To determine the sensitivity and specificity of a Secondary Progressive Multiple Sclerosis (SPMS) screening tool to support the diagnosis of patients with SPMS in clinical practice

Timely diagnosis of SPMS represents a challenge for clinicians in daily practice. The SPMS screening tool was developed to support early identification of patients who have progressed, or are at risk of progressing, from relapsing–remitting multiple sclerosis (RRMS) to SPMS. A mixed methods approach involving qualitative research with patients and clinicians and regression on data from a large real-world observational study (n=2,791) was used to determine tool content and create the scoring algorithm

MS neurologists in the United States, Canada, and Germany completed the digital tool for up to 10 patients each, for patients with a diagnosis of RRMS, SPMS and those where the clinician suspected transition to SPMS. Receiver Operating Characteristic (ROC) curves were used to determine the sensitivity and specificity of the tool and define the score thresholds that optimally discriminate between RRMS and SPMS diagnoses

20 neurologists completed the tool for 198 patients. Mean scores for patients with SPMS, suspected to be progressing SPMS, RRMS were (69.6 vs 55.2 vs 38.1, p<0.001) respectively. A threshold of ≥58.85 identified patients with SPMS with sensitivity=0.82, specificity=0.84, area under the ROC curve [AUC]=0.904 [95% confidence interval 0.86–0.95]. A threshold of ≤51.80 identified patients with RRMS with sensitivity=0.83, specificity=0.82, while a threshold of ≤53.85 had sensitivity=0.89, specificity=0.76 using the sum of squares and Youden’s J index, respectively (AUC=0.908 [0.87–0.95])

These results demonstrate that the SPMS screening tool was able to differentiate between RRMS and SPMS patients with high sensitivity and specificity and thus also identify patients in transition. These findings support the validity and potential clinical utility of the tool to help recognize early signs suggestive of progressive disease