P5 is planned as a prospective observational study, collecting evidence-based perioperative data on patient history and demographics, physical function, cognitive measures, psychological, and biological markers associated with increased pain susceptibility, and psychophysical measures of pain processing.

The study will use daily ecologic momentary assessment (EMA) of physical and emotional parameters, and collect data on perioperative events.

Follow up will occur 3 months and 6 months postoperatively.

Inclusion Criteria:

• Adults age 18-75 who are candidates for major surgery (expected surgery duration >1 hour, and expected overnight admission to the hospital), or having one of the following procedures, even if outpatient (total joint replacement, hysterectomy, inguinal hernia repair, breast surgery, or video-assisted thoracic surgery (VATS)).
• Access to a smartphone

Exclusion Criteria:

• Participants who do not speak English

Patients who are 18 to 75 years of age and candidates for major surgery at Barnes-Jewish Hospital (expected surgery duration >1h, and expected overnight admission to the hospital, or having one of the following procedures, even if outpatient (total joint replacement, hysterectomy, inguinal hernia repair, breast surgery, or video-assisted thoracic surgery (VATS)) will be approached for consent to this study. Participants will be recruited for participation in the study during their initial preoperative visit to the Center for Perioperative Assessment and Planning (CPAP).