Question: Comment1
The Psychology Dictionary defines sampling theory as "guidelines for taking samples which will correctly characterize the populace from which they are drawn." What does this mean? It means that a sample for a study is drawn from a population for which the test is going to be done. In nursing research, sampling is used when researchers wish to make a statement about the probability of something happening in a population. Sampling means simply studying a proportion of the population rather than the whole (Thompson, 1999). The results of a study that has assembled its sample appropriately can be more confidently applied (generalized) to the population from which the sample came. For instance, it doesn't make sense to test dialysis drugs on a patient with unrelated heart disease; you would test them on a patient with kidney disease. And since it is impossible to test that drug on every dialysis patient in the world, you would select (sample) a certain, manageable group from the universal population and test them. Then, with results of the test in hand, you can generalize that result to the rest of the universal population.
Summers writes that sampling theory describes two different types of samples: probability and nonprobability. Probability samples contain some type of randomization and consist of simple, stratified, systematic, cluster, and multistage types. Nonprobability samples lack randomization and consist of convenience or accidental, purposive, quota, volunteer, and expert types. The primary distinction between the two domains is that the probability sampling study findings can be generalized to the target population while the nonprobability sampling study findings can only be generalized to the institution where the sample was studied (Summers, 1991).
Once the results of the study are determined, the researcher can then generalize the study to the entire population based on those findings. For example, if a researcher finds in a study that a certain treatment works on 20 percent of the tested population then he or she can generalize that it would work on 20 percent of the entire (universal) population.
Comment2
When sampling comes to mind, it makes me think of walking around the supermarket on free sample day to find out which products are tasteful and which items will be purchased due to the taste test! We have preconceived notions about these products that are shown on television programs, polls, and often the public opinion around us. The sampling component is an important part of the research process that needs to be carefully studied and we need to understand the reasoning behind why we are sampling the theory. Sampling can include groups of people, events, elements and even behaviors that need to have research conducted on them.
Sampling theory examines the relations between an entire population and smaller samples drawn from within the population. This does not always involve people but can include objects, events or other elements (Grove et al., 2015). Nursing research is used to improve patient care because nursing care is guided by evidence-based practice. We have been doing much research on quantitative and qualitative research these past couple weeks and have been reading a lot about studies and how they include people and the process of the healthcare environment. Much of what we do comes from interventions that have been tested and proven safe and effective at healthcare centers all around the country and world. We are continually assessing if our interventions are appropriate and looking at ways to improve nursing care.