Table 1.

Sample PP interventions that have been tested in medical populations

Intervention	Description
PP combined with other techniques to target health behavior change
Positive affect and self-affirmation induction and behavioral contracting for management of hypertension (Boutin-Foster et al., 2016)	At an introduction session, participants were taught a positive affect induction strategy to help them focus on positive thoughts that make them feel good throughout the day, and a self-affirmation strategy to think of core values that made them proud whenever they encountered a situation that would make it difficult to adhere to medications. The intervention also included provision of a workbook about hypertension, setting a behavioral contract about hypertension medication adherence, and utilizing motivational interviewing for medication adherence. Participants received follow-up calls every other month to review progress.
Positive psychotherapy for smoking cessation counseling (Kahler et al., 2014)	Six sessions of PP-based psychotherapy that consisted of three good things, gratitude letter, savoring, active-constructive responding, savoring acts of kindness, and using personal strengths. This was combined with standard behavioral smoking cessation counseling that included setting a quit date, problem-solving to manage triggers, and related strategies.
Positive psychology-motivational interviewing for physical activity promotion in people with recent acute coronary syndrome (Huffman et al., 2019)	Twelve weekly phone sessions with a written manual and assigned homework between sessions. PP topics included gratitude for positive events, a gratitude letter, capitalizing on positive events, past successes, using personal strengths, acts of kindness, enjoyable and meaningful activities, and an optimism exercise. The intervention also included motivational interviewing and goal-setting for physical activity each week.
PP-alone interventions
Positive affect intervention for people newly diagnosed with HIV (Moskowitz et al., 2017)	Five in-person sessions and one phone session in which participants learned eight behavioral and cognitive skills for increasing positive affect: noting daily positive events, capitalizing on or savoring positive events, gratitude, mindfulness, positive reappraisal, focusing on personal strengths, setting and working toward attainable goals, and small acts of kindness. They were assigned home practice to use skills between sessions.
Humor training for patients with chronic pain (Kugler et al., 2021)	Four in-person humor training sessions for hospital inpatients with chronic pain in Germany. Topics included encouraging expression of joy and cheerfulness via laughter, teaching positive effects of humor, fostering ability to see situations in humorous ways, and overcoming negative emotions that hinder humor.
Promoting resilience in adolescents and young adults with cancer (Rosenberg et al., 2021)	Four one-on-one in-person session that focused on managing stress, goal-setting, positive reframing, and meaning making.
Optimism training intervention in patients with heart disease (Mohammadi et al., 2018)	Eight in-person group sessions that utilized 17 PP exercises aiming to promote optimism (e.g., acknowledgement and positive interpretations of the cardiac event, positively reframing life events, three good things, best possible self).