Population - Answers A well defined set that has certain specified properties
Sampling - Answers Selection of a portion or subset of the designated population that represents the
entire population
Eligibility Criteria - Answers Those characteristics that restrict the population to a homogeneous
group
Nonprobability sampling - Answers A procedure in which elements are chosen by non-random
methods
Probability sampling - Answers - A procedure that uses some form of random selection when the
sample units are chosen
Interviews - Answers A method of data collection in which a data collector questions a subject
verbally. They may be in person or performed over the telephone, and they may consist of open-
ended or close-ended questions
Demographic Data - Answers Data that includes information that describes important characteristics
about the subjects in a study (e.g., age, gender, race, ethnicity, education, marital status)
Scale - Answers A self report inventory that provides a set of response symbols for each item. A rating
or score is assigned to each response
Existing Data - Answers Data gathered from records (e.g., medical records, care plans, hospital
records, death certificates) and databases (e.g., US Census, National Cancer Database, Minimum Data
Set for Nursing Home Resident Assessment and Care Screening)
Measurement Error - Answers The difference between what really exists and what is measured in a
given study
Reliability - Answers The consistency or constancy of a measuring instrument
Validity - Answers The determination of whether a measurement instrument actually measures what
it is purported to measure
Face Validity - Answers A type of content validity that uses an expert's opinion to judge the accuracy
of an instrument
Content Validity - Answers The degree to which the content of the measure represents the universe
of content or the domain of a given behavior
Cronbach alpha - Answers Test of internal consistency that simultaneously compares each item in a
scale to all others
Level of Significance (Alpha Level) - Answers The risk of making a type I error, set by the researcher
before the study begins
Nominal Measurement - Answers Level used to classify objects or events into categories without any
relative ranking (e.g., gender, hair color)
T Statistic - Answers Commonly used in research; it tests whether two group means are more
different than would be expected by chance. Groups may be related or independent
Null Hypothesis - Answers A statement that there is no relationship between the variables and that
any relationship observed is a function of chance or fluctuations in sampling