Table 1.

Characteristics of the four different population groups investigated in this study and the commercial serological assays performed in each population group.

Group	PSL (N = 40)	HC (N = 40)	GP (N = 41)	EM (N = 41)
Group definition	Persistent symptoms attributed to Lyme disease	Controls	Primary care	Acute Lyme (erythema migrans)
Borrelia assays	Serion ELISA ↓ Euroimmun EUROLINE–WB Euroimmun EUROLINE–RN–AT Mikrogen RecomLine * Mikrogen RecomBead * Serion Multianalyte system $	Serion ELISA ↓ Euroimmun EUROLINE–WB Euroimmun EUROLINE–RN–AT Mikrogen RecomLine Mikrogen RecomBead Serion Multianalyte system	Serion ELISA ↓ Euroimmun EUROLINE–WB	Euroimmun ELISA/BioMérieuxVidas Lyme ELFA ↓ Euroimmun EUROLINE–RN–AT
					p-value
Female gender	20 (49%)	26 (65%)	23 (56%)	25 (61%)	0.62 #
Average age (years)	48	48	61	48	<0.001 **
Country	Netherlands	Netherlands	Netherlands	Romania

Data are presented as numbers and percentages. Statistical analysis used: # = Pearson’s Chi square test, and ** = Kruskal–Wallis test. PSL—patient group with persistent symptoms attributed to LB; HC—healthy controls; GP—patients in primary care with Borrelia seropositivity; EM—patients with a recent clinical diagnosis of EM. * Mikrogen RecomLine and Recombead (Mikrogen GmbH, Neuried, Germany); $ Serion Multianalyte (Virion/Serion GmbH, Würzburg, Germany). Arrow ↓ indicates that an ELISA assay was performed first before the other assays depicted under.