Table 3.

Spearman correlations between disease- and group-describing parameters.

Interpretation, variables		ρ	P value
Significant strong positive correlation
	Recent group activity and number of new members	0.769	<.001
Significant moderate positive correlation
	Prevalence and number of groups per disease	0.530	<.001
	Group member count and recent group activity	0.691	<.001
	Group member count and new group members	0.628	<.001
Significant weak positive correlation
	Prevalence and group member count	0.101	<.001
	Time that a group exists and member count	0.111	<.001
No significant correlation
	Time that a group exists and recent group activity	0.011	.39
	Time that a group exists and number of new members	–0.002	.85
	Disease’s minimal age of onset and number of groups per disease	–0.021	.55
	Disease’s minimal age of onset and group member count	0.006	.62