Disability patterns in multiple sclerosis: A meta-analysis on RAW and PIRA in the real-world context.

PIRA accounts for most events causing disability accumulation in the real-world setting, even at the earlier disease stages, whereas RAW represents a less frequent phenomenon, likely due to effective treatments. The detection and statistical analysis of PIRA outcomes pose challenges, raising the risk of erroneous inference. When interpreting our findings, caution is needed given the wide heterogeneity of included studies.