An evaluation of the inter-observer and intra-observer variability of the ultrasound diagnosis of polycystic ovaries.

BACKGROUND

This prospective observational study was undertaken to evaluate the reliability and consistency of ultrasound diagnosis of polycystic ovarian syndrome (PCOS).

METHODS

Eighteen women with clinical and biochemical features suggestive of PCOS and nine normal control women underwent transvaginal ultrasound scan by a single ultrasonographer. The 27 ovarian scans were video-recorded and the recordings were later edited and arranged randomly so that each record appeared twice at random on the tape producing a total of 54 ovarian scans. Four experienced observers independently reviewed the recordings. The observers scored each case as follows: normal, possible polycystic ovary (PCO) and definite PCO.

RESULTS

The mean intra-observer agreement was 69.4% (kappa = 0.54) and the mean inter-observer agreement was 51% (kappa = 0.28).

CONCLUSION

The results suggest that the currently used ultrasonographic criteria for the diagnosis of polycystic ovaries do have significant intra-observer and inter-observer variability and as such must be considered subjective. Transvaginal ultrasonography alone may not therefore be a reliable method of diagnosing or excluding PCOS.