Chapter 7 – cross-sectional, longitudinal, and case study designs

Study design
a research strategy specifying the number of cases to be studied, the number of times data will be collected, the number of samples that will be used, and whether the researcher will try to control or manipulate the independent variable in some way
Casual hypothesis
a testable expectation about an independent variable’s effect on a dependent variable
Cross-sectional study
a study design in which data are collected for all the variables of interest using one sample at one time
Causal relationship
a non-spurious relationship between an independent and a dependent variable with the independent variable occurring before the dependent variable
Spurious relationship
a non-causal relationship between two variables
Requirements for supporting causality
include a pattern or relationship between the independent and dependent variables, determination that the independent variable occurs first, and support for the conclusion that the apparent relationship is not caused by the effect of one or more third variables
Internal validity
agreement between a study’s conclusions about causal connections and what is actually true
Longitudinal research
a research design in which data are collected at least two different times, such as a panel, trends, or cohort study
Panel study
a study design in which data are collected about one sample at least two times where the independent variable is not controlled by the researcher
Panel attrition
the loss of subjects from a study because of disinterest, death, illness, or inability to locate them
Panel conditioning
the effect of repeatedly measuring variables on members of a panel study
Trend study
a study design in which data are collected at least two times with a new sample selected from a population each time
Cohort study
a study that follows a cohort over time
Cohort
a group of people born within a given time frame or experiencing a life event, such as marriage or graduation from high school, in the same time period
Case study
a research strategy that focuses on one case (an individual, a group, an organization, and so on) within its social context at one point in time, even if that one time spans months or years