A global health NGO has suggested more rigorous research to address menstruation-related issues among school-going girls including hearing their voices and discussing about their needs, claiming that a majority of girls skip school when they have their periods. "The relationship between menstruation and girls' attendance in schools is a critically important research issue. We have seen that poor sanitation systems and lack of information on proper disposal, along with inadequate hand- washing and waste disposal bins are barriers to limit a girl's ability to manage menstruation in school in India," senior program officer of PATH (Devices and Tools) Nancy Muller told media persons. "At a global level, studies linking use of effective menstrual care products and girls' school attendance have generated varied results. Scale and quality of research have been significant constraints," she said, stressing that voices of girls should be included while designing these systems.