Table 3.

Main causes of chronic cough within each Italian area reported by respondents (overall Pearson’s chi-square test=ns).

Main causes of cough	Overall Italy (n=300)	Italian areas
		Northern (n=90)	Central (n=66)	Southern (n=144)
Viral infections	12 (4.0%)	2 (2.2%), p=0.384	8 (12.1%), p=0.002	2 (1.4%), p=0.076
URTIs	62 (20.7%)	20 (22.2%), p=0.876	14 (21.2%), p=0.979	28 (19.4%), p=0.893
LRTIs	33 (11.0%)	9 (10.0%), p=0.554	12 (18.2%), p=0.119	12 (8.3%), p=0.268
Bacterial infections	9 (3.0%)	2 (2.2%), p=0.795	1 (1.5%), p=0.546	6 (4.2%), p=0.255
Allergic rhinitis/asthma	160 (53.3%)	49 (54.4%), p=0.801	27 (40.9%), p=0.284	84 (58.3%), p=0.255
Gastroesophageal reflux	16 (5.3%)	4 (4.4%), p=0.595	4 (6.1%), p=0.737	8 (5.6%), p=0.839
Others	8 (2.7%)	4 (4.4%), p=0.143	0, p=0.178	4 (2.8%), p=0.473

Note: p-values compare the frequency within each area versus the total frequency observed in Italy (hierarchical log-linear model).

Abbreviations: LRTIs, lower respiratory tract infections; ns, not significant; URTIs, upper respiratory tract infections.