TCM Preservación de la Salud para la Depresión (TCMHPFD)

The participants in the traditional Chinese medicine health preservation group will attend six traditional Chinese medicine health preservation courses (2h each per one, for 6 weeks) to learn and experience traditional Chinese medicine health preservation from a registered traditional Chinese medicine practitioner in a classroom at the School Nursing, the Hong Kong Polytechnic University.

Each class will be conducted in a small group of 4 to 6 participants to enhance interaction and ensure the quality of teaching. Participants will then practice traditional Chinese medicine health preservation at home for 6 weeks.

The traditional Chinese medicine health preservation intervention for depression was developed based on a previous systematic review and meta-analysis of Traditional Chinese medicine based integrated health interventions for depression, traditional Chinese medicine health preservation textbooks, clinical practice guidelines related to traditional Chinese medicine health preservation and traditional Chinese medicine treatment for depression. The content and structure of traditional Chinese medicine health preservation for depression was achieved among Hong Kong traditional Chinese medicine experts via a Delphi study.

Usual care

Participants in the waitlist control group will receive usual care during the 6-week waitlist period of intervention, and 6-week waitlist period of follow-up. After the follow-up assessment, they will be provided an equivalent traditional Chinese medicine health preservation for depression.

The PHQ-9, a self-rated questionnaire to assess the presence and severity of depressive symptoms of an individual during the last 2 weeks on a scale of 0 (not at all) to 3 (nearly every day), with a total score ranging from 0 to 27. A higher score indicates a higher severity of depression symptoms.

The GAD-7 is a four-point Likert scale for identifying probable cases of GAD and assess the severity of symptoms of GAD for the past 2 weeks. The total score of GAD-7 varies from 0 to 21, and responses include "nearly every day," "more than half the days," "several days", and "not at all". The cutoff point of 5, 10, and 15 of GAD-7 might be interpreted as showing mild, moderate, and severe levels of anxiety. Higher scores indicate more severe GAD symptoms.

The PSS-10 is a 10-item scale that is often used for measuring perceived psychological stress. Each item is rated on a 5-point Liket scale during the past month, referring to "4" as "very often" and "0" as never. The total score changes from 0 to 40, with a higher score meaning a higher perceived psychological stress level.

The ISI is a seven-item self-rating scale to assess the severity of insomnia, distress, and functional impairment associated with insomnia on a 5-point Likert scale. The score of each item of ISI ranges from 0 (no problem) to 4 (very severe problem), and the total score is interpreted as below: absence of insomnia as 0 to 7, sub-threshold insomnia as 8 to14, moderate insomnia as 15 to 21, and severe insomnia as 22 to 28.

The FAS is a 10-item scale that evaluates symptoms of chronic fatigue with a five-point Likert-type scale, which ranges from 1 ("never") to 5 ("always"). A higher score means greater fatigue severity. The total score ranges from 10 to 50. A total FAS score < 22 means no fatigue, a score≥ 22 refers to fatigue.

The SF-6D covers six domains using a scale of 1 to 6 to evaluate participants' general health and quality of life. Higher scores indicate better health status.

The GSE scale is a four-point Likert scale with ten items appropriate for evaluating an individual's self-efficacy. It is scored ranging from 1 point to 4 points, referring to "not at all true" to "exactly true" and the total score varied from 10 to 40. A higher score shows a more satisfactory self-efficacy.

The HPLP II is a scale with 52 items and 6 domains for measuring health-promoting behavior, defined as a multidimensional pattern of self-initiated perceptions and actions that serve to maintain or increase the level of self-actualization, wellness, and fulfillment of a person. The total scores of HPLP-II varies from 52 to 208. Higher HPLP II score denotes better level of health-promoting lifestyle.

The CEQ is a self-reported scale with 6 items and two subscales of treatment credibility and outcome expectancy to measure the participants' treatment credibility and outcome expectancy for improvement. The final scoring of the CEQ is computed by the sum of the items composing each subscale, with a higher quotation referring to higher treatment credibility and outcome expectation.

The CEQ taps on participants' affective and cognitive evaluations of treatment satisfaction, credibility, and expectation. The subscale of credibility assesses beliefs about the treatment strength. The expectancy subscale assesses how participants perceive their symptoms will improve during the intervention period.