year-old female is admitted from the emergency department for medical management of liver failure following an intentional ingestion of an overdose of acetaminophen. She is found dead in her bed a few hours later with a needle and syringe by her side.

What is this type of medical event called?

Answer 17

Sentinel Event

A sentinel event is an unexpected occurrence within a health care environment, unrelated to the expected course of care, resulting in death or serious physical or psychological harm to a patient. Any time a sentinel event happens, it must be investigated. After the investigation, there must be a credible plan to prevent a similar event from happening.

Question 18

The family of a child with multiple disabilities comes to your office to establish their primary pediatric care.

What multifaceted approach should you establish to meet the needs of the child and family?

Answer 18

A Medical Home

Establishing a medical home entails a multifaceted approach that includes the following:

• Understanding the patient’s condition/disabilities
• Coordinating with specialists
• Referring and/or determining eligibility for developmental and educational resources
• Coordinating advanced planning
• Helping the caregiver get necessary emotional and physical support

Question 19

What are the 2 common errors that statistical analyses attempt to prevent?

Answer 19

Type 1 Errors and Type 2 Errors

Type 1 error = concluding there is a difference between groups or outcomes (rejecting the null hypothesis) when there is not. Type 1 errors are exposed by investigating the p value (statistical significance).

Type 2 error = concluding there is no difference between groups or outcomes (accepting the null hypothesis or failing to reject the null hypothesis) when one actually exists. Type 2 errors are typically exposed by investigating the power of a study.

Question 20

At a large medical facility in a major city, registration was taking too long, according to results from patient satisfaction surveys. The staff planned an electronic registration kiosk center to assist in registering less acute patients. They implemented the process and then sought feedback. They found the process to be beneficial, but realized they needed to adjust the process for non-English-speaking patients.

This activity of planning, implementing, observing the results, and acting on or adjusting to the information gathered is an example of what method of quality improvement?

Answer 20

Plan, Do, Study, Act (PDSA)

The goal of PDSA is to perform small tests of change, analyze those results, and then make adjustments if necessary. This is the scientific method used for action-oriented learning. When the process is stable and sustainable, it is implemented on a larger scale.

Question 21

True or false?

Any information shared by an adolescent must be kept confidential.

Answer 21

False

Exceptions to confidentiality include child abuse, sexual abuse, suicidal ideation/attempt, homicidal ideation, and violent injuries. Additionally, a parent or guardian must become involved if any life-threatening behaviors are disclosed.

Question 22

The lead physician was concerned about the ages of patients being screened for streptococcal pharyngitis and the process of Streptococcus screening in the office, so he set up a performance improvement project to assess this clinical issue. The team agreed on using the guidelines for Streptococcus screening established by the American Academy of Pediatrics, and data was collected in cycles to assess the age at which testing was performed and clinical symptoms at presentation. The staff completed 3 cycles over a period of 3 months. They then analyzed the data, adjusted their practice standard, and assessed 3 more cycles, which showed lower false-negative rates of group A streptococcal (GAS) pharyngitis.

This process of data analysis and adjustment over time is best described by what term?

Answer 22

Quality Improvement

Quality improvement is systematic analysis with actionable change leading to better health outcomes.

Question 23

What is the main advantage of randomized controlled trials?

Answer 23

It reduces the risk of bias and confounding variables that can occur if patients choose or are assigned a specific treatment group.

A randomized controlled trial (RCT) is a study design in which the researcher assigns a single group of patients randomly into different study groups—an intervention vs. a control—in order to determine which treatment is better. RCTs are the gold standard of testing for new medical interventions.

Question 24

A 12-year-old patient was wheeled into the operating room (OR) to begin the time out process for his procedure. The surgeon was not yet in the room when the time out was begun by the OR coordinator. The scrub technician spoke up, advising the team to pause until the surgeon arrived. When the physician came in and the time out was restarted, the team realized this patient was mistaken for another who had a similar name. Due to this near-miss, the OR team instituted a 2-step process whereby patients are identified for surgery by the OR team while in preoperation first and then again upon transfer to the designated operating suite.

What is the importance of assessment and redesign of health care processes in either inpatient or outpatient facilities?

Answer 24

Avoid Medical Error and Maintain the Safety of Patients

Instituting processes in health care delivery and redesigning care practice to improve health outcomes can reduce the unnecessary harm that occurs yearly in health care settings. Failure modes and effects analysis (FMEA) is a process improvement tool used to identify how a process might fail and what the impact of that failure will be. FMEA is a proactive way to diagnose parts of a new or existing process that needs revision before a bad outcome occurs. The hope is to prevent a sentinel event before it happens.

Question 25

An 8-year-old boy presents to the emergency department with abdominal pain and vomiting. He has no known medication allergies. His physical examination is suggestive of appendicitis, which is confirmed by abdominal ultrasound. Preoperatively he is given an intravenous dose of cefazolin, a cephalosporin antibiotic. Shortly thereafter he develops hives and airway compromise with hypotension, which is reversed with a dose of intramuscular epinephrine.

Is this adverse event preventable or nonpreventable?

Answer 25

Nonpreventable

This is nonpreventable because the patient did not have a prior known allergy, so it is a general risk of treatment.