1 Research: an introduction

In this chapter, you will learn to:

  • identify quantitative and qualitative research.
  • identify the steps in the quantitative research process.

1.1 How do we know what we know?

Scientists once believed that all life regularly and commonly arose spontaneously from non-living matter. Recipes even existed; for example, van Helmont (van Helmont 1671; Pasteur 1922) gave this recipe for making a mouse:

If a soiled shirt is placed in the opening of a vessel containing grains of wheat, the reaction of the leaven in the shirt with fumes from the wheat will, after approximately twenty-one days, transform the wheat into mice.

This was called 'spontaneous generation' (or 'abiogenesis'). We now know this is incorrect... but how did the idea emerge? Through observation and experimentation.

Spontaneous generation was consistent with observations: the above recipe did produce mice in experiments. However, this hypothesis ('possible explanation') was rejected when later evidence, in better-designed experiments, contradicted the hypothesis. So, a new hypothesis was proposed to explain the appearance of the mice, which was tested against the evidence... and so on. Briefly, this is the evidence-based, scientific process.

More recently, the dangers of smoking were still being debated into the 1990s:

... a causal role for smoking [has] not been proved beyond reasonable doubt.

--- Eysenck (1991), p. 429

All scientific knowledge emerges in a similar way: observations lead to hypotheses, which are tested against evidence. If the evidence contradicts the hypothesis, the hypothesis is rejected. If the evidence is consistent with the hypothesis, the hypothesis is temporarily accepted (until any contradictory evidence emerges).

Hypotheses not contradicted by large amounts of evidence, over a long time, are sometimes called laws or theories (such as the 'law of conservation of energy'). Theories and laws can be disproven if contradictory evidence emerges. Knowledge in all scientific disciplines is accumulated using a similar evidence-based process.

1.2 Evidence-based research

Every discipline changes, develops, improves, and adapts---usually through research. Your discipline is not the same as it was \(10\) years ago; it will change in the next \(10\) years. Scientists, engineers and health practitioners need to know how to understand and adapt to this change.

To remain current in your discipline, understanding research is vital, even if you will not be conducting research yourself. You still need to know the language, tools, concepts and ideas of research: you need to know how to critique research. Research is the foundation of science.

Scientific research systematically answers questions using data; that is, science seeks evidence-based answers. 'Evidence-based research' refers to research conclusions based on evidence, rather than hunches, feelings, intuition, hopes, or tradition. The evidence comes from analysing the collected data.

Definition 1.1 (Data) Data refers to information (observations or measurements) obtained from a study, such as numbers, labels, recordings, videos, text, etc.

A dataset refers to an organised and structured collection of data.

Research involves designing studies to collect data, and analysing that data; this book covers both.

1.3 Example: research in action

During 1988/1989, an unusually high number of cases of the Legionella longbeachae infection were observed in South Australia. The researchers wanted to identify the source of the infection to prevent further infections.

The researchers noticed that many of those infected were gardeners who had recently handled potting mix, so they hypothesised that the infection was associated with using potting mix. They designed a study to test this hypothesis, then collected data from \(100\) people (\(25\) with the infection, and \(75\) people of similar age and sex without the infection).

The researchers classified and summarised the data, then analysed the data to reach an evidence-based conclusion: potting mix was partially, but not solely, responsible for the infections. The researchers communicated their recommendations to reduce the risks of people contracting the infection.

In this book, we learn about the six steps of research. Arrange these steps into the common order:

Step 1: the question.

Step 2: the study.

Step 3: the data.

Step 4: the data.

Step 5: the data.

Step 6: the results.

1.4 Types of research

Research can be broadly classified as qualitative or quantitative, which are different yet complementary approaches to answering research questions (Table 1.1). Both methods have advantages and disadvantages, and can be used together (called mixed methods research). Deciding to use qualitative, quantitative or mixed methods approaches depends on the purpose of the research.

TABLE 1.1: Briefly comparing qualitative and quantitative research
Qualitative Aspect Quantitative
Feelings, opinions What Measured or observed data
Suggest hypotheses Why Tests hypotheses
Detailed Conclusions General
Words, pictures, ... Data Numbers, measurements, ...
Usually small samples are studied Size Often large samples are studied
Time-consuming Time More efficient
Rarely generalisable Applicability Sometimes generalisable
Interviews, focus groups, diaries Examples Experiments, surveys, measurements

Briefly, qualitative research leads to a deeper understanding, usually from a very narrowly-defined group. Meanings, motivations, opinions or themes often emerge from qualitative research. In contrast, quantitative research summarises and analyses data usually from large groups, using numerical methods, such as averages and percentages. In quantitative research, typically information about a large group of interest (a population) is found from a subset of the population (a sample).

Definition 1.2 (Quantitative research) Quantitative research summarises and analyses data using numerical methods, such as averages and percentages.

This book is about quantitative research.

Example 1.1 (Types of research) Suppose we wish to learn about the perceived benefits and barriers to people buying electric vehicles (EVs).

A qualitative research study might use two small focus groups: one group comprising people who purchased an EV, and another group comprising people who purchased a non-EV. The researchers ask each group about the reasons for their purchase.

A quantitative research study might survey a large number of buyers of EVs and buyers of non-EVs, and ask the buyers' age, sex, and multi-choice questions about the reasons for their purchase. The survey responses could be analysed by numerically summarising, and comparing, the responses for buyers and non-buyers of EVs.

A mixed methods study may combine both of the above.

1.5 The steps in research

The research process ideally follows the process in Fig. 1.1, but this is not always possible or practical. The process is not always linear: researchers may jump from step to step as necessary, and research usually leads to new research questions. Nonetheless, each step is important:

The six basic steps in research

FIGURE 1.1: The six basic steps in research

  • Asking the research question (Chap. 2). Research begins with a question.
  • Designing the study (Chaps. 3 to 9). Evidence-based research uses data to answer questions. A study must be designed to obtain that data, which includes determining who or what to study, how to find them, what information to obtain, and ensuring data are obtained ethically.
  • Collecting the data (Chap. 10). The data collection process must be ethical, reproducible and clearly documented.
  • Classifying and summarising the data (Chaps. 11 to 18). Before analysis, the data must be classified and summarised. (A computer is useful.)
  • Analysing the data (Chaps. 19 to 39). Analysis refers to determining how the data answer the research question, and depends on the type of data and the research question. (A computer is useful.)
  • Reporting the results (Chaps. 40 and 41). Communicating the results appropriately, accurately and ethically is important, including any limitations.

1.6 Using software in research

Statistical software (such as jamovi, R, SAS, SPSS, etc.) is useful for summarising and analysing data. Statistical software:

  • is designed for working with large datasets.
  • encourages reproducible research (Sect. 4.3).
  • allows high-precision formatting and graphics.
  • is powerful; with some programming skills, almost anything is possible.
  • is specifically designed for analysing and working with data.

This book sometimes shows output from jamovi (The jamovi Project 2022), but using jamovi is not essential for understanding this book.

Using spreadsheets in research for storing and analysing data requires care; extremely expensive and dangerous errors have been made due to using spreadsheets (AlTarawneh and Thorne 2017):

  • Spreadsheets may change data (e.g., reformatting entries as dates) when not appropriate (Ziemann, Eren, and El-Osta 2016).
  • Spreadsheets may include formulas with errors that are difficult to locate and hence fix (Panko 2016; London and Slagter 2021).
  • Spreadsheets do not leave a record of how the data were analysed or prepared. Keeping a record of the analysis, preparation of variables, and other operations with the data is good scientific practice (reproducible research; see Sect. 4.3) (Simons and Holmes 2019).
    • Spreadsheets often produce poor graphs (Su 2008).

Problems with spreadsheets, as with any software, are often due to human error, but spreadsheets make errors hard to find and fix. While spreadsheets can be useful for data collection and manipulation, they are not designed for scientific analysis. Be careful using spreadsheets for research and analysis.

1.7 Exercises

Answers to odd-numbered exercises are available in App. E.

Exercise 1.1 Consider the research question: 'Which of three different junctional tourniquets are quickest, on average, to apply?' Is this RQ likely to be answered using a quantitative or qualitative research study? Explain.

Exercise 1.2 Consider the research question: 'Why do people dump rubbish in mangroves?' Is this RQ likely to be answered using a quantitative or qualitative research study? Explain.

Exercise 1.3 Consider the research question: 'What percentage of the population have side-effects from a medication?' Is this RQ likely to be answered using a quantitative or qualitative research study? Explain.

Exercise 1.4 Consider the research question: 'What is the average number of roof-top solar panels on domestic homes?' Is this RQ likely to be answered using a quantitative or qualitative research study? Explain.