The reproducibility of urodynamic studies of neurogenic bladders in spinal cord injury

To evaluate the reproducibility (test-retest reliability) of urodynamic studies in neurogenic bladders of subjects with spinal cord injuries (SCI).

Retrospective case series.

Urology department of a major rehabilitation center.

Fifty individuals with SCI who had urodynamic studies performed from February 2000 to April 2000.

Two trials (Time 1 and Time 2) of urodynamic studies done 5 minutes apart, with the following collected: bladder volume at first sensation, maximum cystometric capacity, presence of uninhibited contractions, opening pressure, maximum detrusor pressure, duration of bladder contraction, volume voided, and post-void residual (PVR) volume. The corresponding data were then compared. Statistical analysis was performed using the Lin's concordance correlation coefficient and kappa.

Analysis of the data showed statistically significant levels of agreement between Time 1 and Time 2 with regard to the various corresponding parameters for both the filling and voiding phases. For 3 of the most important parameters-the opening pressure, maximum detrusor pressure, and duration of contraction-the Lin's concordance correlation coefficient (r(c)) was .86 (95% CI, .78-.95; p < .0005), .91 (95% CI, .86-.96; p < .0005), and .97 (95% CI, .95-.99, p < .0005), respectively.

The study demonstrates good short-term intrasubject reproducibility of urodynamic studies in individuals with SCI.