FEATURESDefining Menstrual Literacy With the Aim of Evaluating Mobile Menstrual Tracking ApplicationsEschler, Jordan PhD; Menking, Amanda MS; Fox, Sarah PhD; Backonja, Uba PhD, RNAuthor Information Author Affiliations: School of Communication Northwestern University (Dr Eschler), Chicago, Illinois; Information School, University of Washington, Seattle (Ms Menking); Department of Communication, University of California, San Diego, La Jolla; and Human Centered Design & Engineering, University of Washington, Seattle (Dr Fox); and Nursing & Healthcare Leadership, University of Washington, Tacoma; and Biomedical Informatics & Medical Education, University of Washington School of Medicine, Seattle (Dr Backonja). The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Corresponding Author: Jordan Eschler, PhD, School of Communication Northwestern University, 710 N Lake Shore Dr, 15th Floor, Abbott Hall, Chicago, IL 60611 (email@example.com). Online date: September 13, 2019 CIN: Computers, Informatics, Nursing: December 2019 - Volume 37 - Issue 12 - p 638-646 doi: 10.1097/CIN.0000000000000559 Buy Metrics Abstract For the estimated 75 million people in the United States who menstruate, understanding menstrual health as a critical “vital sign” is an important aspect of managing personal health. Unsurprisingly, in the past decade, menstrual tracking applications have become increasingly popular, with more than 300 applications available for download and an estimated 200 million downloads worldwide. This study had two purposes. The first was to formulate a definition for menstrual literacy—a baseline of knowledge and skills for understanding anatomical and biological facts of menstruation, caring for the menstruating body, and completing menstrual care tasks—by building on prior work about health literacy and by conducting content analysis of eight Web sites containing information about menstruation. The second was to evaluate a maximum variation sample of 17 menstrual tracking applications; here, features and functions related to the concepts about menstrual literacy identified in a content analysis were compared. These applications had insufficient support for facilitating menstrual literacy, especially for teen and perimenopausal users. The article discusses these disconnects and subsequent design opportunities for menstrual tracking applications to facilitate more robust support of menstrual literacy and overall health of people who menstruate. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.