Finding a Research Paper's Supplemental Data

A paper’s main figures may leave you asking where the individual values, additional comparisons, or explanatory files are located. Supplemental material and underlying data can occupy different places. Start with one specific question about the paper, then follow its own labels and links. This guide concerns reading non-clinical research records.

Follow the attachment label from the article

Use the publisher’s article page to look for supporting information, supplementary material, or additional files. Search the article text for the attachment label cited beside the result you want to inspect. A label identifies a particular item; a generic download button may provide only the main paper.

PLOS One’s supporting information guidance explains that published attachments are linked through their captions. Files can include tables, figures, appendices, or datasets. PLOS publishes them as supplied without copyediting. That describes this publisher’s arrangement; another journal may place its attachments differently.

Read the data availability statement separately

An extra figure is not necessarily the collection of values behind that figure. Read the data availability statement for a repository name, dataset identifier, or stated access restriction. Record the exact location rather than assuming every relevant file appears in the article’s attachment panel.

PLOS’s data availability policy distinguishes repository deposits from supporting files and defines its minimum dataset around the reported findings. It does not require every observation collected during an investigation. The policy also recognizes specified access restrictions. These distinctions help frame a search without promising that any particular dataset is accessible.

Hypothetical example: a graph and three attachments

Imagine a fictional paper comparing two instrument readouts. Its Figure 2 refers to S1 Table, while its attachments also include S2 Figure and S3 Text. All names and circumstances in this example are hypothetical. Your question is whether the individual values behind Figure 2 can be located.

S1 Table contains group averages only. S2 Figure repeats the plotted comparison with different axis labels. S3 Text describes the records included in the comparison. None of those descriptions establishes that you have found the individual values. Now inspect the data availability statement: it names a repository deposit containing a separate observations file.

Before connecting that file to Figure 2, check whether its description identifies the same comparison and whether its column labels explain the values. If the repository opens but the file requires permission, record that limitation. Your finding is a located deposit with restricted file access, rather than a completed inspection of the underlying observations.

Ask questions that narrow the remaining gap

• Which attachment or dataset identifier is linked to the particular figure?
• Does the file contain individual observations, calculated summaries, or explanatory text?
• Where are column names, units, missing-value symbols, and exclusions explained?
• Does the accessible description identify the same paper and comparison?
• Is the obstacle a broken link, a missing file, or an explicit access requirement?

Keep those questions tied to the original task. A request for the values behind one graph is more precise than a request for all supplemental material. If a file opens but its meaning remains unclear, identify the unexplained column or label instead of treating successful download as successful interpretation.

Finish with a compact finding: the requested item, the location inspected, what could be read, and what remains unavailable. That record lets another reader continue at the unresolved point without mistaking a caption, a repository landing page, or a summary table for the complete underlying data.

Sources

• PLOS One: Supporting Information
• PLOS One: Data Availability