3: Sampling

Overview Section

 Case-Study: Effectiveness of PPH

Jaylen wants to study the effectiveness of PPH (postpartum hemorrhage) simulation on learning how to appropriately identify and use nursing interventions - and then apply the results to a population of OB staff nurses in the US. To complete this study, Jaylen needs to apply population and sampling concepts to his study. Jaylen has some decisions to make about how to conduct his study. He knows he is going to use OB staff nurses at a local hospital. He also has a pre and post survey to be administered before and after the nurses participate in simulation training. His first thought is to take a simple random sample of the nurses. However, Jaylen could divide the population into groups based on number of years of experience, and provide the simulation experience to a simple random sample from each group, thus using a stratified random sample. Alternatively he could just randomly select one team of nurses for a cluster sample. Jaylen needs to consider the advantages and disadvantages of each of these strategies, let’s see how we can help him decide.

Objectives

Upon completion of this lesson, you should be able to:

  • Identify a population versus a sample
  • Apply different techniques for drawing samples
  • Identify experimental vs observational studies
  • Identify problems in data collection that result in bias