When a scientist sits down on a research project, there are dozens of ways to accomplish it. In this section of the textbook, I'm going to introduce you to various research designs--methodologies that a researcher might use.

The most important ones, for our purposes, are as follows:

1. The definition of empirical vs. non-empirical
2. Experimental designs 
3. Synthetic designs

There are two major branches of research designs: empirical (meaning based on observation) and non-empirical (relying on information we already have). Empirical simply means "by observation." If you take a guess, offer an opinion, or write some poetry, all of those have tremendous value--but they are non-empirical. If you gather survey responses, perform an experiment, or tally specific outcomes, those would be empirical. Empirical study designs allow us to see the world through observation and are among the strongest research designs for testing our beliefs.

Here are a few examples of empirical studies:

• Empirical Study Designs:

  • Randomized Controlled Trial (RCT): This is a gold standard experimental design. Participants are randomly assigned to either a treatment group or a control group, allowing researchers to establish a cause-and-effect relationship between the treatment and its outcomes.

  • Experimental Design: This design involves manipulating one or more independent variables to observe their effects on dependent variables. It aims to establish a cause-and-effect relationship by controlling potential confounding factors. Many science experiments in classrooms are of this kind.

• • Quasi-Experimental Design: Similar to experimental design, but lacks full randomization. Researchers use naturally occurring groups or predetermined factors to create comparison groups, which may lead to limitations in establishing causation.

Synthetic research methods primarily focus on "Studies of studies." In other words, they are attempting to do more than just complete one study, they are attempting to summarize and synthesize (hence, synthetic) the research as it stands. 

• Synthetic Research Methods:
  • Literature Review: A literature review involves systematically summarizing and analyzing existing research and publications related to a specific topic. It aims to provide an overview of the current state of knowledge, identify gaps, and highlight trends or patterns. A literature review can also be an empirical study in which each study is treated as a data point.

• • Systematic Review: Similar to a meta-analysis, a systematic review involves synthesizing existing research on a particular topic. It aims to provide a comprehensive and unbiased overview of available evidence without necessarily conducting statistical analyses.

• • Meta-Analysis: Meta-analysis involves statistically combining the results of multiple independent studies on the same topic to draw overall conclusions. This method can provide a more robust and reliable understanding of the effects being studied.

And what is a research methodology?

"Research methodologies" refers to the systematic approaches, techniques, and strategies that researchers use to design, conduct, and analyze their studies. These methodologies guide the process of gathering data, drawing conclusions, and contributing new knowledge to a particular field of study. Research methodologies encompass a range of decisions and actions, including how to formulate research questions, select study participants, collect data, analyze results, and interpret findings. Different research methodologies are chosen based on the nature of the research question, the available resources, ethical considerations, and the desired level of depth and rigor in the study. Common research methodologies include experimental design, qualitative research, quantitative research, case studies, surveys, content analysis, and more.

Other research designs are very helpful, so I've included them below.

• Descriptive study designs:

  • Observational Study: (Sometimes known as a descriptive study.) In this design, researchers observe and analyze subjects without intervening or manipulating any variables. It's often used when ethical or practical constraints prevent direct manipulation of variables.

  • Correlational Study: Correlational studies assess the strength and direction of relationships between two or more variables. However, they do not establish causation, only associations.

  • Qualitative Research: Qualitative research focuses on understanding the underlying meanings, motivations, and experiences of participants. It often involves methods like interviews, observations, and content analysis to gather rich and detailed insights.

• • Mixed Methods Research: This design combines both qualitative and quantitative research methods within a single study. It can provide a more comprehensive understanding of a research question by examining both numerical data and qualitative insights.

• • Case Study: In a case study, researchers deeply investigate a single individual, group, organization, or phenomenon. This approach is particularly useful for exploring complex or unique situations in depth.

• Time-based study designs:

  • Cross-Sectional Study: In a cross-sectional study, data is collected from different groups or individuals at a single point in time. It provides a snapshot of a population's characteristics and can identify associations between variables.

  • Cohort Study: Cohort studies track a specific group (cohort) of individuals with common characteristics over time. Researchers can analyze how certain variables affect the group's outcomes.

• • Longitudinal Study: Longitudinal studies follow the same group of participants over an extended period. This design allows researchers to observe changes and developments over time and assess causal relationships more effectively.

Non-empirical research designs:

• Theoretical Study: In a theoretical study, researchers develop or extend theories based on existing literature and concepts. They may propose new frameworks, models, or conceptualizations to explain phenomena or relationships in a particular field.

• Expert Opinion: Researchers can gather insights from experts in a particular field through interviews, surveys, or consultations. Expert opinions can provide valuable insights and perspectives, especially when empirical data are limited or difficult to obtain.

• Conceptual Analysis: In this approach, researchers examine and analyze concepts, ideas, or theories without necessarily collecting new data. It involves a deep exploration of the meanings, assumptions, and implications of a particular concept.

• Philosophical Analysis: Philosophical studies delve into the fundamental questions and principles underlying a particular topic. Researchers may explore the philosophical implications of theories, concepts, or ethical considerations without conducting empirical research.

• Theoretical Synthesis: This involves combining and integrating existing theories or concepts to create a new theoretical framework or perspective. It can lead to novel insights and understandings by synthesizing ideas from different sources.

• Critical Review: Critical reviews involve evaluating and critiquing existing theories, methodologies, or approaches within a specific field. Researchers assess the strengths, weaknesses, and limitations of current paradigms.

• Historical Analysis: Researchers examine historical documents, records, or narratives to understand the development and evolution of ideas, practices, or phenomena over time.

• Policy Analysis: This approach involves evaluating and analyzing existing policies, regulations, or practices to provide recommendations for improvement or change. It can have implications for decision-making and policy development.

• Theoretical Debate: Researchers engage in theoretical debates by critically discussing and comparing different viewpoints, theories, or concepts in a particular field.

Note, again, that for this class the test will only include the following:

1. The definition of empirical vs. non-empirical
2. Experimental designs 
3. Synthetic designs

Which of the research methods allows for causation conclusions to be made? 

Literature Review

Meta-analysis

Observational Study 

Randomized Control Trial 

True or false: Correlation studies can be used to discover casual relationships 

True

False

Which of these studies would be most useful to determine if PTSD effects decrease over time?

Cross-sectional study

Longitudinal study 

Observational study 

Meta-analysis 

What does empirical study mean? 

Based in observation

Relying on previous information

Study with the best results

Guessing at what the research says