Figure 2.

K-means clustering algorithm with five distinct clusters. CPM was coded negatively in case there was a malfunctioning of the descending nociceptive inhibitory pathways and positive in case of functioning of these pathways. For temporal summation, higher scores indicate more nociceptive facilitation. Abbreviations. CPM: conditioned pain modulation, CSI: central sensitization inventory, LCADL: London chest activity of daily living, PFCS: post-COVID-19 functional status scale, phys: physician, PPT: pressure pain threshold, pt: patient, Quad: quadriceps, Trap: trapezius, and TS: temporal summation.