Berk 1999.

Methods	Study design: double‐blind, parallel, randomised controlled study
Participants	Diagnosis: bipolar disorder, manic phase Method of diagnosis: DSM‐IV criteria. Participants were interviewed using the structured clinical interview, MINI Age: for lithium, median = 31.9 years (SD =not provided); for olanzapine, median = 29.4 years (SD =not provided); range = 20‐59 years Sex: lithium 7 women; 8 men, olanzapine 6 women; 9 men, lamotrigine ‐ data not provided. Location: not described Co‐morbidities: not described Adjunctive therapy: none Adjunctive medication: lorazepam (4–12 mg daily) was available for the treatment of restlessness or disruptive behaviour. No other psychotropic medication was permitted during the course of the study. Anticholinergic medication (biperiden 2‐6 mg daily) was allowed for acute dystonia, and severe parkinsonian symptoms.
Interventions	Participants were randomly assigned to either: Experimental arm ‐ lithium N = 15 Duration: 4 weeks Treatment protocol: lithium was maintained at a constant dose of 400 mg twice daily, resulting in a mean serum concentration of 0.743 mmol/L. Therapist/face‐to‐face contact: not described Comparator arm 1 ‐ lamotrigine N = 15 Duration: 4 weeks Treatment protocol: dosing schedule for lamotrigine was 25 mg daily during week 1, 50 mg daily during week 2 and 100 mg daily during weeks 3 and 4. This was a more rapid titration schedule than recommended to minimise the risk of skin rash, but was necessary due to the short treatment period. Therapist/face‐to‐face contact: not described Comparator arm 2 ‐ olanzapine N = 15 Duration: 4 weeks Treatment protocol: dose of olanzapine was 10 mg daily. Trial medication was administered as a twice daily dose, with a morning placebo in the olanzapine group Therapist/face‐to‐face contact: not described
Outcomes	Timepoints for assessment: baseline and weekly Primary outcome: MRS Secondary outcome: Discontinuation BPRS Score CGI ‐ severity scale CGI score CGI – improvement scale GAF Scale MAS scale SAS scale Adjunctive medication used Barnes akathisia scale
Notes	Date of study: unknown Funding source: Eli Lilly South Africa for the supply of sample olanzapine Declarations of interest among the primary researchers: not described
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Randomised" ‐ only description
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding (performance bias and detection bias) All outcomes	Low risk	Double‐blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not described
Selective reporting (reporting bias)	High risk	Poorly reported
Other bias	Unclear risk	None identified