Variable Operationalization for the Data Management Plan - Unit 2
Quiz 2 CCIFP UPDATED ACTUAL Questions and CORRECT Answers
What is a variable? A variable is a column in a spreadsheet that is assigned to a particular attribute
that is of interest to an investigator for a research study.
Examples of 6 variables used in a diabetes-related study: age, gender, history of
diabetes, number of years with diabetes, use of insulin, use of metformin
What are data codes? Data codes are used to specify the variable attribute of study participants
Examples: Age: actual age; gender: 1 for female, 2 for male; history of diabetes: 1
for yes, 2 for no
What is a continuous variable? Quantify an attribute that can take on all possible numerical values in an interval,
in theory (usually, between a minimum and a maximum)
continuous variables example
What is a categorical variable? can take on certain values from a well-defined set or within a specific range
examples: Race/Ethnicity (1 to 7) Education Level (1 to 5)
categorical variable examples
What is a Dichotomous variables Dichotomous variable (dummy, binary, indicator variable)
can only be 1 (true) or 0 (false)
example: female: 1 if female, 0 otherwise; white: 1 if white, 0 otherwise
What is a Dataset spreadsheets with columns that specify variables and rows with codes that
describe cases (or study participants)
What is a cross-sectional dataset consist of observations of a sample of individuals, households, firms, states,
countries, etc. taken at one given point in time (Ex: NHANES database)
What is a Panel or longitudinal dataset consists of more than one observation of the same sample of individuals,
households, firms, states, countries, etc. taken at different points in time (waves)
Quiz 2 CCIFP UPDATED ACTUAL Questions and CORRECT Answers
What is a variable? A variable is a column in a spreadsheet that is assigned to a particular attribute
that is of interest to an investigator for a research study.
Examples of 6 variables used in a diabetes-related study: age, gender, history of
diabetes, number of years with diabetes, use of insulin, use of metformin
What are data codes? Data codes are used to specify the variable attribute of study participants
Examples: Age: actual age; gender: 1 for female, 2 for male; history of diabetes: 1
for yes, 2 for no
What is a continuous variable? Quantify an attribute that can take on all possible numerical values in an interval,
in theory (usually, between a minimum and a maximum)
continuous variables example
What is a categorical variable? can take on certain values from a well-defined set or within a specific range
examples: Race/Ethnicity (1 to 7) Education Level (1 to 5)
categorical variable examples
What is a Dichotomous variables Dichotomous variable (dummy, binary, indicator variable)
can only be 1 (true) or 0 (false)
example: female: 1 if female, 0 otherwise; white: 1 if white, 0 otherwise
What is a Dataset spreadsheets with columns that specify variables and rows with codes that
describe cases (or study participants)
What is a cross-sectional dataset consist of observations of a sample of individuals, households, firms, states,
countries, etc. taken at one given point in time (Ex: NHANES database)
What is a Panel or longitudinal dataset consists of more than one observation of the same sample of individuals,
households, firms, states, countries, etc. taken at different points in time (waves)
