Trial of a Positive Psychology Intervention in Major Depressive Disorder

Participants will be randomized to receive the intervention or recollection (control) arm.
They will be randomized by a random-number generator and will be assigned a condition after
receiving baseline questionnaires. The RA/blinded assessor will be blind to the study
condition. The interventionist and subjects will not be blind to the study condition.

Baseline assessments: After consent and eligibility rule outs, subjects will receive
baseline questionnaires to assess hopelessness (BHS46), suicidality (CHRT47), depression
(QIDS-SR48), and positive states (LOT-R,43 GQ-6,44 PANAS45). Then, subjects will be
randomized via random number generator to receive the control or intervention condition.

After completing baseline questionnaires and receiving randomization, subjects in both
groups will have a 20 minute initial in-hospital session ("week #1"), within a week of
anticipated discharge, in which the interventionist will provide a treatment manual specific
to their condition, review the rationale for the initial exercise, and assign the exercise.
The next day, the exercise will be reviewed and an exercise assigned for the next week.
Immediately after completing the exercise, subjects will rate (on a Likert scale of 1-5)
ease of exercise completion, overall utility, and initial impact on hopelessness/optimism,
to assess immediate effects.

After discharge from the hospital, subjects will have five 20 minute weekly phone sessions
("weeks #2-6") with a different exercise used each week (assigned in the same order to all
subjects). The phone sessions will include: (a) review of the prior week's exercise
(including subject ratings of ease and impact as in week #1), (b) discussion of the
rationale and assignment of the next week's exercise via a guided review of the study
manual, and (c) completion of the Clinical Status questions and the Clinical Global
Improvement scale (CGI) to monitor symptoms and improvement. Sessions will be audiotaped and
random sessions reviewed by our PP consultant to ensure fidelity to the intervention (and
that other techniques, e.g., Cognitive Behavioral Therapy, are not used).

Positive psychology (intervention condition)

Exercises. These were selected based on their superior performance in our pre-pilot study
and others' work:

- Gratitude for positive events: Subjects recall three events, small or large, in the
preceding week that were associated with satisfaction, happiness, pride, or other
positive states.

- Gratitude letter: Subjects write a letter of gratitude thanking a person for an act of
kindness; subject may, at their discretion, share the letter with the other person.

- Performing acts of kindness: Subjects are instructed to complete three acts of kindness
in one day. The acts can be small or large, planned or spontaneous, but must be
expressly completed to be kind to another.

- Using personal strengths: Subjects undergo a brief assessment of personal strengths,
then find a new way to use that strength in the next 24 hours.

- Enjoyable and meaningful activities: Subjects complete a series of self-selected
activities that vary between those that bring immediate boosts in mood and those that
are more deeply meaningful.

- Repetition of an exercise previously done.

Recollection (control condition) The recollection condition was selected because it has been
used in a prior study by our team of a phone-based positive psychology intervention and it
was found to be feasible and well-accepted. Each week, subjects will record recent life
events in a manual without describing emotions associated with the events. The nature,
setting, or type of events to be recorded will differ each week to provide variety and
maintain subjects' interest. This will be described as an intervention that may assist with
organization and hone recall of important life events. Also, as an attentional control, it
has a parallel structure to the experimental arm with a treatment manual, weekly exercises,
and weekly calls to review exercises.

Follow-up 6 and 12 week phone call. After completion of the intervention (6 weeks), and then
at 12 weeks, a blinded study research assistant (RA) will call subjects at 6 and 12 weeks to
repeat measures of hopelessness (BHS), suicidality (CHRT), depression (QIDS-SR) and positive
states (e.g., GQ-6, PANAS, LOT-R). Subjects will also be asked to rate their overall
satisfaction with the treatment they received for their cardiac condition (outside of this
study) over the last 6 and 12 weeks on a scale of 1 (excellent) to 5 (poor). We will record
specific times that subjects would prefer to be called (and not to be called) for future
follow-ups, to reduce intrusion on subjects' lives. We will also send a postcard to subjects
reminding them of their upcoming study phone call. The blinded assessor will make 2
follow-up phone calls (at 6 and 12 weeks) to gather information about outcomes. If subjects
would rather complete the questions in written form rather than over the phone, we will send
them a written packet at the time of each follow-up.

Inclusion Criteria:

- Patient admitted to Massachusetts General Hospital inpatient psychiatric unit

- Age 18 and older

- Able to read/write in English

- SI documented on admission OR admission due to a suicide attempt

- Admission diagnosis of MDD (and current major depressive episode), confirmed using
the Mini International Neuropsychiatric Interview (MINI) and inpatient chart review

Exclusion Criteria:

- Psychotic symptoms, as assessed using the MINI and inpatient chart review

- Cognitive disorder, assessed using a six-item cognitive screen developed for research

- Primary admission diagnosis of substance use disorder