Table 9. Frequency of reporting statistically significant factors of improved survival.

Characteristic	HSCT	IST
Age (years): young vs. advanced	5 [34], [35], [37], [39], [52]	2 [38], [52]
Age (years): advanced vs. young	0	3 [34], [37], [51]
PMN (G/L): <0.2 vs. 0.2 to <0.5	1 [34]	1 [42]
PMN (G/L): 0.2 to <0.5 vs. <0.2	0	5 [34], [38]–[40], [51]
Year of treatment: recent vs. earlier period	4 [35], [51], [52], [54]	1 [54]
Type of IST: ALG+CSA vs. ALG	n.a.	2 [35], [52]

Abbreviations: ALG: anti-lymphocyte globulin; CSA: cyclosporine A; HSCT: hematopoietic stem cell transplantation; IST: immunosuppressive therapy; n.a.: not applicable; PMN: polymorphonuclear neutrophil granulocytes.