Lab Report Writing

Introduction of Your Lab Report

The introduction of your lab report is a chance for you to "hook" the reader and preview the important details you'll be talking about in the later sections of the paper. It's kind of like the first paragraph in a short story or the first act of a play.

While the abstract was a very short summary of the entire paper, the introduction will be a longer section with more detail. It could be anywhere from three or four paragraphs to a couple pages long, depending on the complexity of the topic and, of course, the requirements of your instructor.

Here are some tips for organizing your introduction:

  1. Start off with a very broad introduction to the topic. For instance, let's say you are writing a lab report about an experiment where you tested the effect of temperature on the enzyme catalase. You should start the introduction by talking about what enzymes are and how they work.
  2. Next, narrow down the introduction to talk more specifically about the topic you are investigating, and why the study you did was so important. In the catalase example, you should now talk specifically about what the catalase enzyme does, where it is found, how it works, and why it is important enzyme to study how temperature affects this enzyme.
  3. The introduction should also include a literature review that discusses what is already known about the topic. This where you will summarize the research you have done about your topic. Make sure you properly cite all of the sources you used in your research.
  4. Finally, state the purpose of the study, the hypothesis you tested in your study, and/or the question(s) you were trying to answer.

The introduction should not include details about the procedures you used in your study. Save these for the Materials and Methods section. You should also leave out the results, which will go in the Results section.

Example

Introduction

Osteoporotic fractures, particularly hip fractures, constitute a large and growing problem worldwide, in both women and men, with a profound impact on quality of life [1] and mortality [2]. The fracture risk is influenced both by the genetic constitution and by environmental factors, with lifestyle becoming more important with increasing age [3].

Physical activity, one conceivable and modifiable risk factor, can prevent fractures by improving muscle mass and balance, and by increasing skeletal strength, and thus reducing the risk of injurious falls [4,5]. However, the clinical relevance regarding exercise for maintaining or improving bone mineral density in adult men cannot be determined from existing studies [6,7].

The investigation of the effects of physical activity on the most important outcome—fracture risk—should ideally be evaluated in a randomized study, but this design is unlikely to ever be well performed owing to methodological issues, e.g., study size, compliance, drop-outs, blinding and long-term follow-up. Therefore, it is not surprising that there are no randomized trials in this area.

Although moderate levels of leisure physical activity, such as walking, are associated with a substantially lower risk of hip fracture in postmenopausal women [8], data from prospective observational fracture studies in men are inconsistent. Whereas some studies in men report significant reductions in risk with a high physical activity [9–12], others do not [13–17]. Lack of validation and the absence of regular assessment of physical activity during follow-up may be factors that explain these contradictory results. The analyses in the positive reports have involved few osteoporotic fractures, and no consistent dose-response pattern has been detected. In addition, only a few studies have taken possible confounding by poor health into account, and in none of the studies has it been considered that changes in physical activity and other lifestyle habits might have occurred during follow-up. Thus, it is uncertain whether, to what extent, and at what level physical activity influences the risk of osteoporotic fractures in men. This study therefore investigated the impact of physical activity on the risk of fracture in a population-based cohort of men followed over a 35-y period.

EXPLANATION OF EXAMPLE
In the first paragraph of this introduction we learned some general information about bone fractures. The second paragraph narrowed the discussion down to talk specifically about how exercise is related to bone fractures. The third paragraph tells us why the current study is so important. The final paragraph starts off with a literature review telling us what sorts of previous studies have been performed on this topic. The last sentence then gives us the purpose of the current study.  The numbers in brackets are citations for papers that would be listed at the end of the paper, in the References or Works Cited section. Hover your cursor over highlighted terms for the definition.

Test Yourself (Introduction)

What information should be included in the Introduction of a lab report?  Which of these answers are correct?

a. The purpose of the study
b. General information about the topic being investigated
c. Specific details about how the study was done
d. The conclusions you have made based on the results of your study
e. A literature review that summarizes what is already known about the topic.

Click on the question, to see the answer.