Chapter 10: The Nuts and Bolts of correlational studies

Correlational Studies Correlational study: a type of research design that examines the relationships between multiple dependent variables, without manipulating any of the variables. The simple finding of a relationship among variables does not provide information about the causal relationship between those variables. This is the most important issue to consider when designing a correlational study. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Correlational Studies In correlational studies, researchers examine two or more measures to determine if those measures are related. Multiple measures are simply collected from a single group of subjects to determine if those measures co-vary (i.e., change together) across that group of subjects. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Correlational Studies Correlational studies can suggest the incidence or likelihood of something occurring in the presence or absence of something else. In many studies related to health, for example, correlational studies are the only options because we cannot subject someone to factors that may make them unhealthy for ethical reasons. So researchers typically must rely on correlational studies to learn about factors that influence ones health. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Correlational Studies Strong positive correlations between age and incidence of Alzheimer’s disease have been found such that by the time one reaches an age of 85, they have a 50% chance of getting Alzheimer’s disease (Alzheimer’s Association, 2011). However, few researchers would argue that age in of itself causes the disease. Instead, it is likely that factors that also are related to age cause the disease. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies Descriptive research question: a research question that asks about the presence of behavior, how frequently it is exhibited, or whether there is a relationship between different behaviors. Predictive research question: a research question that asks if one behavior can be predicted from another behavior to allow predictions of future behavior. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies Predictor variable: the dependent variable in a correlational study that is used to predict the score on another variable. Outcome variable: the dependent variable in a correlational study that is being predicted by the predictor variable. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies Regardless of the type of observational technique used to measure behavior, the goal of any correlational study is to examine relationships between two or more measures of behavior. These relationships allow researchers to better describe the behaviors being studied or predict one behavior from another behavior. Hypothesized relationships are typically tested using correlational analyses (e.g., Pearson r) or regression analyses that allow predictions. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies Despite the lack of causal information, correlational studies do provide important information about relationships between variables in cases where manipulation is not possible. Assigning participants to smoke and others not to smoke. The key to understanding correlational studies is remembering that correlation does not equal causation. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies Suppose researchers find a negative relationship between two dependent (i.e., measured) variables: number of hours of TV watched per week and grades in school for children. They cannot conclude from this result that watching more TV causes lower grades. It is possible that this causal relationship exists between these measures, but it is also possible that having lower grades causes children to watch more TV because they are not spending that time doing homework or studying. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Research Questions in Correlational Studies McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Descriptive Studies Positive relationship: a relationship between variables characterized by an increase in one variable that occurs with an increase in the other variable. Negative relationship: a relationship between variables characterized by an increase in one variable that occurs with a decrease in the other variable. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Descriptive Studies Example Campbell et al. (2007) conducted a correlational study to examine the relationship between narcissism and self-esteem because of suggestions that narcissists show high explicit self-esteem but actually have low self-esteem at an implicit level. Participants in the study completed a narcissism survey, an explicit self-esteem survey, and the Implicit Association Test. Despite suggestions about the relationship between narcissism and implicit self-esteem, scores on the narcissism survey and the IAT were not related in the study. However, narcissism scores and explicit self-esteem scores were positively correlated. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Predictive Studies For correlational studies with predictive research questions, the variable that is used for the prediction is called the predictor variable, and the variable being predicted is called the outcome variable. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.

Predictive Studies Example Paterson, Uhlin, & Anderson (2008) conducted a study that examined factors that may predict a behavior focused on working alliance. Previous studies have shown that working alliance is related to positive therapy outcomes. Therefore, a prediction of working alliance in therapy could be made based on several measures previously found to be related to this behavior. Thus, Patterson et al. examined whether clients’ preexisting expectations of counseling could predict their working alliance in a therapeutic relationship with a therapist. McBride, The Process of Research in Psychology. Third Edition © 2016 SAGE Publications, Inc.