Table 4

Influence of pulmonary infection during the prevaccine period and chronic respiratory failure on the pneumococcal polysaccharide vaccine 23 vaccine efficacy

Frequency of pulmonary infection during the prevaccine period	Chronic respiratory failure	Vaccinated^*	Unvaccinated^*	p Value^†
(−)	(−)	0.846 (465)	0.836 (629)	0.931
(−)	(+)	0.755 (47)	0.450 (23)	0.019
1 episode	(−)	0.557 (92)	0.490 (55)	0.665
1 episode	(+)	0.431 (17)	0.333 (3)	0.876
>1 episode	(−)	0.317 (22)	0.214 (13)	0.200
>1 episode	(+)	0.000 (3)	0.250 (4)	0.093

↵* Data represented the pulmonary infection-free survival (%) at the end of the study (2 years after pneumococcal polysaccharide vaccine 23 vaccination). Numbers in parentheses indicate numbers of patients.
↵† Data were analysed using the logrank test.