Biostatistics Practice Quiz
Question 1
Researchers study the relationship between interpersonal violence and health in college age women. The researchers report an OR for psychological distress among abused versus non-abused women (OR 1.37 95% CI 1.03-2.21). Based on this information, you know:
- Abused women are significantly more likely to have psychological distress.
This is a clinically significant result
In this study women who were abuse were 37 times more likely to report psychological distress.
There is no significant difference in psychological distress for abused and non-abused women
Question 2
Researchers study the relationship between interpersonal violence and health in college age women. The researchers report an OR for somatic symptoms among abused versus non-abused women (OR 1.03 95% CI 0.79-1.71). Based on this information, you know:
There is no significant difference in somatic symptoms for abused and non-abused women.
Abused women are significantly more likely to have somatic sypmtoms
This is a clinically significant result
No answer text provided.
Question 3
A study examined the relationship between having a baccalaureate degree and passing a cultural competency exam among a group of 987 randomly selected registered nurses at your hospital. The researchers report that more registered nurses with a baccalaureate degree passed the cultural competency exam (OR 1.54, 95% CI 0.98-1.79). Interpret this information.
More nurses with a baccalaureate degree passed the exam but this was not a significant difference
Nurses with a baccalaureate degree were significantly more likely to pass the exam.
98% of the nurses passed the exam and the 2% that didn’t did not have a baccalaureate degree.
- This is an example of a type II error.
Question 4
A study examined the relationship between having a baccalaureate degree and passing a cultural competency exam among a group of 87 randomly selected registered nurses at your hospital. They report an OR of 1.73 (95% CI 0.44-2.79) for passing rates among nurses with vs. without a baccalaureate degree. If the results of the study were incorrect it would be an example of:
A type II error
A type I error
Sampling bias
Sampling error
Question 5
A nurse at Lakeside hospital conducts a study that reports a when there is ice on the road the risk of traumatic injuries is higher (RR=5.3, 95% CI= 2.3-8.1). You know this measure means:
Ice on the road is a significant risk factor for traumatic injuries
It is time to buy snow tires
Ice on the road is a clinically significant risk factor for traumatic injuries
Ice on the road appears to be a risk factor but it is not significant
Question 6
An emergency room nurse at Rochester Regional Health conducts a study that reports if an emergency travel advisory is issued during a storm the risk of traumatic injuries is impacted (RR=0.89, 95% CI=0.74-0.98). You know this means:
An emergency travel advisory is a significant protective factor decreasing traumatic injuries.
An emergency travel ban means the storm is worse and traumatic injuries increase 95%
There is no relationship between an emergency travel ban and traumatic injuires
About 89% of traumatic injuries occur when an emergency travel ban is in place
Question 71 pts
Your study reports that among sexually active female patients those who do not take birth control pills (BCPs) every day are more likely to get pregnant than those who take birth control pills every day (RR=8.4, p<0.05). You know this means:
Those who don’t take BCPs each day are more than eight times as likely to get pregnant when compared to those who do take BCPs QD
The results are insignificant so you reject the null
A type I error was made
If patients do not use OCPs they will be 8x as likely to get pregnant
Question 81 pts
A study that examines the relationship between eating citrus fruit and getting cold sores finds a relative risk of 1.89 with a p value of 0.047. The results indicate:
Individuals who eat citrus fruit are significantly more likely to develop cold sores
There is not a significant relationship from eating citrus fruit and developing cold sores
Eating citrus fruit is a significant protective factor for developing a cold sore
If individuals have a cold sore and eat citrus fruit they can get better significantly faster
Question 91 pts
Within 10 days after attending a June wedding, an outbreak of cyclosporiasis occurred among attendees. Of the 83 guests and wedding party members, 79 were interviewed; 54 of the 79 met the case definition. The following two-by-two table shows consumption of wedding cake (that had raspberry filling) and illness status.
| Ill | Well | Total | ||
| Total | 54 | 25 | 79 | |
| Ate wedding cake? | Yes | 50 | 3 | 53 |
| No | 4 | 22 | 26 |
The best estimate of the association to use for these data is a/an:
Risk ratio
Food specific attack rate
Odds ratio
Rate ratio
Question 101 pts
Within 10 days after attending a June wedding, an outbreak of cyclosporiasis occurred among attendees. Of the 83 guests and wedding party members, 79 were interviewed; 54 of the 79 met the case definition. The following two-by-two table shows consumption of wedding cake (that had raspberry filling) and illness status.
| Ill | Well | Total | ||
| Total | 54 | 25 | 79 | |
| Ate wedding cake? | Yes | 50 | 3 | 53 |
| No | 4 | 22 | 26 |
Source: Ho AY, Lopez AS, Eberhart MG, et al. Outbreak of cyclosporiasis associated with imported raspberries, Philadelphia, Pennsylvania, 2000. Emerg Infect Dis
2002;l8:783–6.
The best estimate of the association between wedding cake and illness is:
6.1
7.7
91.7
94.3
Question 111 pts
You randomly select 120 healthy individuals and randomize them into a group given a daily multivitamin and a group who does not take a daily multivitamin. You follow the sample for ten years and identify all cases of pernicious anemia which develop. Which statement is true?
You can determine the Risk Ratio (or relative risk) for developing pernicious anemia from this data
You should not determine a relative risk since this is a cross sectional design
Your exposure of interest is retrospective
You can only determine the odds ratio for pernicious anemia
Question 121 pts
You conduct a study of 1,000 people and determine that 137 have a virus and test positive with your screen. Twenty one have the virus and test negative with your screen. Twenty one have the virus and test negative with your screen. What is the prevalence rate of the disease?
15.8%
13.7%
2.1%
Unable to determine because this is incidence data
Question 131 pts
If utilizing a wearable fitness tracker is a statistically significant protective factor related to weight gain, identify which of the following 95% Confidence Interval (CI) for a relative risk would be appropriate.
0.37 – 0.87
6.12-12.14
0.45-12.75
0.98-2.35
Question 14
You conduct a case control study and determine that five people with Guinea Worm were exposed to water from river A. One person with the disease had no exposure to water from river A. You also determine that ten people without the disease drank from river A and eighty-nine were healthy and did not drink from river A. Calculate the appropriate Odds ratio.
44.5
14.3
5
14.3
Question 15
- A health department investigation determines that the following during an outbreak:
| Exposure | OR | p value |
| Meatballs | 4.5 | 0.07 |
| Ice cream | 2.0 | 0.04 |
| Salad | 0.78 | 0.09 |
| Soup | 1.03 | 0.12 |
What exposure was a significant risk factor?
Just the ice cream
Meatballs and ice cream
Just the meatballs
Meatballs, ice cream and soup
Question 16
- A health department investigation determines the following after an outbreak:
| Exposure | OR | 95% CI |
| Meatballs | 4.5 | 1.25-6.74 |
| Ice cream | 2.0 | 0.98-4.71 |
| Salad | 0.78 | 0.50-1.78 |
| Soup | 1.03 | 0.23-2.94 |
What exposure was a significant risk factor?
Just the meatballs
Meatballs and ice cream
Meatballs, ice cream and soup
Just the ice cream
Question 17
Which of the following describes a prospective design that analyzes a group of individuals over time to see who develops the outcome of interest?
Cohort study
Case control study
Cross sectional study
Case report
Question 181 pts
Any time you have a significant relative risk less than 1.0 you have a(n):
Protective effect
Correlation
Carryover effect
Attributable risk
