Scientific writing-Part 5: Results

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Scientific writing-Part 5: Results

1 A brief description

“Results” is the heart of the paper. This is usually the most straightforward and easiest section to write. It contains exactly what the name says, results. In this section you present your findings. Present the data, digested and condensed, with important trends extracted and described. Because the results comprise the new knowledge that you are contributing to the world, it is important that your findings be clearly and simply stated. Unclear or messy ones will only confuse the poor reader, so be as simple, clear, concise and neat as possible. Most of your outline should be concerned with this section. Statistical significance, direct biological interpretation can be present here. Indirect interpretations can be discussed in the "Discussion" section. Illustrations are important. Put the data, figures and tables in the most logical order and not in chronological order, although that might be tempting to do on a first draft. Many authors organize and write the results section before the rest of the report.

Results are written in present or past tense. The present tense is more appropriate when describing results that you think represent absolute values. (The size of human red blood cells is about 7 um, and you would expect any other researcher to find the same number.) The past tense is more appropriate when describing unique aspects of your results, such as a percent increase in reaction rate at an elevated temperature. It is possible; after all, that if someone repeats your work they may not find quite that exact percent increase, though of course you do expect them to find enough of an increase to agree with you that temperature has a stimulatory effect.

The Results section consists of at least three components: 1) one or more paragraphs that describe the results, 2) figures (graphs, diagrams, pictures), and 3) tables.

2.1 Results description

This section should summarize the findings. Point the reader to patterns or trends observed in the data (but don’t interpret such patterns or trends). When recording the results, move from the most general to the most specific. Further, be sure to fully describe the results in the text. Tables and graphs may be included to support the text, but they should not substitute for the written description. Be sure to support any generalizations made with facts, but do not interpret or draw conclusions from the data.

Explain your actual findings, using subheadings to divide the section into logical parts, with the text addressing the study aims. Link your writing to figures and tables as you present the results. For each, describe and interpret what you see (you do the thinking -- do not leave this to the reader). If you have many similar figures, select representative examples for brevity and put the rest in an appendix. Mention any uncertainty in measurement or calculation, and use an appropriate number of significant decimal digits to reflect it. Make comments on the results as they are presented, but save broader generalizations and conclusions for later. Answer the question "what did I find out?"

In writing about the data, the author should guide the reader through the tables and figure. For example, draw the reader's attention to statistically significant findings, trends in the data, and comparisons among data sets. Do not discuss what the data mean in the results section. The description of data should flow from presenting general features to more specific points.

The results should be short and sweet, without verbiage. Do not say "It is clearly evident from Fig. 1 that bird species richness increased with habitat complexity". Say instead "Bird species richness increased with habitat complexity (Fig. 1)". However, do not be too concise. The readers cannot be expected to extract important trends from the data unaided. Few will bother. Combine the use of text, tables and figures to condense data and highlight trends. In doing so be sure to refer to the guidelines for preparing tables and figures below. Results should contain an objective and clear description of the experimental finds presented in a logical sequence that aids in the readers understanding. This sequence is not necessarily the chronological order in which the experiments were performed.

Here you state and show what you saw or measured. Do not make conclusions or discuss the data. That comes in the next section. Do not report what you expected to happen in the experiment. They are analyzed so that they are meaningful. For example, if you monitored growth rates by taking four cell samples every hour, then counting and averaging the numbers, the number of cells you found in the original samples is not presented. Most important here are the final values, expressed as the average number of cells/ml, plus or minus a measure of variation like the standard deviation. You must also state what measure of variability you used, and the statistical analysis of its significance (usually with a reference).

Example: Synergistic antiviral therapy by drugs A and B. Mice (10 per group) were infected on the dorsum with herpes simplex virus type 1 (HSV-1) and were treated on days 1-5 with the indicated drugs. Drugs A and B were dosed orally at 2 and 4 mg/kg, respectively. Standard deviations were less than 20% of the means. Lesions were scored on a 0-5 scale as described in Methods.

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An example of a well-constructed table is listed below.

The title is simple and clear.

The column headings are accurate and contain units when necessary.

The uncluttered data is easy to read and understand without reference to the text.

The data is sorted in a logical order. The most important data should be first if appropriate.

The number of significant digits in the values do not exceed the precision of the determination.

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2.2 Figures and Tables

There are a multitude of ways to format tables and figure. The key points to remember is that each table or figure must have both a number and a title that explains what data are presented. Any symbols used in the tables or figures should be explained with legends. Every table or figure used must be referred to in the text of the results section. However, it is not acceptable to simply say, "Results of the study are presented in Table 1," and use that for the complete results section. The results section should describe the data. A final point about tables and figures is that they should be able to be looked at without any text and be understandable.

In this section summarized data are presented in table or figure formats. Raw data is not presented (e.g. all of the measurements of moose antler length collected), but rather analyzed data are presented (e.g. mean moose antler length). Sometimes it is better to divide a table in two and make two clear tables rather than have one complicated table. Depending upon journal style, a complex figure might have descriptions, arrows or numbers. If these features can be placed on the figure or in the footnotes to the table, the reader will not have to refer to the figure legend or search through the text to find any needed information. Be conservative on the number of tables and figures used because they are expensive for journals to reproduce and take up additional space. In addition, some journals may reject an article with too many figures or tables. Your best guide is to familiarize yourself with the journal, and know what it most commonly published.

What about photographs? Obviously these are a kind of raw data, but they must be either typical or representative (or occasionally exceptional; say which!), depending on the point you are trying to make. Generally, your data should be given as tables and figures (graphs and photos), each with a number and a title. Data that can be described in a sentence or two can be written out. Give each piece of data only once, not, for example, in a table and a graph, nor in a figure and the text. The text in the Results section should act as a tour guide, leading your reader from item to item (every figure or graph must be referred to, and in order), and drawing attention to the highlights, especially to those that will be important in making conclusions. What, if anything, all this means is given in the discussion.

Remember to number figures and tables consecutively throughout the paper. Refer to figures and tables within the paragraph as you describe your results, using the word Figure or Table, followed by its number, for example, "(Figure 1)." If possible, place each figure or table at the end of the paragraph in which it is cited.

Include your Chi-square statistical analysis in the Results section. Report your data as accurately as possible as it happens.

The results section should summarize the data from the experiments without discussing their implications. The data should be organized into tables, figures, graphs, photographs, and so on. But data included in a table should not be duplicated in a figure or graph.

All figures and tables should have descriptive titles and should include a legend explaining any symbols, abbreviations, or special methods used. Figures and tables should be numbered separately and should be referred to in the text by number, for example:

* Figure 1 shows that the activity decreased after five minutes.

* The activity decreased after five minutes (Fig. 1).

Figures and tables should be self-explanatory; that is, the reader should be able to understand them without referring to the text. All columns and rows in tables and axes in figures should be labeled. See appendix B for graphing instructions.

Figures

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The sample figure shown on the next page exemplifies an easily understood figure.

The purpose of the figure is readily discernible by visual inspection.

The title of the figure is clear, simple, and relevant.

The legend contains adequate information to understand the figure.

The uncrowned figure contains adequate and balanced white-space.

The curves are labeled within the figure (if acceptable by the journal) to avoid the need to flip visually between the graphic and the legend.

The curves don’t extend beyond the data points.

The symbols clearly distinguish the curves.

The axes are labeled clearly and have meaningful values with appropriate intervals.

The text remained legible after photographic reduction.

2.3 Notice

If you have any questions about the clarity or logic of your work, seek out colleagues. Their advice can only improve your paper. Remember basic writing techniques and begin every paragraph or section with an introductory sentence. Present each table or piece of data in a neat package. Avoid excessive abbreviations. Describe the results as concisely as possible and end with a sentence reflecting your conclusions. But do not relate these conclusions to the overall field or discuss the significance just yet.

Add a bit of explanation and this section is finished. An occasional conclusion (especially if they are not incredibly significant or may detract from the main conclusions of the paper) may be appropriate here, but save most of the important interpretations and conclusions for the discussion section.

Results

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· Concentrate on general trends and differences and not on trivial details.

· Summarize the data from the experiments without discussing their implications

· Organize data into tables, figures, graphs, photographs, etc. Data in a table should not be duplicated in a graph or figure

· Title all figures and tables; include a legend explaining symbols, abbreviations, or special methods

· Number figures and tables separately and refer to them in the text by their number, i.e.

1. Figure 1 shows that the activity....

2. The activity decreases after five minutes (fig. 1)

RESULTS

1. This is where you present the results you've gotten. Use graphs and tables if appropriate, but also summarize your main findings in the text. Do NOT discuss the results or speculate as to why something happened; that goes in the Discussion.

2. You don't necessarily have to include all the data you've gotten during the semester. This isn't a diary.

3. Use appropriate methods of showing data. Don't try to manipulate the data to make it look like you did more than you actually did. "The drug cured 1/3 of the infected mice, another 1/3 were not affected, and the third mouse got away."

Key Points

What did you observe?

For each experiment or procedure--

Briefly describe experiment without detail of Methods section (a sentence or two).
Report main result(s), supported by selected data--Representative: most common, Best Case: best example of ideal or exception