Page 30 - EVALUATION OF TREATMENT FOR HEAVY MENSTRUAL BLEEDING by Herman, Malou

Chapter 7
are unsatisfied have a reduction of less than 80% or a PBAC score higher than 80 points (sensitivity scores >90%).
Strength and limitations
The PBAC has not been evaluated as a tool to assess the effectiveness of a treatment before. By combining raw individual patient data of randomised controlled trials we were able to analyse a large patient population. A limitation is that we had to recode the outcome scales for every study to be able to combine them, as most studies reported different outcome measurement scales (e.g. satisfaction scales 3,4 or 5 points).
Interpretation
PBAC is a semi-quantitative measurement tool and is validated for the use of diagnosing heavy menstrual bleeding. A menstruation needs to exceed 150 points on the chart to diagnose HMB, but upto now it was unclear if the score was also associated with a treatment effect. 2 Only Pawar et al. investigated the impact of heavy menstrual bleeding, measured by the PBAC score, on the Qualtiy of life (QoL) and found a positive correlation: The higher the PBAC-score the lower the QoL. 7 However, they only studied baseline scores and did not evaluate scores after treatment. Other studies confirmed the accuracy of the PBAC compared to the alkaline hematin extraction method (gold standard) for the diagnosis of HMB. Higham found that a PBAC score of >100 correlated with 80mL blood loss, the definition for HMB. Janssen et al. recommended a cut-off of 185 points, while Zakherah recommended a cut-off at 150 points. A PBAC score of >150 points is most often used as an inclusion criterion in HMB studies.2-4 Hald et al. explored the subjective perception of bleeding and the inter-individual and intra-individual variation of PBAC and found that women scored their period with normal blood loss if PBAC values were below 130 points. Nevertheless, all these above mentioned studies focused on the amount of blood loss for diagnosing HMB, not on the acceptability of the bleedings for women after treatment.3-5 So these PBAC heights are not comparable to a group of women treated for HMB. How much blood loss after treatment is acceptable for women and how should we measure this? Although PBAC is a diagnostic tool, many studies have used the PBAC to evaluate blood loss after treatment. Remarkable, because it has never been studied for this purpose. So, actually it is not appropriate to base effectiveness conclusions on the PBAC measurement tool. Our study is the first study that investigated the
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