In this unit, you will have the opportunity to develop seven preliminary questions that you will use to appraise and determine the quality of quantitative evidence. Not all evidence is “created alike.” Determining how to evaluate evidence will help you learn the concepts of validity and reliability, as well learn five common statistical errors in quantitative studies. For example, while the data in the study may be reliable for that particular sample, it may be not be valid to use it for your practice setting. Learning to make these types of decisions from a systematic review will be the focus of this unit.
Relate Elements of Quantitative Study Designs
In this section you will learn how to critically appraise a study design. For example, you will answer important questions such as why the study was done, what the sample size may be, and whether the variables are valid and reliable.
Seven preliminary questions used to evaluate quantitative studies
Using the seven preliminary questions you will learn to ask the following questions of the reviews you conduct:
Why was the study done?
What is the sample size?
Are the measurements valid and reliable?
How was the data analyzed?
Were there any untoward events in the study?
Do the results fit with previous research?
Does the research have specific meaning for clinical practice?
Common Statistical Errors Review
It is important to recognize common statistical errors, such as bias. You will learn how important randomly assigning participants are for study value. An important aspect of systematic reviews is recognizing potential errors and bias in research. If you do not account for this you could accept studies as evidence that have errors in their design.
Principles of Statistical Methods to Participant Sampling
Random assignment of participants is the key to being able to see a cause and effect with an intervention. Without randomization, the results could be biased with a particular group response to the study. That makes it difficult to make a cause and effect relationship. This is the foundation of randomly assigning participants to a study, understanding the difference between a control group and an intervention group.