  The Apnea-Hypopnea Index (AHI) is one of the most-used parameters from the
sleep study that allows assessing both the severity of obstructive sleep apnea
and the reliability of new devices and methods. However, in many cases, it is
compared with a reference only via a correlation coefficient, or this value is
at least the most emphasized. In this paper, we discuss the limitations of such
an approach and list several alternative quantitative and qualitative
techniques, along with their interpretations. We propose the assessment of
clinical significance along with the statistical one. Qualitative analysis can
be used for this purpose, or we suggest using the ranking function which
enables consideration of various AHI values with different weights. It can be
reliable for both adult-related and pediatric sleep studies. The dedicated
Shiny web application, written in R, was developed to enable quick analysis for
both physicians and statisticians.
