survival it remained significant for haplotype 6A-1A (P = 0.029, OR = 2.45; 95% CI 1.10 to 5.46), although for 6A 12 haplotype it was not significant (P = 0.072); for 90-day survival it was significant for both 6A 3 (P = 0.038, OR = 0.52; 95% CI 0.28 to 0.96) and 6A-1A (P = 0.045, OR = 2.12; 95% CI 1.02 to 4.44) haplotypes. No effect of the SFTPD aa11 SNP was observed. Due to the high number of observed haplotypes, and because of the limited sample size in the patient groups when they were stratified on the basis of severity and outcome, the haplotypes including SFTPA1, A2 and D were not studied.