6-Minute Walk Test

In a METS substudy of 545 participants, shorter preoperative 6MWT distance was significantly associated with major complications (OR 1.32 per 100 m decrease, 95% CI 1.01–1.73). The 6MWT is acceptable to patients across a wide functional range and demonstrates excellent reliability, validity, and safety even in high-risk populations. Prior studies of the 6MWT in surgical populations have produced inconsistent findings regarding its association with postoperative complications. The METS substudy was underpowered and may have been affected by selection bias, as nearly half of participants had completed CPET before the 6MWT on the same day. In the FAST Walk study a single 6MWT administration is performed, consistent with guidelines for prognostic use rather than repeated testing. Clinicians are blinded to 6MWT distance; only safety-related termination events, not the walk distance, are disclosed to the surgical team. In the METS-6MWT substudy, early termination of the 6MWT occurred in only 1% of participants and no adverse events were observed. The 6MWT is a simple field walking test requiring only a pulse oximeter and blood pressure cuff.