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

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

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.

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).

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.