The authors of our Writing Guides are Marina Hurley and Liza O’Donnell. Within these documents, we also provide links to additional writing resources. If you are interested in seeing a topic covered, please email firstname.lastname@example.org for further information.
In a nutshell: Any additional information or data that supports or extends the main document or report.
Appendices (singular; appendix), supporting information, and supplementary data are terms that describe information presented as an attachment to a report, paper, article or thesis. The term used depends on the type of communication being prepared; appendices are usually used in theses and reports, whereas supplementary data or supporting information are often terms used by scientific journals.
Scientific journals place constraints on the length of published papers and actively encourage the use of supporting information to keep papers short and concise. Supporting materials are also peer-reviewed and their inclusion should be scientifically relevant.
In general, supporting information is:
– Relevant to the main report and provides extra information that will expand the reader’s knowledge of the topic.
– Not strictly necessary or essential; the report should include all of the information required to address the research problem and still be understandable to the reader without referring to the supporting information.
– Too cumbersome for the main report.
Examples of supporting information include:
– Extra information about methods used in the research project; for example, details on reagents, specific conditions used, and detailed descriptions of measuring instruments.
– Large and complex datasets, with a summary or subset of the data included in the main report. Large spreadsheets using software such as Excel can often be inserted in supporting information.
– Detailed drawings, maps, diagrams or charts.
– Sample calculations or detailed mathematical derivations.
– Questionnaires or surveys.
– Raw data or analytical data (e.g. data produced from instruments), with a summary of the processed data included in the main report.
– Detailed text, such as transcripts of interviews and excerpts from surveys.
– Summaries of other reports that expand the reader’s knowledge of the topic.
For studies with large datasets, the use of a public data repository could be appropriate. Check the journal you are submitting to as they usually provide information on the types of data repositories that should be considered. Lists of data repositories are also available (see Further Reading).
Divide the information into appropriate sections, with each section on a separate page. Each section should have a title that clearly explains its content.
Label the sections; appendices are usually labelled Appendix 1, 2, 3 (or A, B, C) whereas as supporting information is often labelled according to its type; for example, Supplementary Table 1, Supporting Figure 1, Supplementary Movie 1. As with figures and tables in the main report, supporting information is numbered according to the order it is mentioned in the text of the report.
The page numbering should be continued from the last page of text in the main report.
Always remember to check publisher’s requirements and editorial guidelines. Figures and tables should be carefully formatted as per editorial requirements, ensuring appropriate file formats are used. Also look at different formats presented in documents specific to your field.
Insert and cite
Insert appendices at the end of the report, after the bibliography. Ensure all supporting information is appropriately cited in the report; it should be easy to find. Also ensure it is listed in the table of contents (if used).
Critically evaluate your supporting information; Is it relevant and does it expand the reader’s understanding?
© Liza O’Donnell & Marina Hurley 2016
Example Instructions to Authors
What is a figure?
Figures visually present information that cannot be clearly explained as written text or presented in a table. Figures can include graphs, flow charts, photographs, maps, illustrations, micrographs and diagrams. They can be simple; for example, a one-line graph that conveys a simple relationship between an x and y variable (see Figure 1), or they can contain multiple components, such as a graph, a diagram, a micrograph or photograph (see Figure 2). Figures have labelled components and a figure legend that clearly describes these components and summarises the key features.
A line graph conveying a simple relationship between two variables. In this case, the variation of a measured hormone over time.
Figure 2. An assembled figure contains multiple panels
Planning your figure
As with tables, figures help the reader understand what you have found: for example, key observations, statistically significant results, expected or unexpected trends in the data or any matter that needs further explanation. Figure design occurs after the data has been analysed and the main findings are apparent. The figures are usually presented in a results section and discussed in relation to your research question or problem statement that was raised in your introduction. What figures you present also depends upon whether you are writing a report, journal article or thesis. A report can have a multitude of figures, while journal articles usually have strict page limits that force firm decisions on the number that can be included. Usually, there is more leeway for additional figures in a thesis.
When deciding how to place figures, prepare a mock layout to work out where each component will go, either by drawing boxes on paper or by printing draft versions of what you expect the final version to look like. Will the figure take up one column or will it be a large multi-panelled figure that takes up two columns of a journal or one entire page of a thesis?
Figure 3. Consider whether your figures are small enough to fit in one column to save space; larger figures may require two columns.
Preparing figures for journal publication
If you are preparing figures for journal publication, it is essential to first check the publisher’s requirements. Most journals have strict and detailed instructions with specific criteria: for example, image size, file type, resolution, colour space (e.g. RGB) and font types. If these criteria are not followed exactly, your publication may be returned by the editor for further changes.
Turning your raw data into a published figure: stay true to your data
Scientists are ethically bound to present their data truthfully and transparently. As a scientist, it is your responsibility to ensure that your figures accurately convey your original data and observations. In addition, universities and research centres must comply with the Australian Code for the Responsible Conduct of Research. As you manipulate your raw data into graphs and prepare your images for publication, your raw data is inevitably transformed in some way; even simple line graphs are a transformation of a set of experimental values. Photo-editing programs can also transform digital images by re-sampling (see fact sheet: Preparation of figures as digital images), which could result in an image that is different to the original.
When preparing figures for publication in any form, it is important that you adhere to your organisation’s requirements for transparency and peer review. How you manipulated your raw data into the published figure must be transparent and repeatable. For example, does your final, published image look like the fluorescently-labelled image you saw down the microscope? Is the photo one actually taken of your study subject and not another one similar to yours? Does your graph accurately explain the data, or have you left out some aspects of the data and inadvertently misrepresented your original findings? Make sure you save your files at each step of the transformation from raw data into a final published figure, and keep the files together in one folder.
What software do I use?
First, establish what software is freely available to you via your university or organisation. Graphs and charts can be drawn in Excel and in a variety of statistical programs. CorelDraw or Adobe Photoshop and Illustrator are often recommended by publishers to draw diagrams, and to compile your images, graphs and diagrams into a publication-quality figure.
Some software is expensive while free software is readily available on the internet with workflows available to show how to create publication-quality figures using free software. For any type of software, open-source software is often a good choice as it is completely free and is supported by an online community that engages in ongoing support and development. For example, freemind software for mind-mapping and Gimp for photo and image manipulation, and see Wikipedia for software listing for graphic software.
Microsoft Powerpoint is often readily accessible and can be useful for drawing or compiling diagrams. Set the page layout to A4 portrait and add all components, using alignment tools and rulers to align panels and text. However, Powerpoint only exports lower resolution files for monitors, rather than higher resolution required for printing. A way around this is to print the Powerpoint file to a pdf (using Adobe Acrobat Professional) and select High-Quality Print (300 dpi) in “Preferences”. The resulting pdf file can then be cropped and saved as a TIF file with a 300dpi resolution (use either Adobe Acrobat or Photoshop to crop and save as a TIF).
The essentials of a good figure
Once you have created the figure, check the following criteria:
– Does it look good when printed on paper? Can all the features of each different components be clearly seen?
– Are the labels clear and specific?
– Is the resolution of the final assembled figure appropriate?
– Does the legend title convey the key finding?
– Do the details in the legend adequately explain all of the components?
– Is the figure referred to at the appropriate places in the results section? Does the figure accurately convey what is written in the results?
– Ask a colleague to proofread and check the clarity of your figure. Can they understand the overall message? Do they understand what the different components are?
© Liza O’Donnell & Marina Hurley 2016
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Written by Liza O’Donnell & Marina Hurley 2015.
How to ensure your photos, graphs and illustrations are of suitable quality for publication. Digital images are stored in different formats, depending upon the software. Common examples include TIFF, JPEG and EPS. Before preparing figures, it is vital to check the resolution requirements to ensure that the appropriate resolution is used, for the web and for print.
Resolution describes the number of pixels within an image and image quality increases with resolution. A pixel is the smallest unit of digital information that forms an image. Resolution can be expressed as the number of pixels per dimension (e.g. 1200 pixels wide by 750 pixels high) or as the number of pixels within a specified area (pixels per inch or ppi). An image that has a resolution of 300ppi and is 4 x 2.5 inches in size, will be 1200 pixels wide (4 x 300) = and 750 pixels high (2.5 x 300). In general, the more pixels you have per unit area, the more detailed the image will be and the larger the file size. Some software (such as Photoshop) allows you to change the units to pixels per centimetre; however, the publishing standard is usually ppi.
The resolution of an image for viewing on a monitor is described in ppi, whereas the term dots per inch (dpi) describes the resolution of a printed image, as printers print dots and not pixels. The terms are used interchangeably but for most purposes, ppi and dpi are essentially the same thing to describe resolution. To view an image on the accepted resolution is 72ppi as most LCD monitors display 67-130ppi. When submitting figures for publication, 300 ppi is the generally accepted resolution for print images.
If your image needs to be 300ppi, then you need to consider the size of your image in the final printed form and the number of pixels in your total image. A photo that will be 4 x 2.5 inches when printed will need at least 1200 x 750 pixels to achieve the desired print-quality resolution of 300 ppi. If you have fewer pixels, then the quality of the image (i.e. the resolution) will be reduced. You can also quickly check whether the resolution is sufficient by zooming your image to 400% and if it is blurry (pixelated), then the image may not reproduce well when printed.
When re-sizing an image, some software programmes automatically change the size of the image without changing the number of pixels. For example, if you re-size a 1200 x 750 pixel image from 4 x 2.5 inches to a 12 x 7.5 inches the number of pixels will remain the same but the resolution will drop from 300ppi to 100ppi . The larger image will look OK on the screen, but the image quality will be poor if it is printed. Whatever image size you require, ensure the final version is at the desired resolution.
Colour space is the way colour information is stored in a file. Grayscale refers to black and white (and grey!) images which use a single colour channel. RGB is a commonly-used colour space that divides colours into 3 channels: Red, Green and Blue. RGB is used by computers and digital devices and is commonly used by publishers who want to make sure their documents are properly displayed on their reader’s devices. CMYK is a four channel colour space (cyan, magenta, yellow and black) commonly used during the printing process. An RGB image might need to be converted to CMYK if it will be printed. Some publishers will do the conversion themselves, so you need to be aware that the colour of RGB images may look different when converted to CMYK.
Re-sampling changes the number of pixels in an image. Re-sampling is different to re-sizing. Down-sampling removes pixels and creates a smaller image, whereas up-sampling adds pixels using algorithms. Because re-sampling adds or removes pixels, a loss of image quality could result. This could be particularly important if you are presenting images that are taken from a microscope; it is imperative that re-sampling does not change the specific features of the data within the micrograph. As a general rule, create your images at the highest resolution possible to avoid the need to re-sample. However, re-sampling may sometimes be necessary; for example, when converting a very high-resolution image to a small size (2 x 2 inches). Always keep original files and ensure that the re-sampling process only happens towards the end of the figure creation process, so that you can go back to the original image if needed.
Image compression: Some file types (e.g. JPG) compress the pixels in the image to reduce file size. Be aware that different compression methods can affect image quality. Pay attention to the publisher’s requirements for compression and whether your software compresses by default.
Raster vs vector images: Raster images use raster data that is stored as pixels, for example, digital photographs. Because raster images use pixels, the quality is highly dependent on resolution. Vector images use vector data comprised of lines and curves, for example, line graphs. Because vector images do not use pixels, they can be re-sized to a very large size without becoming pixelated and losing quality. If you are publishing images that are line graphs only, consider using vector format files such as EPS. However, if you are assembling a line graph into a larger figure that includes digital images, the entire figure will become rasterised at some point; meaning that your vector image will become a raster image and need high resolution.
© Liza O’Donnell & Marina Hurley 2015
* Digital photography fundamentals: Understanding resolution and bit depth..
* Image resolution and print quality.
* How to create publication-quality figures.
* The difference between image re-sizing and re-sampling.
* Science: preparing your art and figures.
Any suggestions or comments please email firstname.lastname@example.org.
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What is a table?
Tables present the results of data or information collected from a study. The purpose of a table is to present data summaries to help the reader to understand what was found. Not all data needs to go into a table: some results are simply presented as written text in the results section; data that shows a trend or a pattern in between variables is presented in figures, while additional data not necessary to explain the study should go into the appendix.
Tables should convey data or information clearly and concisely and allow the key message to be interpreted at a glance. Tables often include detailed data in rows and columns, while sub-columns are often nested within larger columns.
Designing your table
Once you have decided what data to present, jot down a rough draft of the table headings on paper to determine how many columns and rows you need. Choose categories with accurate labels that match your methodology and analysis. Before you spend too much time designing the layout of your table, check that you are following the format expected within your discipline or organisation as table formatting requirements often vary considerably; if you are preparing a science report, refer to the relevant In-House Style Guide(s) or if you are preparing a journal article, meticulously follow the journal’s Instruction to Authors.
Title or Legend
Consider the objective and key message of each table. The table title is typically placed at the top of the table. It should stand alone: it needs to be clearly understood by your target audience without them needing to go back to the results or methods sections. The title should be concise and describe what was measured, e.g. ‘Reproductive hormone levels during contraceptive administration in men’. Frame the title so that it conveys the key results, e.g. ‘Reproductive hormones are suppressed during contraceptive administration in men’.
Take care to ensure the sub-headings are meaningful and accurate. The row and column headings clearly explain the treatment or data type, and include units. In the sample table below, the experimental details are given in the row headings (time points during the administration of a contraceptive), and the data measured (hormones) are given in the column headings.
Explanatory notes and footnotes are placed at the end of the table. Make sure that all abbreviations are defined and that the values are explained. For example, if the values are a percentage, mean ± SEM, n per group.
Drawing and formatting the table
Tables for publication are usually created in Word, using the Insert Table function. For instructions see: Office Support: Insert or create a table. Tables can also be created from existing datasets in Excel, and then cut and pasted into Word, or exported into Word as an image.
– Use a separate cell for each piece of information; avoid having to insert tabs or spaces which may cause the text to be unintentionally moved when the formatting is adjusted. Add your headings and data to each cell.
– The table then needs to be formatted to improve readability and clarity. Select the entire table or individual rows or columns and right click. Options will appear where you can modify the table size, cell height and width, and format the borders.
– Word tables will have borders on each side of the cell by default. Formatting the borders by selecting columns, rows or individual cells will help the table to take shape and improve visual clarity. In the sample table above, horizontal borders have been used sparingly to improve clarity.
Formatting borders helps a table to take shape and improve clarity. Select and de-select the horizontal and vertical lines you want to use as borders
– Cells can be merged to create headings above sub-headings (see example below). Select the cells you want to merge then select the Merge Cells option.– Text within the table can be formatted by selecting the text, then formatting it as normal.
– Make sure that the columns and rows are well separated and that the table is not cluttered and is easy to read. Imagine the reader looking at your table: do they have access to all of the information they need and can they easily understand the results?
Citing the table
Always cite the table at the relevant point in your text. Avoid repeating the details that are presented in the table, and use the text to direct the reader to the main message, e.g. ‘Contraceptive administration at 14 and 20 weeks significantly suppressed FSH, LH and testosterone levels in men (Table 1)’. Tables should be numbered consecutively throughout the document.
© Liza O’Donnell & Marina Hurley 2015.
Further reading: (external links)
* Creating tables in scientific papers: basic formatting and titles
* How to create and customize tables in Microsoft Word
* Tips on effective use of tables and figures in research papers
* Almost Everything You Wanted to Know About Making Tables and Figures
* Office Support: Insert or create a table
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