Basic Statistics for the Health
Sciences Review
Determine whether the following examples of
data are quantitative or qualitative.
quotations) - ANSWER-(a) Your college GPA. Quantitavtive
A graphical Representation of the site, age and stage distribution of the cancer
patients seen in one institution is an example of - ANSWER-Descriptive statistics
( enumeration, organization, graphic - Census)
A line graph that depicts the relative frequencies of a population by FIVE YEAR age
groups is called - ANSWER-Bar Chart nominal or ordinal data, ethnicity, gender
An epidemiologic study where researcher enrolls a group of women with breast
cancer and a group of women without the disease, and compares their past
exposure to different factors is called - ANSWER-Case Control Sudy (Retrospective
study looks backwards and examines exposures to suspected risk or protection
factors in relation to an outcome that is established at the start of the study. )
An epidemologic study where a researcher enrolls a group of healthy womn and
follows them overtime to determine development of breast cancer is called a : -
ANSWER-Prospective study (A prospective study watches for outcomes, such as the
development of a disease, during the study period and relates this to other factors
such as suspected risk or protection factor(s). The study usually involves taking a
cohort of subjects and watching them over a long period.)
A study design identifies a people exposed to a particular factor and a comparison
group that was not exposed to that factor and measures and compares the incidence
of disease in the two groups. - ANSWER-Cohort study A cohort studies are usually
but not exclusively prospective, the opposite is true for case-control studies. The
following notes relate cohort to case-control studies:outcome is measured after
exposure
yields true incidence rates and relative risks
may uncover unanticipated associations with outcome
best for common outcomes)
When a researcher draws a conclusion about a population from studying a random
sample of that population he is using: - ANSWER-Inferential Statistics (For instance,
we use inferential statistics to try to infer from the sample data what the population
might think. Or, we use inferential statistics to make judgments of the probability
that an observed difference between groups is a dependable one or one that might
have happened by chance in this study.)
,If you were conducting a study and you wanted the study sample to be
representative of the population what would be the best type of sampling method to
use? - ANSWER-Random Sampling (Random sampling is a part of the sampling
technique in which each sample has an equal probability of being chosen. )
A graph that shows the distribution of women with breast cancer by stage at
diagnosis where each segment of a circle represents the proportion of women
diagnosed at that stage is called - ANSWER-A pie chart (a type of graph in which a
circle is divided into sectors that each represent a proportion of the whole.)
A pediatric oncologist wants to know the "average" age of childhood leukemia
patients seen in our hospital over last year. You check your records for leukemia
cases and identify 7 patients with the following ages 5 3 3 6 10 2 3. What is the mode?
- ANSWER-3 ( The mode of a set of data values is the value that appears most often.
Most likely to be sampled)
Which measures of central tendency is most likely to be skewed by one unusually
large or unusually small value? - ANSWER-Mean
Variance is a measure of - ANSWER-Average distance of each value from the mean.
( variance it measures how far a set of (random) numbers are spread out from their
average valuehe variance for a population is calculated by:
Finding the mean(the average).
Subtracting the mean from each number in the data set and then squaring the result.
The results are squared to make the negatives positive. Otherwise negative numbers
would cancel out the positives in the next step. It's the distance from the mean that's
important, not positive or negative numbers.
Averaging the squared differences..)
To calculate a Standard deviation you first calculate the variance and then -
ANSWER-Take the square root
The ability of a screening test to categorize someone as negative if they do not have
the disease is called - ANSWER-Specificity
To convert any normal distribution to a standard normal distribution you must
convert the values to - ANSWER-Convert to Z score
The proportion of people who test positive on a screening test but who actually do
not have the disease is called - ANSWER-
The ability of a diagnostic test to classify someone as positive if they have the
disease is - ANSWER-Sensitivity
, One set of values has a standard deviation of 1.6. Another set of values has a std
deviation of 6.1. Without looking at the individual values, what can you tell about
the two sets of values? - ANSWER-The second set of values has a larger range
All except which of the following are common sources of bias? - ANSWER-small
sample bias
Bias refers to random error in a study T/F - ANSWER-False
Cohort studies can be prospective or retrospective - ANSWER-True
Incidence Rate - ANSWER-New Cases
Prevalence Rate - ANSWER-proportion/ number of cases in California on Dec 31,
2012
Age-adjustment is a method used to - ANSWER-Compare rates of the disease in
populations or areas with different age distributions
All of the following are examples of the types of studies that are commonly
conducted using cancer registry data except - ANSWER-Experimental Studies
types of studies that are commonly conducted using cancer registry data - ANSWER-
Cohort Studies, Ecologic Studies, Case control sudies
Some cancer registries like the NCDB are not population based - ANSWER-True
The uses of data obtained from central cancer registries are virtually identical to how
data from hospital registries are used - ANSWER-False
Which if the following is a secondary cancer control activity? - ANSWER-Screening
mammography ( cancer control as "an integrated and coordinated approach to
reducing cancer incidence, morbidity, and mortality through prevention (primary
prevention), early detection (secondary prevention), treatment, rehabilitation, and
palliation.")
WHich of the following is not a limitation associated with using central cancer
registry data for cancer control? - ANSWER-A low cancer mortality rate in a
geographic area
Why has the interest in using central cancer registry data increased in recent years? -
ANSWER-Dara from the CR provide a framework for answering questions of external
validity
How is central Cancer Registry data different from hospital cancer registry data? -
ANSWER-Central cancer registry data can be used to accurately determine site
specific cancer rates in the population
Sciences Review
Determine whether the following examples of
data are quantitative or qualitative.
quotations) - ANSWER-(a) Your college GPA. Quantitavtive
A graphical Representation of the site, age and stage distribution of the cancer
patients seen in one institution is an example of - ANSWER-Descriptive statistics
( enumeration, organization, graphic - Census)
A line graph that depicts the relative frequencies of a population by FIVE YEAR age
groups is called - ANSWER-Bar Chart nominal or ordinal data, ethnicity, gender
An epidemiologic study where researcher enrolls a group of women with breast
cancer and a group of women without the disease, and compares their past
exposure to different factors is called - ANSWER-Case Control Sudy (Retrospective
study looks backwards and examines exposures to suspected risk or protection
factors in relation to an outcome that is established at the start of the study. )
An epidemologic study where a researcher enrolls a group of healthy womn and
follows them overtime to determine development of breast cancer is called a : -
ANSWER-Prospective study (A prospective study watches for outcomes, such as the
development of a disease, during the study period and relates this to other factors
such as suspected risk or protection factor(s). The study usually involves taking a
cohort of subjects and watching them over a long period.)
A study design identifies a people exposed to a particular factor and a comparison
group that was not exposed to that factor and measures and compares the incidence
of disease in the two groups. - ANSWER-Cohort study A cohort studies are usually
but not exclusively prospective, the opposite is true for case-control studies. The
following notes relate cohort to case-control studies:outcome is measured after
exposure
yields true incidence rates and relative risks
may uncover unanticipated associations with outcome
best for common outcomes)
When a researcher draws a conclusion about a population from studying a random
sample of that population he is using: - ANSWER-Inferential Statistics (For instance,
we use inferential statistics to try to infer from the sample data what the population
might think. Or, we use inferential statistics to make judgments of the probability
that an observed difference between groups is a dependable one or one that might
have happened by chance in this study.)
,If you were conducting a study and you wanted the study sample to be
representative of the population what would be the best type of sampling method to
use? - ANSWER-Random Sampling (Random sampling is a part of the sampling
technique in which each sample has an equal probability of being chosen. )
A graph that shows the distribution of women with breast cancer by stage at
diagnosis where each segment of a circle represents the proportion of women
diagnosed at that stage is called - ANSWER-A pie chart (a type of graph in which a
circle is divided into sectors that each represent a proportion of the whole.)
A pediatric oncologist wants to know the "average" age of childhood leukemia
patients seen in our hospital over last year. You check your records for leukemia
cases and identify 7 patients with the following ages 5 3 3 6 10 2 3. What is the mode?
- ANSWER-3 ( The mode of a set of data values is the value that appears most often.
Most likely to be sampled)
Which measures of central tendency is most likely to be skewed by one unusually
large or unusually small value? - ANSWER-Mean
Variance is a measure of - ANSWER-Average distance of each value from the mean.
( variance it measures how far a set of (random) numbers are spread out from their
average valuehe variance for a population is calculated by:
Finding the mean(the average).
Subtracting the mean from each number in the data set and then squaring the result.
The results are squared to make the negatives positive. Otherwise negative numbers
would cancel out the positives in the next step. It's the distance from the mean that's
important, not positive or negative numbers.
Averaging the squared differences..)
To calculate a Standard deviation you first calculate the variance and then -
ANSWER-Take the square root
The ability of a screening test to categorize someone as negative if they do not have
the disease is called - ANSWER-Specificity
To convert any normal distribution to a standard normal distribution you must
convert the values to - ANSWER-Convert to Z score
The proportion of people who test positive on a screening test but who actually do
not have the disease is called - ANSWER-
The ability of a diagnostic test to classify someone as positive if they have the
disease is - ANSWER-Sensitivity
, One set of values has a standard deviation of 1.6. Another set of values has a std
deviation of 6.1. Without looking at the individual values, what can you tell about
the two sets of values? - ANSWER-The second set of values has a larger range
All except which of the following are common sources of bias? - ANSWER-small
sample bias
Bias refers to random error in a study T/F - ANSWER-False
Cohort studies can be prospective or retrospective - ANSWER-True
Incidence Rate - ANSWER-New Cases
Prevalence Rate - ANSWER-proportion/ number of cases in California on Dec 31,
2012
Age-adjustment is a method used to - ANSWER-Compare rates of the disease in
populations or areas with different age distributions
All of the following are examples of the types of studies that are commonly
conducted using cancer registry data except - ANSWER-Experimental Studies
types of studies that are commonly conducted using cancer registry data - ANSWER-
Cohort Studies, Ecologic Studies, Case control sudies
Some cancer registries like the NCDB are not population based - ANSWER-True
The uses of data obtained from central cancer registries are virtually identical to how
data from hospital registries are used - ANSWER-False
Which if the following is a secondary cancer control activity? - ANSWER-Screening
mammography ( cancer control as "an integrated and coordinated approach to
reducing cancer incidence, morbidity, and mortality through prevention (primary
prevention), early detection (secondary prevention), treatment, rehabilitation, and
palliation.")
WHich of the following is not a limitation associated with using central cancer
registry data for cancer control? - ANSWER-A low cancer mortality rate in a
geographic area
Why has the interest in using central cancer registry data increased in recent years? -
ANSWER-Dara from the CR provide a framework for answering questions of external
validity
How is central Cancer Registry data different from hospital cancer registry data? -
ANSWER-Central cancer registry data can be used to accurately determine site
specific cancer rates in the population
