Den Boer 1990.

Methods	Study design: Randomised controlled trial
Participants	Diagnosis: DSM‐III‐R Method of diagnosis: not stated Age: for fluvoxamine M = 37, for ritanserin M = 35, for placebo M = 37 Sex: the female to male ratio was almost 3 to 1 in all groups Location: the Netherlands; setting: outpatients Co‐morbidities: patients with a primary diagnosis other than panic disorder were excluded Rescue medication: none
Interventions	Participants were randomly assigned to either: (1) fluvoxamine arm Duration: 8 weeks Treatment Protocol: fixed dosage = 150 mg (2) ritanserin arm Duration: 8 weeks Treatment Protocol: fixed dosage = 20 mg (3) placebo arm Duration: 8 weeks Total number of randomised patients = 60. The number of patients randomised for each arm is not provided.
Outcomes	Time points for assessment: baseline, weekly Outcomes: 1. SCL‐90 2. Hamilton Rating Scale for Anxiety (HAMA) 3. State‐Trait Anxiety Inventory (STAI) 4. Fear Questionnaire (FQ) 5. panic inventory
Notes	Date of study: not stated Funding source: not stated Declarations of interest among the primary researchers: not stated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomised".
Allocation concealment (selection bias)	Unclear risk	No information provided.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "double blind". No further information provided.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Quote: "double blind". No further information provided.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information provided about management of incomplete outcome data.
Selective reporting (reporting bias)	High risk	Data are reported in graphs (HAMA, FQ); other data only partially reported.
Other bias	Unclear risk	Sponsorship bias cannot be ruled out.