Reliability of Likert Scale for Surgeon-Rated Conspicuity of Ureters with Pudexacianinium Chloride (ASP5354).

Background: Pudexacianinium chloride is a novel near-infrared fluorescence (NIR-F) imaging agent under evaluation for ureter visualization in patients undergoing abdominopelvic surgery.

Methods: Surgeons were trained to use the Likert scale. Each surgeon rated 36 color image pairs (white light and NIR-F on the same anatomical area) from the phase 2 trial (NCT04238481), in which adults undergoing abdominopelvic surgery received single doses of pudexacianinium. Surgeons rated a single-item question, "How conspicuous is the ureter?" using a 5-point Likert scale ranging from 1 = none (not self-evident) to 5 = excellent (extremely self-evident). Images were taken at the beginning (10-30 minutes postpudexacianinium, n = 18 pairs), middle (between 30 minutes postpudexacianinium and end of surgery, n = 13 pairs), and end of surgery (n = 5 pairs) and were displayed for 30 seconds. Inter-rater reliability at baseline and intra-rater reliability after 1 week from baseline were evaluated using intraclass correlation coefficients (ICCs) with target values set a priori as 0.70 and 0.80 for inter-rater and intra-rater reliability, respectively.

Results: Seventeen surgeons were enrolled and completed baseline ratings; 15 completed retest ratings. Mean (standard deviation) rating on the 5-point Likert scale with NIR-F was 3.77 (0.98) at baseline and 3.84 (0.97) at retest and 2.28 (0.98) at baseline and 2.16 (0.95) at retest with white light. Inter-rater reliability ICC was 0.70 (95% confidence interval [CI] = 0.63, 0.78) and intra-rater reliability ICC was 0.82 (95% CI = 0.80, 0.84).

Conclusions: The 5-point Likert scale had adequate inter- and intra-rater reliability among surgeons for assessing ureter conspicuity in patients who received pudexacianinium during abdominopelvic surgery.