Measuring waterpipe tobacco smoking in survey research.

Waterpipe tobacco (WT) smoking remains a significant public health problem. However, few validated measures exist, presenting challenges for obtaining accurate prevalence estimates and making comparisons across studies. We identified items used to measure several WT smoking behaviours in eight US national surveys of youth and adults and two international studies, including the National Youth Tobacco Survey, National Adult Tobacco Survey, Population Assessment of Tobacco and Health Adult and Youth Surveys, Monitoring the Future, National Health Interview Survey, Health Styles, Tobacco Use Supplement: Current Population Survey, Global Adult Tobacco Survey and Global Youth Tobacco Survey. We also identified WT survey items across the first 14 Food and Drug Administration-funded Tobacco Centers of Regulatory Science. Constructs included product description and terminology, ever and current use, quantity and frequency, use of flavours and reasons for use. There was little consistency in WT measurement, highlighting the need for validated measures.