PDF reading order is easy to miss when the page looks well organized. A reader can follow two columns visually, while software may encounter parts of the content in a different sequence. The document's appearance and its underlying structure answer different questions.
Consider a sample newsletter with a left column explaining registration and a right column listing event dates. If copied text switches between the columns every few lines, a reader reusing the information has to reconstruct the article manually. A clean-looking page has still created extra work.
Review a sequence, not a screenshot
Choose a page where the order matters. Read its first paragraph, then copy or extract the text and find that paragraph in the result. Does the next sentence follow it? Has a caption or sidebar been inserted into the middle?
PDF to Text offers a way to inspect extractable text. Use its output as a diagnostic clue. It can reveal awkward sequences or missing text, but it does not verify every accessibility requirement or establish exactly what every screen reader will announce.
W3C's PDF reading-order technique explains the role of structure in tagged PDFs and includes testing with assistive technology. That is a broader check than seeing whether text can be selected.
Fix the source when you can
If you control the source document, review how it was built. Ordinary paragraphs and actual column features can be easier to maintain than a page assembled from many independently positioned text boxes. Exporting the same visually complex source again may reproduce the same structural problem.
For a short handout, consider whether a single column would communicate the information more clearly. This is a content decision as well as a formatting decision. A complex layout should earn its space by helping the reader understand the material.
Keep meaningful headings, captions and reading sequence in mind while preparing the source. Then inspect the exported PDF rather than assuming the source application's appearance transferred every useful structural detail.
Make the review match the audience
A document intended for broad distribution deserves more than a quick visual glance. Test with the required accessibility tools and, where practical, the assistive technology your audience uses. If a formal accessibility requirement applies, follow that requirement's full checking process.
Compare Plain text and Keep approximate positions in PDF to Text when diagnosing a difficult page. The position mode is a best-effort layout aid; it does not repair tags or establish the sequence an assistive technology will use. Pair extraction checks with the source-document and accessibility review rather than treating readable plain text as a conformance result.
For the newsletter example, a useful acceptance check is simple to state: the main article should read from its beginning to its end without a sidebar interrupting a sentence. Write that requirement down before designing the page. It gives both the author and the reviewer something concrete to verify.