Table 2 shows the overall associations between sickness behaviour, asthma-related quality of life, self-rated health and inflammatory cytokines divided into quartiles with quartile 1 being reference. Because a substantial proportion of IL-5 (55% at visit 1 and 58% at visit 5) fell below the limit of detection, quartile one and two were collapsed to one reference category. The associations between the PROMs and the inflammatory cytokines, divided into quartiles are presented in Fig 1. Here, IL5 is linked to asthma.