Which type of research compares two or more groups without manipulating any conditions?

The type of research that compares two or more groups without manipulating any conditions is best represented by comparative research. This approach allows researchers to investigate differences between groups based on existing factors rather than altering any variables to see how they may impact outcomes.

In comparative research, the goal is to understand how different groups behave or respond under naturally occurring conditions. This can involve examining varying populations, demographics, or other characteristics that classify the groups being studied. Because there is no intervention or manipulation by the researcher, this method seeks to draw conclusions based on the observations made from the natural variations among groups.

While correlational research examines the relationships between variables, it does not specifically focus on group comparisons in the same way. Descriptive research primarily offers a snapshot of characteristics or situations without delving into group comparisons. Ex post facto research, although it can involve comparisons post hoc (after the fact), typically looks at relationships between an independent variable that cannot be ethically or practically manipulated and its subsequent effects, which differentiates it from straightforward group comparison analysis.