Does type and number of used substances affect the severity of illness in patients with substance use disorders?

Table 5 Correlations between Addiction Intensity Scale (AIS) scoring and some clinical and addictive characteristics

	Addiction intensity score
	R	P value
Age of patients	−0.073	0.462
Age of onset	−0.319	0.001*
Duration of addiction	0.241	0.014*
Education	0.270	0.006*
Total number of substances	0.492	< 0.001*
Current number of substances	0.203	0.039*