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Table 2 Effectiveness primary and secondary outcome measures

From: Sahaj Samadhi Meditation versus a Health Enhancement Program for depression in chronic pain: protocol for a randomized controlled trial and implementation evaluation

Outcome measure


Primary: change in nine-item Patient Health Questionnaire (PHQ-9) scores from baseline to 12-week follow-up and 24-week follow-up (continuous)

The PHQ-9 is a well-validated and widely used self-report scale used in depression and chronic pain clinical care and research. Reduction in a continuous outcome score is a more sensitive test than percent reduction in scores that have been reported in some depression studies [5, 45, 46]. A self-report scale is more feasible than an assessor-rated scale (e.g., Hamilton Depression Rating Scale (HAM-D17)) given the site characteristics

Secondary A: change in Brief Pain Inventory (BPI) from baseline to 12-week follow-up and 24-week follow-up (continuous)

The BPI is a validated self-report scale used in pain trials and clinical pain practice and is a core outcome measure per the IMMPACT recommendations [47]. Two independent measures are included—pain severity and pain interference with function—and both are clinically relevant outcomes

Secondary B: change in opioid dosage (reported in total daily morphine equivalents) from baseline to 12-week follow-up and 24-week follow-up (self-reported; continuous measurement with conversion to total daily morphine equivalents using standardized conversion tables)

Self-report of opioid dose via patient log is the most common measure of opioid use in clinical research trials [48]. Given that patients are on a variety of distinct opioids and that some patients may be on >1 formulation, there is a need for common reporting as provided by morphine equivalent doses

Secondary C: change in health-related quality of life (QoL; by the 36-item Short Form survey (SF-36)) from baseline to 12-week follow-up and 24-week follow-up (continuous measurement)

The SF-36 has been validated as a quality QoL measure in the chronic pain population and is recommended by IMMPACT [49]. It is included here as a secondary outcome with expected positive findings from pilot data collected in other meditation interventions, which demonstrate moderate-to-large effect sizes [50]. This measure is well-aligned to the intervention which is designed as a means of improving overall QoL more than as a disease treatment