Comparative Effectiveness Study of Two Forms of Ketamine for Treatment-resistant Depression

Score on the Montgomery-Asberg Depression Rating Scale (MADRS). The MADRS is sensitive to change, and is commonly used for treatment trials in depression. See outcome 1 for minimum and maximum values, and whether higher scores indicate a better or worse outcome.

Response (≥50% improvement in MADRS)

Remission (MADRS score ≤10)

Depression, Anxiety and Stress Scale (DASS-21) - will be used to measure psychological distress. It consists of three 7-item subscales, with items scored on a 4-point Likert scale (0-3) and summed to obtain subscale scores.

The Clinical Global Impression - Improvement scale (CGI-I) is used to assess depressive symptom improvement from study baseline. The minimum value is -6 (maximum deterioration) and the maximum value is 6 (ideal improvement).

The Clinical Global Impression - Severity scale (CGI-S) is used to assess depressive symptom severity. The minimum value is 1 (normal) and the maximum value is 7 (among the most extremely ill patients).

Columbia Suicide Severity Rating Scale (C-SSRS) - short questionnaire that will be used by the clinic teams as a clinical tool to assess suicidality.

Speed of response, assessed by number of treatments required to attain CGI-I score of ≥ 3.

Assessed via the Ketamine Side Effect Tool (KSET), designed to monitor the acute, cumulative and longer-term safety of ketamine treatment.

Data collected as an Adverse Event of Special Interest

Bladder Pain-Interstitial Cystitis Symptom Score (BPIC-SS) - a self-report symptom-based instrument that identifies moderate to severe bladder pain syndrome. Side effects of racemic ketamine/Spravato® include inflammation of the bladder endothelium. From 8 questions about bladder/urination pain, patients can score a minimum of 0 (asymptomatic) and a maximum of 38 (severe symptoms).

Cognitive Failures Questionnaire (CFQ) is a self-rated tool to assess subjective impression of cognitive functioning. From 25 questions, patients can score a minimum of 0 (best) and a maximum of 100 (worst).

Ketamine liking/craving score will be used as a measure of ketamine craving/abuse. A visual analogue scale is used, where patients can score a minimum of 0 (strong dislike/no craving) and a maximum of 30 (very strong liking/constant craving).

Assessed via the Ketamine Side Effect Tool (KSET), designed to monitor the acute, cumulative and longer-term safety of ketamine treatment.

An 8-item self-rated instrument to assess the acceptability of healthcare interventions. This evaluates the constructs of affective attitude, effort burden, ethicality, perceived effectiveness, intervention coherence, self-efficacy, opportunity costs and general acceptability. Patients can score a minimum of 8 (very unacceptable) and a maximum of 40(very acceptable).

"If reporting a score on a scale, please include the minimum and maximum values, and whether higher scores mean a better or worse outcome." Appears that not all high scores are positive so makes it hard to address this issue.

Collected via case report form. Captures reason for ceasing, switching or re-starting study medication.

Recovering Quality of Life, 10-item (REQOL-10) is used to assess the quality of life for people with different mental health conditions. Patients can score a minimum of 0 (poorest quality of life) and a maximum of 40 (highest quality of life).

12-item WHO Disability Assessment Scale (WHODAS-12) is a 12-item self-rated assessment of health and disability. It will be used to assess functionality. Patients can score a minimum of 0 (no disability) and a maximum of 48 (complete disability).

Patient Health Questionnaire-9 (PHQ-9) is a self-report screening tool designed to assess the severity of depressive symptoms in individuals and monitors symptom changes and treatment effects over time. Patients can score a minimum of 0 (no depression) and a maximum of 27 (severe depression).

Assessment of Quality of Life Questionnaire (AQoL-8D) consists of 35 items covering 8 dimensions: Independent Living, Pain, Senses, Mental Health, Happiness, Coping, Relationships, and Self-worth. It will be used to assess quality of life outcomes and to facilitate the health economics analysis. There is a max patient score of 1 (perfect health) and a minimum score of 0 (deceased) based on weighted utility scores

The resource use questionnaire (RUQ) collects information regarding the type and number of contacts with the health system including hospitalisations, consultations and medications. The information is then 'scored' by multiplying indicative unit costs by the number of contacts for each service used. The costs per service are summed to calculate a total health sector cost.

The resource use questionnaire also collects information regarding time missed (absenteeism) and time working at reduced capacity (presenteeism) for paid work and time missed from unpaid work. The number of hours missed and working at reduced capacity from paid work will be valued using an average wage rate. The hours missed from unpaid work will be valued using a shadow cost for the value of leisure time. These costs are summed and combined with health sector costs to calculate societal costs.

The Treatment Preferences questionnaire is a simple 3 item self-report questionnaire which asks participants to indicate their treatment preference for one of the 2 interventions, if any; their strength of preference (slight, moderate or strong); their reason for preference (Prefer this method of receiving the medication; Had this treatment before and benefitted; Past negative experience with the other treatment; Impression from reports, other people or media; Other (please specify))

The SETS is a self-report questionnaire that assesses positive and negative treatment expectations with 6 items rated on a 7-point Likert scale from 0 'not agree at all' to 6 'fully agree'; additional questions ask the responder to confirm the treatment they will receive and whether they have received it before as well as whether any specific benefits or harms/negative side effects are expected

The DERS-16 is a self-report measure with established internal consistency, reliability and validity that assesses an individual's typical levels of difficulties in emotion regulation. The DERS-16 assesses five aspects of difficulties in emotion regulation: nonacceptance of emotional responses, difficulty engaging in goal-directed behaviour, impulse control difficulties, limited access to emotion regulation strategies, and lack of emotional clarity.

The LPFS-BF is a 12-item self-report questionnaire that provides a first impression of impairments in personality functioning. The LPFS-BF consists of 12 items, clustered into two higher order domains: self-functioning and interpersonal functioning. Validity and sensitivity have been established in a range of samples and languages

The Quick Inventory of Depressive Symptomatology self-report (QIDS-SR) is a measure of depressive symptom severity. It consists of 16 factors across 9 different criterion domains, with items scored on a 4-point Likert scale (0-3) and summed to obtain subdomain scores.

The Patient Global Impression - Improvement (PGI-I) measures a patient's perception of their improvement since a treatment. It consists of one question that uses a 7-point scale that asks a patient to rate their change ranging from 'very much improved' to 'very much worse'.

The Generalized Anxiety Disorder (GAD-7) is used to assess symptom severity of generalised anxiety disorder. It consists of 7 items that use a 4-point Likert scale (0-3) which are summed to create a total score ranging from 0 (minimal anxiety) to 21 (severe anxiety.