Importance of valid, reliable, and responsive outcome measures for lumbar spinal stenosis

Outcome measures in medical research are the tools or assessments used to collect the data relevant to patients or clinicians [1]. The component of a patient’s health status being assessed will depend upon the condition and the priorities of the patient and clinician. For lumbar spinal stenosis (LSS) the most common domains of assessment include patient-reported outcome measures (PROMS), such as disability (eg, Oswestry Disability Index), pain, quality of life, and clinician and performance outcome measures, such as observed function (eg, 6-minute walk test) and adverse events [1]. All medical research relies upon outcome measures being of sufficient quality to capture what they intend to. To determine the quality of an outcome measure, we can look at its measurement properties [2]. A systematic review published in The Spine Journal in 2019 found that the majority of functional outcome measures for LSS had either inadequate or unknown measurement properties [3].