I get what you’re saying, and to be frank I appreciate the skepticism, and the drive to reality-check the numbers. Sometimes the numbers are over- or under-stated, or not reasonable effects.

In this case the abstract actually says it’s a significant change:

> “was significantly reduced in the HC group (1.04±0.31 vs 0.87±0.24 , p < 0.001)”

They include the P-value. You’re right it’s hard to know what the +/- means, typically that’s standard deviation, and not reflective of confidence intervals. Literally the confidence interval at 95% by definition would be smaller than the difference, that is if it used the same model used by the test.

It’s a whole thing about reporting and displaying confidence intervals, versus standard deviations, etc. Sometimes it’s straightforward to report standard deviation, but is not reflective of whatever statistical model was actually used. Frustrating, but not usually an author issue, also a journal guidance issue.

Oh, and the reason standard deviation does not indicate whether effect size is significant is in part that it doesn’t account for the number of individuals, nor the actual statistical model. Standard deviation is a simple university summary.