The Committee discussed the decision problem framework and in particular the major outcomes that were considered. The Committee was concerned that joint outcomes had not been included in the decision problem. It noted, however, that the main trials for total hip and total knee replacement did not evaluate joint outcomes. The Committee also noted that fondaparinux was not included in the manufacturer's decision problem, although the NICE guideline on venous thromboembolism: reducing the risk of venous thromboembolism in inpatients undergoing surgery (replaced by the NICE guideline on venous thromboembolism in over 16s) recommended that in addition to mechanical prophylaxis, people at increased risk of VTE and people undergoing orthopaedic surgery should be offered LMWH. The guideline also recommended that fondaparinux, within its licensed indications, may be used as an alternative to LMWH. The Committee noted that the manufacturer had not included fondaparinux as a comparator because it was used in less than 2% of patients in current UK clinical practice. The Committee noted comments from clinical specialists that drugs for the prevention of VTE are not routinely used by all orthopaedic surgeons because of concerns that they may increase the incidence, or worsen the consequences, of wound haemorrhage in the site of the orthopaedic surgery.