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Comparison of Menstrual Pictogram Scoring to the Validated Alkaline Hematin Assay as Techniques for Measuring Blood Loss on Feminine Hygiene Products

2010; Elsevier BV; Volume: 17; Issue: 6 Linguagem: Inglês

10.1016/j.jmig.2010.08.465

1553-4669

Patrick E. Burnett, S. Chudnoff, L Turner, D. Dadgar,

Uterine Myomas and Treatments

Study Objective: To invalidate Menstrual Pictograms (MP) for measurement of menstrual blood loss (MBL) on feminine hygiene products. Design: Prospective experimental analysis. Control Samples: Measured volumes of blood were applied to Kotex pads or Tampax tampons. The MP (G. Warrilow et al. The Obstetrician & Gynecologist 2004;6:88-92) score was recorded and compared to actual volumes. Clinical Samples: Patient feminine hygiene samples were scored using the MP and results were compared to a fully validated AH assay proven accurate and precise. Setting: Bioanalytical laboratory, Shawnee Kansas. Patients: One hundred sixty-six patients enrolled or screening for a clinical trial evaluating laparoscopic ablation of uterine fibroids. Measurements and Main Results: In control samples, blood volumes up to 2-fold in difference produced similar-size spots and the same MP score. Pictograms exhibited ceiling effect, underestimating volume between 1.5 and 12 fold. In clinical samples, total cycle MBL from the MP was accurate (within +15% of AH assay) in only 17% of patients (4/23). The MP overestimated MBL by more than 15% in 4% of patients (1/23) and under underestimated MBL (up to 68%) in 78% of patients (18/23).Tabled 123 Patient Total Cycle Volumes MP Vs AH AssayMP Vol (mL)AH Vol (mL)%aNotes2414.961f2148.0-56g5664.9-14e8574.514b,e54.593.5-42c,g3898.1-61c,g95108-12e1111110e79118-33c,g89.5132-32g123160-23d,g88163-46d,g119197-40d,g69202-66d,g103233-56d,g85247-66d,g127301-58d,g175315-44g273403-32g298419-29g176454-61g150462-68d,g164478-66ga % = (MP Vol - AH Vol) x100/AH Vol; b,cAt 80 mL clinical menorrhagia threshold, MP score yields 4.3% false positiveb (1/23) and 13.0% false negativesc (3/23). dAt 160 mL study inclusion criterion, MP yields 34.8% false negatives (8/23). eMP Vol within 15% of AH Vol in 17% of patients (4/23); fMP Vol Overestimated >15% of AH Vol in 4% of patients (1/23); gMP Vol underestimated >15% of AH Vol in 78% of patients (18/23). Open table in a new tab a % = (MP Vol - AH Vol) x100/AH Vol; b,cAt 80 mL clinical menorrhagia threshold, MP score yields 4.3% false positiveb (1/23) and 13.0% false negativesc (3/23). dAt 160 mL study inclusion criterion, MP yields 34.8% false negatives (8/23). eMP Vol within 15% of AH Vol in 17% of patients (4/23); fMP Vol Overestimated >15% of AH Vol in 4% of patients (1/23); gMP Vol underestimated >15% of AH Vol in 78% of patients (18/23). Correlation of the MP to AH volume was 0.789. Mean blood volumes measured (AH assay) in samples from 166 patients exceeded maximum pictogram scores (12 mL/tampon, 15 mL/pad) in 27% of pad samples and 25% of tampon samples. Conclusion: The Menstrual Pictogram is prone to error, does not meet established bio-assay accuracy standards and most often underestimates bleeding volume, to increasing degree at higher volumes more relevant to establishing menorrhagia. It exhibits ceiling effect, and correlates poorly to the validated AH assay. Substantially different blood volumes applied to pads or tampons produce the same image and score, making the pictogram effectively impossible to validate. A validated Alkaline Hematin method is the preferred means to measure MBL in clinical trials of menorrhagic conditions.