Project Summary/Abstract Non-specific/non-pharmacologic therapeutic effects can improve health outcomes, however, little is known about how to maximize these effects, particularly for effects related to patient-clinician interactions. These effects are especially important in treating chronic pain. Preliminary studies indicate that both increased visit length and augmented visit content (designed to elicit a holistic understanding of the individual) enhance non- specific effects related to patient-clinician interactions, but it is unclear which of these factors is more important or if their interaction is synergistic. This proposal’s long-term goal is to advance the science of non-specific therapeutic effects related to patient-clinician interactions to improve health outcomes. Its objective is to quantify the relative effects of, and mechanisms by which, increased visit length and augmented visit content affect patient-clinician interactions and health outcomes in knee osteoarthritis (OA). Knee OA is an ideal condition for studying the effects of visit length and content on patient-clinician interactions and health outcomes because it is a leading cause of chronic pain and disability in older adults, many common treatments have poor safety profiles, and clinical trials of medications for knee OA suggest that non-specific therapeutic effects account for a major component of treatment effects. The central hypothesis is that both increased visit length and augmented visit content will increase the non-specific treatment effects associated with diclofenac gel (a standard topical treatment for knee OA-related pain). Project specific aims are: 1) To determine whether increased visit length and/or augmented visit content increase the non-specific treatment effects of diclofenac gel on knee OA pain and function; 2) To determine how visit length and content affect patient and clinician behaviors and physiology during patient-clinician interactions; and 3) To determine whether patient COMT genotype modifies the effects of increased visit length and augmented visit content on knee pain. The approach is innovative in that there are few randomized trials targeting non-specific effects associated with patient- clinician interactions, and none that directly test the effects of visit length and content on health outcomes or use physiologic measures to assess patient-clinician interactions. The proposed study is significant because it will determine the relative contributions of visit length and content on health outcomes in knee OA and advance understanding of potential clinical, behavioral, physiologic, and genetic mechanisms through which non- specific effects impact health outcomes. This project advances a line of research focused on improving outcomes in knee OA by developing and testing strategies to modify clinical care delivery to maximize non- specific therapeutic effects associated with patient-clinician interactions. It will also help develop new rese...