Katon 2001.

Methods	Patients were randomized to the relapse prevention intervention versus usual care in blocks of 8. Within each block, the randomization sequence was computer‐generated. The telephone survey team conducting the follow‐up assessments (at 3, 6, 9, and 12 months) were blinded to randomization status. Patients could not be blinded due to the nature of the intervention (i.e. patient education, visits with depression specialist, telephone monitoring and follow‐up). The primary care physicians were also not blinded
Participants	Patients between the ages of 18 and 80 years who received a new antidepressant prescription (no prior prescriptions within the previous 120 days) from a primary care physician for the diagnosis of depression or anxiety were eligible for the study. Inclusion criteria for the relapse prevention study obtained during the baseline interview included patients with fewer than 4 DSM‐IV major depressive symptoms and a history or 3 or more episodes of major depression or dysthymia or 4 residual depressive symptoms but with a mean Symptom Checklist 20 (SCL‐20) depression score of less than 1.0 and a history a major depression/dysthymia. Exclusion criteria included having a screening score of 2 or more on the CAGE alcohol screening questionnaire, pregnancy or currently nursing, planning to disenroll from the Group Health Cooperative of Puget Sound (GHC) within the next 12 months, currently seeing a psychiatrist, limited command of English, or recently using lithium or antipsychotic medication
Interventions	The intervention included patient education, 2 visits with a depression specialist, and telephone monitoring and follow‐up. Before the first study visit, the intervention patients were provided a book and videotape developed by the study team that was aimed at increasing patient education and enhancing self treatment of their depression. They were also scheduled for 2 visits with a depression specialist (one 90‐minute initial session and one 60‐minute follow‐up session) in the primary care clinic. 3 addition telephone visits at 1, 4, and 8.5 months from session 2 with the depression specialist and 4 personalized mailings (2, 6, 10, and 12 months) were scheduled over the following year. The mailed personalized feedback contained a graph of patients' Beck Depression scores over the course of the intervention program and checklists for patients to send back to the depression specialist, including early warning signs of depression and whether they were still adhering to their medication plan. The depression specialist reviewed monthly automated pharmacy data on antidepressant refills and alerted the primary care physician and telephoned the patients when mailed feedback or automated data indicated they were symptomatic and/or had discontinued medication. The ultimate aim of the intervention was to have each patient complete and follow a 2‐page written personal relapse prevention plan, which was also shared with his/her primary care provider. Follow‐up telephone calls and mailings were geared toward monitoring progress and adherence to each patient's plan. Usual care for most patients was provided by the GHC family physicians in the 4 primary care clinics and involved prescription of an antidepressant medication, 2 to 4 visits over the first 6 months of treatment, and an option to refer to GHC mental health services. Both intervention and control patients could also self refer to a GHC mental health provider
Outcomes	Measurement of compliance: patients' adherence to antidepressant medication was measured at 3, 6, 9, and 12 months after randomization by a telephone interviewer. Based on computerized automated data from prescription refills, patients were rated as adherent at the 3‐, 6‐, 9‐, and 12‐month follow‐up periods as well as whether they received adequate dosage of antidepressant medication for 90 days or more during the 1‐year period. The lowest dosages in the ranges recommended in the Agency for Healthcare Policy and Research guidelines developed for newer agents were used to define a minimum dosage standard. Measurement of clinical health outcomes: baseline and follow‐up interviews assessing depressive symptoms (at 3‐, 6‐, 9‐, and 12‐months) included the SCL‐20 depression items (scored on a 0 to 4 scale), the dysthymia and current depression modules of the SCID, the NEO Personality Inventory Neuroticism Scale and the Longitudinal Interval Follow‐up Evaluation to measure incidence and duration of episodes within each 3‐month block of time
Notes	―
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Patients were randomized to the relapse prevention intervention (I) versus usual care (UC) in blocks of 8. Within each block, the randomization sequence was computer‐generated(pg 242)
Allocation concealment (selection bias)	Unclear risk	Allocation concealment is not described; we only know that it followed the baseline interview to assess eligibility, and that a substantial proportion refused randomization at that point (pg 242). Of the 480 patients completing baseline interviews for the relapse study, 386 patients (80.4%) were successfully randomized to the relapse prevention study; 69 patients (14.4%) accepted randomization to a separate persistence study based on having 4 DSM‐IV symptoms and an SCL‐20 depression score greater than 1.0; and 25 (5.2%) refused randomization
Selective reporting (reporting bias)	High risk	Longitudinal interval follow‐up evaluation was only reported at baseline and not as outcome
Other bias	Unclear risk	Selection bias is not excluded(pg 242). Baseline interviews were completed with 480 patients (68.4%). Patients refusing baseline interviews or who were ineligible for participation in the trial did not differ on age, sex, medical comorbidity, number of current depressive symptoms on the SCID, or prior mental health utilization compared with those successfully randomized. Some bias noted in 'Limitations' but unclear if these substantially effect results. (pg 246) "Limitations of this research included the sample studied and our ability to accurately adjust our findings for missing data. We relied on imputation models that assumed that we could reasonably predict non‐response using baseline data. Although these assumptions are untestable, we believe they are reasonable and that our results offer a more realistic estimate of intervention effects than analyses that completely ignore missing data."
Blinding of outcome assessment (detection bias) Adherence measure	Low risk	(PRIMARY) SELF REPORT ‐ INTERVIEW ‐ (pg 243) "...by a telephone interviewer blinded to the patients' randomization status"
Blinding of outcome assessment (detection bias) Patient outcome	Low risk	(PRIMARY) SCL‐20 ‐ (pg 243) "...by a telephone interviewer blinded to the patients' randomization status."
Blinding of participants (performance bias) Adherence measure	High risk	(PRIMARY) SELF REPORT ‐ INTERVIEW ‐ No mention of blinding of patients; subjective measure
Blinding of participants (performance bias) Patient outcome	High risk	(PRIMARY) SCL‐20 ‐ No blinding, and this could have affected the outcome
Blinding of personnel (performance bias) Adherence measure	Unclear risk	(PRIMARY) SELF REPORT ‐ INTERVIEW ‐ No information is provided on how adherence is actually measured by phone, and the outcome is not further reported
Blinding of personnel (performance bias) Patient outcome	Unclear risk	(PRIMARY) SCL‐20 ‐ No mention of blinding of study staff
Incomplete outcome data (attrition bias) Adherence measure	Unclear risk	(PRIMARY) SELF REPORT ‐ INTERVIEW ‐ No information is provided on how adherence is actually measured by phone, and the outcome is not further reported. Unclear how missing data impacts results
Incomplete outcome data (attrition bias) Patient outcome	Unclear risk	(PRIMARY) SCL‐20 ‐ Dropouts are likely to be linked to the severity of the outcome (depression) but unclear how missing data impacts results