[Summary text]
Study design: Randomized controlled trial
Study grouping: Parallel group
Baseline Characteristics
Intervention
Control
Included criteria: The eligibility and inclusion criteria were a diagnosis of GAD,giving written consent before entry in the study and aged 18 years or older. Patients not willing to withdraw psychotropic medication for a period of 3 weeks before entry to the trial were not included but received treatment outside of the trial.
Excluded criteria: known somatic diseases, psychosis, recent suicidal attempts and/or current intent, primary post-traumatic stress disorder, cluster A or cluster B personality disorder, substance dependence or unwilling-ness to accept random allocation.
Intervention Characteristics
Intervention
Control
Grad af angst, Beck Anxiety Inventory (BAI)
Funktion, Penn State Worry Questionnaire (PSWQ)
Frafald, alle årsager
Bedring, recovered or reliably improved on PSWQ
Sponsorship source: This trial was funded by the Norwegian University of Science and Technology (SAK: PI-4-215-06,SAK: PI-13-114-08)
Country: Norway
Setting: Outpatient clinic
Authors name: Hans M. Nordahl
Institution: Department of Mental Health, Norwegian University of Science and Technology and Research Director, St Olavs Hospital, Nidaros DPS,Norway
Email: Hans.nordahl@nt.nu
Address: Professor Hans M. Nordahl, Department of Mental Health, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, PO Box8905, N-7006 Trondheim, Norway.
Selection bias (biased allocation to interventions) due to inadequate generation of a randomised sequence
Quote: "Trial participants were randomly assigned to one of three conditions, using the IBM random number generator program. Randomisation was stratified by gender and by DSM-IV 22 major depressive disorder,"
Selection bias (biased allocation to interventions) due to inadequate concealment of allocations prior to assignment
Quote: "randomisation sequence was prepared by the trial statistician, who was independent of patient recruitment."
Judgement Comment: Insufficient information on allocation concealment.
Performance bias due to knowledge of the allocated interventions by participants and personnel during the study
Judgement Comment: No information of blinding of participants and personnnels. Blinding not feasible.
Detection bias due to knowledge of the allocated interventions by outcome assessors
Judgement Comment: No information of blinding of outcome assessors. Outcomes were measured with self-reported questionnaires and participants were not blinded.
Attrition bias due to amount, nature or handling of incomplete outcome data
Judgement Comment: Few participants were lost to follow up and losses to follow-up were balanced in the groups and for reasons not related to outcome. ITT analyses performed.
Reporting bias due to selective outcome reporting
Judgement Comment: Registered at ClinicaTrials.gov. Only the two outcomes PSWQ and STAI are stated in the protocol. STAI stated as a primary outcome in the protocol but as a secondary outcome in the report. One or more primary outcomes were not pre-specified in study protocol
Bias due to problems not covered elsewhere in the table
Judgement Comment: There are to publications on this Study. Nordahl. et all and Kvistedal. Kvistedal is a preliminary analysis of the trial. This means that the blinding of the randomization was broken before the inclusion were completed.