MARX was developed in 2001 as an patient-reported outcome measure with the goal of finding a patient’s general level of activity.
MARX focuses on four activity points: running, deceleration, cutting (changing directions while running), and pivoting. Patients are asked to indicate approximately how many times in the past 12 months they performed each of these activities while at their healthiest and most active state. The four knee functions are rated on a 5-point scale of frequency and scores are added up to a maximum of 16 points with a higher score indicating more frequent participation.
The MARX rating scale is different from most previous measures of activity because it’s not based on participation in specific sporting activities. Instead, patients are asked about different components of physical function (e.g. running and pivoting) that are common to different sports.
The key strength of the MARX activity rating scale is that it may be self-administered and takes approximately one minute to complete. The measure also asks patients about issues that are speciﬁcally relevant to them, such as giving way, pain, locking of the knee, and ability to run. In addition, studies have shown that there’s moderate correlation between the MARX and the Tegner Activity Scale (TAS).
There is a concern that the MARX rating scale does not adequately differentiate between patients that remain active in non-knee aggravating activities and those that give up sports entirely, creating a possible floor effect that requires investigation.
Additionally, despite rigorous development processes, more studies need to be carried out highlighting the psychometric evidence for the MARX scale which should include a comprehensive analysis of clinical usefulness, reliability, validity, and responsiveness.
The MARX PRO Measure does not require a licence and is free to use.
About CODE Technology
As we transition into value-based care, collecting patient-reported outcomes (PROs) has never been more important. But the process can be intimidating. That’s where CODE Technology comes in. We’re a PRO vendor that handles everything every aspect of PRO data collection for you as a service, 100% out of office. We collect, we report, we benchmark, and the data we collect assists with research, helps improve patient care, and gives leverage in negotiations with payers.
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