High Impact Chronic Pain (HICP) is defined as the presence of pain on at least half of days in the previous 3-6 months with substantial restriction of functional participation in work, social, and self-care activities. HICP is assessed with several questions assessing the duration, frequency, and impact of chronic pain, as well as one question regarding the impact of pain on work. In the PMC3, those who report pain on most days for the past 3 months, and who report that pain limits their life or work activities, are considered to have HICP.