Understanding Quantitative Research Alan Glasper and Colin Rees How to Write Your Nursing Dissertation, First Edition. Alan Glasper and Colin Rees. © 2013 John Wiley & Sons, Ltd. Published 2013 by John Wiley & Sons, Ltd.

What you need to know about research Research is not a single entity; it comes in many shapes and sizes. For your dissertation you need to know something about the basic principles of research and then have access to some good research texts for specific details. The aim of this presentation, and the one on qualitative research covers some of the basic principles that will help you in assessing and writing about research studies.

Two Main Divisions Although we can put research under a number of different headings, the one that makes most sense is the division between quantitative and qualitative research designs. These two types are sometimes referred to as ‘paradigms’ as they results in different ‘world views’ of research; its purpose and how it should be conducted. Knowing the implications of these differences is a major advantage to your understanding of research.

Quantitative Research This presentation will now focus on quantitative research starting with the answer to the question – how will I know it when I see it? As it concentrates on measurement, accuracy, and relationships between variables look for tables, figures and numbers in the results section.

What type of studies are included The following are included under the heading quantitative studies: Experimental (RCTs) Quasi-experimental Case control studies Cohort studies Descriptive surveys Confirm for yourself the presence of numbers in each of these.

Why would a researcher use this approach? All the elements in a study can be traced back to the research question. That influences who will supply the data (sample), how it will be collected (tool of data collection), what ethical issues are raised in the study, and how the results will be analysed. Where the researcher is looking for answers related to quantities, measurable amounts, or the existence of statistical relationships between variables, a quantitative approach is the ideal choice.

Why concentrate on numbers and measurement? The basic ideas of quantitative research fall into the ‘scientific’ approach to research. This focuses on the collection of objective data (can be verified outside the researcher’s experience or interpretation). It also permits testing the presence of possible relationships – e.g. between giving analgesia and pain score levels. These are verified through statistical calculations, not feelings or opinions.

The importance of rigour Relationships can only be established where the researcher has followed the principles of measurement; has used accurate measuring tools and has considered the influence of other factors that might have made a difference. In other words, we can accept the evidence if the researcher convinces us that the study has been carried out rigorously, and has taken these factors into account in the design of the study.

The importance of rigour If we can be convinced that rigour exists (revealed in the methodology section), then we can apply one of the other principles of quantitative research; the ability to generalise the results from a study to other like situations. However, we need to ensure the sample is typical of those in the general group they represent to ensure there is the minimum bias (usually shown in the results).

Evidence-based practice The more trust we can put in the results of this type of research, the more likely it will be used in evidence-based practice. The most useful form of evidence is the systematic reviews of the literature as these can indicate a highly reliable and enduring relationship between variables. It is these that can indicate ‘best practice’.

Evidence-based practice The use of quantitative research in producing this kind of conclusion makes it a popular source of evidence. It is its ability to be scrutinised carefully and checked for its accuracy and consistency that makes it stronger than qualitative research in making clinically effective decisions. However, qualitative research allows us to make different types of decisions that can be just as useful to practice.

Finally Quantitative research does have its limitations as it has to be carefully scrutinised because of the difficulty of producing high quality research. It can also not answer every kind of question important within nursing. However, when a high standard is achieved, it is one of the most respected forms of evidence available to improve nursing care.