Figure 2
From: Derivation of normative data for the COPD assessment test (CAT)
Normative values, and distribution (by percentiles) for the overall CAT score by age group and sex. CAT: COPD assessment test (scores range from 0 – 40). Boxes represent the inter-quartile range with the white line within the box representing the median. Whiskers represent extreme values within 1.5 IQR of the lower and upper quartiles, respectively. Values beyond this (outliers) are represented by discrete points in the graph.