Establishing the Patient Acceptable Symptoms State for the Boston Carpal Tunnel Questionnaire in a Postoperative Carpal Tunnel Surgery Population.

Purpose: Threshold scores for patient acceptable symptom state (PASS) represent the score beyond which a patient considers themselves "well." We aimed to determine PASS thresholds for the symptom severity scale (SSS) and functional status scale (FSS) of the Boston Carpal Tunnel Questionnaire in a sample of patients 1 year following carpal tunnel release.

Methods: Adults (≥ 18 years) from a single, tertiary-care academic institution were contacted 12 ± 1 months after carpal tunnel release. The Boston Carpal Tunnel Questionnaire and two PASS anchor questions were administered via REDCap-one queried acceptability of their current symptoms, and the other queried function. Participants were classified as being in an acceptable symptom state ("PASS(+)") if they answered "very satisfied" or "somewhat satisfied," whereas those responding "neither satisfied nor dissatisfied," "somewhat dissatisfied," or "very dissatisfied" were classified as "PASS(-)." Threshold values were calculated using three methods: (1) the mean score for PASS(+) participants, (2) the 75th percentile score for PASS(+) patients, and (3) the Youden Index determined using receiver operating curve (ROC) analysis to maximize sensitivity and specificity.

Results: The 153 patients included in the study had a mean age of 60 ± 15 years and 60% (94/153) were women. At a mean follow-up of 1.0 ± 0.1 years, SSS and FSS scores were significantly lower (better) for PASS(+) than PASS(-) patients for both anchor questions. PASS estimates ranged from <1.4 to <1.8 for the SSS and from <1.3 to <1.5 for the FSS. All ROC curves produced excellent discrimination (area under the curve > 0.8).

Conclusions: We propose PASS thresholds of 1.8 for the SSS and 1.5 for the FSS, derived by the Youden or ROC method, which showed excellent discrimination between PASS(+) and PASS(-) patients.

Clinical relevance: These threshold values can be used to assess whether patient populations have achieved an adequate symptom and functional state.