Types of Research in Psychology (A.I.)

There are several types of research methods used in psychology, each with its own strengths and weaknesses and are appropriate for different research questions.

Experimental Research:

Experimental research is the gold standard for research in psychology. Within experimental research, there are two major categories between-group and within-group studies. Experimental research is used to study cause-and-effect relationships between variables by manipulating one variable while controlling for the effects of other variables. Researchers randomly assign participants to different conditions, manipulate an independent variable and measure the effect on a dependent variable. By controlling extraneous variables through the use of the design the researchers can make statements about the causal relationship between the independent variable and dependent variable. One major weakness of experimental research is the artificiality, often external validity (generalizability) can be a concern.

Correlational Research:

Correlational research is designed to measure the degree of relationship between two or more variables. Correlation shows only that variables are related to each other, but does not indicate causality or causation. There are three types of correlation: positive, negative, and zero. In positive correlation, two variables change together in the same direction. In negative correlation, two variables change together in opposite directions. In zero correlation, there is no relationship between the two variables. Correlational research cannot infer causality and only shows a relationship which makes it difficult to determine which variable is driving the relationship.

Observational Research:

Observational research involves the observation of behavior in natural settings. Observational research captures the natural behavior of people and is ethical and practical because it does not require the manipulation of variables or artificial laboratory environments. Naturalistic observation study refers to the observation of behavior in a natural setting without external interruption. Participant observation involves the researcher participating in the behavior being observed. Systematic observation refers to the observation of specific behaviors within a structured system that can be quantified statistically. The weakness of observational research is that the observer effect can occur, which is where the presence of the observer can change the behavior that is being studied.

Case Studies:

Case studies are intensive studies and detailed descriptions of one or more individuals who exhibit unusual behavior or mental processes. Through examining and inquiring into an individual case, case studies can illustrate ideas about general behavior and treatment. Case studies are useful for generating hypotheses and suggesting an in-depth investigation., but have low external validity and generalizability.

Survey Research:

Survey research is used to collect a large amount of data from a large group of people through questionnaires and interviews. Surveys are a cost-effective way to collect information about a large population, but the researcher should be mindful of the sampling technique to ensure accurate results. As with observational research, response bias should be considered. Response bias occurs when participants answer untruthfully, withholding information, or providing socially desirable responses.

Longitudinal Research:

Longitudinal research involves the observation and data collection of a particular group of people over an extended period of time. Longitudinal research can identify patterns of behavior and changes in behavior over time that might be missed using other methods. Data can be collected at regular intervals over an extended period or even over the lifespan of the study participants. Longitudinal research is also useful for investigating developmental changes in behavior and mental processes, such as changes in personality or cognitive development. The weakness of longitudinal research is the potential for attrition, where participants may drop out of the study over time, causing the sample size to shrink and the data to lose its representativeness.

Meta-analysis:

Meta-analysis is the quantitative synthesis of studies that have already been conducted. Researchers use meta-analysis to integrate the results of several studies to determine the overall effect of an intervention or treatment. Meta-analysis can increase the accuracy and precision of estimates of the relationship between variables and enhance the statistical power of the analysis. However, meta-analysis can be limited by the quality of the original studies included in the analysis. If included studies have significant flaws, the results of the meta-analysis may not be reliable.