Pollack 2007a.
| Methods | Study design: Randomised controlled trial | |
| Participants |
Diagnosis: DSM‐IV panic disorder with or without agoraphobia Method of diagnosis: Mini‐International Neuropsychiatric Interview Age: for venlafaxine 75 mg, M = 35.8, SD = 9.97; for venlafaxine 225 mg, M = 37.1, SD = 11.8, for paroxetine M = 37.5, SD = 11 Sex: for venlafaxine 75 mg, females = 65%, males = 35%; for venlafaxine 225 mg, females = 68%, males = 33%; for paroxetine females = 68%, males = 32% Location: Argentina, Mexico, Chile, Costa Rica; setting: outpatients Co‐morbidities: patients with other predominant Axis I or II disorders and important medical conditions were excluded Rescue medication: zaleplon or zolpidem permitted up to 3 times per week for the first 2 weeks of randomised treatment |
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| Interventions |
Participants were randomly assigned to either: (1) venlafaxine 75 mg arm (n = 163) Duration: 12 weeks Treatment Protocol: fixed dosage = 75 mg/day (2) venlafaxine 225 mg arm (n = 167) Duration: 12 weeks Treatment Protocol: fixed dosage = 225 mg/day (3) paroxetine arm (n = 161) Duration: 12 weeks Treatment Protocol: fixed dosage = 40 mg/day (4) placebo arm (n = 162) Duration: 12 weeks |
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| Outcomes |
Time points for assessment: baseline, weeks 1, 2, 3, 4, 6, 8, 10, 12 Outcomes: 1. patients free of panic attacks at endpoint 2. Panic Disorder Severity Scale (PDSS) 3. panic attacks frequency 4. Clinical Global Impression Improvement Score (CGI‐I) |
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| Notes |
Date of study: not stated Funding source: Wyeth Research, Collegeville, Pennsylvania Declarations of interest among the primary researchers: members of advisory boards, and research support received by many pharmaceutical companies, including AstraZeneca, GlaxoSmithKline, Eli Lilly, Pfizer, Roche, Wyeth |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Quote: "randomized". |
| Allocation concealment (selection bias) | Unclear risk | No information provided. |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | Quote: "...they were randomly assigned to receive venlafaxine 75 mg/day, venlafaxine 225 mg/day, paroxetine or placebo once daily in identically appearing capsules". |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | Quote: "...they were randomly assigned to receive venlafaxine 75 mg/day, venlafaxine 225 mg/day, paroxetine or placebo once daily in identically appearing capsules". |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Quote: "statystical analysis on the primary and secondary outcome measures were performed for an ITT population of patients who had at least one post randomisation visit on therapy using LOCF values". |
| Selective reporting (reporting bias) | Unclear risk | Continuous data at endpoint are reported only in graphs. |
| Other bias | High risk | Sponsored by Wyeth; the role of the funder in planning, conducting and writing the study is not discussed. |