Screening
Carpal Tunnel Syndrome Severity Questionnaire: Diagnostic Accuracy Maik Zannakis* Maik Zannakis
Background America’s high incidence of carpal tunnel syndrome (CTS) is likely vastly underreported. Since CTS is a progressive disorder, early diagnosis is crucial for proper management. Symptoms questionnaires have been used for remote diagnoses, but heretofore have been fraught with inaccuracies. This study assesses the diagnostic accuracy of a new Carpal Tunnel Syndrome Severity Questionnaire (CTSSQ) when used as a tool to classify CTS severity.
Methods Screening data were collected via phone and email. The data were specific to CTS symptoms, results of EMG and NCV studies, and physician diagnostic impressions. Included patients demonstrated one of the three CTS severity levels (AAFP scale of Mild, Moderate, Severe). These patients then completed a CTSSQ online (N=68). Their prospective CTSSQ data were compared to pre-screen data. Diagnostic accuracy was evaluated for CTS severity level, comparing both sum- and algorithm-based scores.
Results For Mild CTS, the optimal cut-off score was 33 (sensitivity 88%, specificity 90%, AUC of 0.79). For Moderate CTS, the optimal cut-off score was 69 (sensitivity 91%, specificity 93%, AUC of 0.83). For Severe CTS, the optimal cut-off score was 91 (sensitivity 94%, specificity 96%, AUC of 0.85). The positive predictive value of the CTSSQ algorithm for diagnosing Mild, Moderate, and Severe levels of CTS was 89%, 91%, and 93%, respectively.
Conclusions The CTSSQ algorithm-based score performs well in identifying those patients with CTS as compared with similar measuring instruments. The more severe the CTS, the better the diagnostic validity of the tool for identifying the level of severity. Validating the diagnostic accuracy of the tool helps patients heretofore undiagnosed with CTS better comprehend their level of severity, with the intent of providing more impetus to seek immediate treatment.