Development and Initial Validation of the Menstrual Sensitivity Index

The Anxiety Sensitivity Index is a widely-used measure to assess anxiety sensitivity (i.e., the fear of anxiety and its associated symptoms). More recently, researchers have developed disease-specific measures assessing sensitivity to specific symptoms. To assess sensitivity to menstrual symptoms, we developed and evaluated the reliability and initial validity of the Menstrual Sensitivity Index (MSI), a modification of the Visceral Sensitivity Index. The MSI consists of 10 items rated on a 6-point Likert scale from 1 (“strongly agree”) to 6 (“strongly disagree”). Items assess respondents’ menstrual symptom-specific anxiety (e.g., fear and anxiety induced by menstrual pain, the thought that menstrual pain is a sign of other problems, etc.). Items are reverse scored and re-coded on a 0 to 5 scale. Total scores are calculated by summing all item responses; higher scores indicate more severe menstrual-specific anxiety. Participants included 1,160 women ages 18-55 years (mean=34.6, SD=9.5) who completed an online survey. Average menstrual pain was rated on a 0 (no pain) to 10 (worst pain possible) Numeric Rating Scale; enrollment was stratified such that 14.8% of participants rated their menstrual pain as 0-2, 59.7% rated 3-7, and 25.4% rated 8-10. All participants had self-reported regular menstrual cycles over the previous 12 months. Internal consistency was calculated using Cronbach's alpha, and initial validity was assessed using Pearson bivariate correlations. The MSI demonstrated excellent internal consistency (alpha=0.942). Scores were positively correlated with measures of average menstrual pain, menstrual symptoms, non-menstrual bodily pain, anxiety sensitivity, and pain catastrophizing (R's from 0.39-0.65; all p's<.001). Results indicate that the MSI demonstrates convergent validity with measures of similar constructs. The moderate strengths of the correlations also indicate some divergence, meaning that the MSI may assess a distinct construct relative to the other measures. Future research is needed to assess the test-retest reliability, factor structure, and other psychometrics. NIH/NICHD grant R01HD093680.