5 Future directions

The systematic review for this module found adequate evidence to confirm that anaemia is an independent predictor of poorer patient outcomes. However, the findings did not prove that anaemia causes these outcomes, or that correction of the anaemia will reverse the outcomes. Since aetiological questions cannot give rise to recommendations, further investment in systematic reviews in this area is unwarranted.

There was surprisingly little evidence for the benefit of RBC transfusions to correct anaemia in both general and specific medical populations. Thus, it has been difficult to provide guidance on RBC transfusion thresholds while ensuring a patient focus. Any future studies should focus on a formal evaluation of effects on well-being, because this is one of the most common justifications for transfusion. In addition, although there is some evidence of short-term harm associated with transfusion, there is uncertainty about the long-term consequences.