A researcher is interested in determining factors that influence participation in the 'Walk at Lunch' program… collect data prior to and after… Which research method should be used?

This approach collects data at a single point in time from different participants. While it can provide insights into participation levels at one moment, it does not allow for the assessment of changes over time or the impact of the program as it lacks a before-and-after comparison.

A time-series design involves collecting data at multiple intervals over time, which may include pre-program and post-program measurements. However, it typically focuses on trends rather than direct comparisons of individual outcomes before and after an intervention, making it less suitable for the specific goal of assessing immediate program impact.

This method involves randomly assigning participants to either a treatment group or a control group to compare outcomes. While effective for determining causal relationships, it is more complex and may not fit the researcher's goal of simply measuring changes in participation before and after the program implementation.