Comparing Deaths from Influenza H1N1 and Seasonal Influenza A: Main Sociodemographic and Clinical Differences between the Most Prevalent 2009 Viruses

Table 4

Average differences after matching (H1N1 as exposure).

Variable	Matched difference	𝑡-stat
Pneumonia	0.0804	1.02
Fever	−0.0303	−0.54
Cough	0.1138	1.78
Dyspnea	−0.1318	−2.30
Expectoration	−0.0469	−0.58
Myalgia	−0.0704	−0.91
Rhinorrhea	−0.0560	−0.79
Cyanosis	−0.0117	−0.16
Headache	−0.0210	−2.51
Chest pain	−0.1591	−2.09
Nasal obstruction	0.0512	1.46
Vomiting	0.0212	0.50
Diarrhea	0.0083	0.17
Days from symptoms start to care	0.2744	0.20
Days from care to death	1.8296	1.63
Days from symptoms start to death	1.8925	1.05