Taking the word of patients with peripheral artery disease (PAD) on whether they can walk farther after an exercise program is likely to significantly underplay the benefit of the intervention, a US study suggests.

This effect could be important, particularly in trials comparing revascularisation with exercise that use patient-reported outcomes, the authors caution.

Researchers from Chicago pooled results from three trials in 400 patients with PAD who were randomised to either a walking exercise program — supervised or at home — or to merely attending a health lecture.

Objectively, exercise was demonstrably beneficial, with the mean six-minute walk distance (343m at baseline) improving by 39.8m more in the pooled exercise study arms than in the control group at six-month follow-up.