What does probability sampling ensure about the selection of participants?

Probability sampling ensures that all individuals in the population have an equal chance of being selected for the study. This approach is critical because it helps to minimize selection bias, allowing researchers to generalize the findings from the sample to the broader population. By giving every member an equal probability of being included, the integrity of the sample is maintained, enabling the comparisons and conclusions drawn from the data to be more robust and trustworthy. This method enhances the validity of the research, as it supports the assumption that the sample is representative of the population.

The emphasis on random selection in probability sampling is fundamental to achieving objective results, contrasting with non-probability sampling methods, which may introduce bias and limit the extrapolation of findings. This system of selection is particularly important in evidence-informed practice, where the goal is to make decisions based on sound, representative evidence.