Motivational Interviews Adapted to Improve Depression Treatment in Primary Care

Setting Denver Health is an integrated healthcare system. During the time period that the trial was conducted, 2010 to 2012, Denver Health comprised eight federally qualified community health facilities serving primarily uninsured and Medicaid patients in Denver, Colorado, USA. The mainstay treatment for depression was antidepressant medication only, as access to specialty mental health counseling or psychiatric services was not readily available at the participating primary care facilities during the time frame of the trial.

Randomization and Masking We recruited seven primary care facilities housing 10 independent care teams (clusters). Three facilities had two teams each, and four had one team. Although staff and providers from different facilities and teams attend role-specific training together and may share managers, each team has unique support staff, providers, and patient panels. We used a blocked design to limit the possibility of patients crossing over from a team assigned to one randomization group to one in the other group (contamination). Because of a negative association between minority race/ ethnicity and depression diagnosis and treatment receipt, we stratified the teams by the race/ ethnicity of the respective patient populations at each facility (plurality Hispanic, non-Hispanic black, or non-Hispanic white). Prior to randomization, we blocked eight of 10 teams into four pairs within strata because they: (a) shared the same facility (three facilities with two teams each); or (b) were from closely located neighborhoods (two facilities with one team each).

Outcome assessors who obtained written consent, conducted the baseline depression assessment, and collected clinical outcomes were blinded to cluster allocation and were not involved in other study procedures. Patient participants were blinded to group assignment. Participating providers were not blinded.

Protocol Change Prior to recruiting patients into the intention-to-treat (ITT) groups, we changed the primary outcome at the trial registration site on 4/29/10 from the outcome specified in the original 2008 protocol, "adherence to antidepressant medication", to "remission from depression." However, detecting remission, defined as an event where depressive symptoms fall below a clinically significant level for a prolonged period, entails weekly or bi-weekly outcome assessments (Nierenberg, 2001; Rush et al., 2006). Limited study resources precluded closely spaced outcome assessments over 36 weeks. Therefore, to better understand trajectories of clinical outcome for the primary care patients assigned to teams staffed by providers trained to discuss depression with Motivational Interviewing versus those patients assigned to teams staffed by untrained providers, measures of both continuous depressive symptoms and a binary outcome measure (Patient Health Questionnaire-9 (PHQ-9) score < 5) were calculated for each group at 6, 12, and 36 weeks.

Primary Care Providers In May 2009, the research team emailed 53 providers from 13 primary care teams (eligible clusters) in eight facilities with an invitation to participate in a study of "training for a new counseling method for treating depression." Inclusion criteria included working at least 1.5 days per week in outpatient care, previous experience treating depression, and availability for a one-day baseline MI training on 7/25/09. We obtained consent from providers prior to randomization.