Pictorial blood loss assessment chart in the evaluation of heavy menstrual bleeding: diagnostic accuracy compared to alkaline hematin

Abstract

Background/aims: The pictorial blood assessment chart (PBAC) is a method for evaluation of menstrual blood loss (MBL). This study was conducted to evaluate the accuracy of the PBAC score in diagnosing MBL compared to alkaline hematin as a gold standard.

Methods: Two cohorts were constructed: 30 women who reported 'normal' menses and 170 who reported 'heavy' menses. Evaluation of menstruation was performed using the PBAC score and by alkaline hematin.

Results: Women who reported normal menses were younger (p = 0.071), had lower parity [median parity of 3 (range 1-6) vs. 4 (range 1-12), p < 0.001] and higher hemoglobin levels (11.1 ± 1.1 vs. 10.1 ± 1.6 g/dl, p < 0.001). PBAC scores and MBL by alkaline hematin were significantly correlated (Spearman r = 0.600, p < 0.001). The PBAC score of 150 had a κ of 0.593 (95% CI 0.480-0.687) and an area under the curve of 0.796 (95% CI 0.770-0.821). In a multivariable regression PBAC score >150, presence of blood clots and period duration >7 days were independent predicators of heavy menstrual bleeding with an overall area under the curve of 0.858 (95% CI 0.835-0.879).

Conclusions: The PBAC score is a simple and accurate tool for semiobjective of MBL that can be used in clinical practice to aid the decision about treatment and follow-up.