Figure 1. Total direct cost as a fraction of household income (per month) in cases and controls.

Whiskers contain 100% of the data, not including extreme values (those data observations which lie more than 1.5*IQR lower than the first quartile or 1.5*IQR higher than the third quartile). The reference line at cost/income = 0.4 indicates the threshold for catastrophic health expenditure.