Lawrence 1993.

Methods	6‐week cross‐over study planned. However, significant carry‐over effect of treatment noted at end of study, therefore analysis restricted to the first 6‐week treatment period.
Participants	19 adolescents and adults diagnosed with CF on genotype, sweat test, or clinically (median age 17 years, age range 12 years to 26 years), 11 male, 5 female. 3 participants excluded due to requiring a course of corticosteroids for asthma attacks. All were recruited within 4 weeks of hospitalisation for acute respiratory infection and judged to be in optimum condition for disease stage. All were Pseudomonas aeruginosa colonised and produced at least 5 ml sputum daily. Initial randomisation gave groups with comparable baseline characteristics except for age. The treatment group also had significantly greater weight, peripheral blood leucocyte and neutrophil counts.
Interventions	2.7 g EPA daily compared with identical olive oil placebo capsules, over 6 weeks.
Outcomes	Outcomes included in this review: number of people experiencing adverse events; number of deaths; changes in haematological and growth indices; changes in lung function; changes in in‐vitro neutrophil chemotaxis.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Did not state the randomisation technique.
Allocation concealment (selection bias)	Unclear risk	No details were provided in the primary paper.
Blinding (performance bias and detection bias) All outcomes	Low risk	Described as double blind, treatment was administered as 'identical olive oil capsules'.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Of the 19 participants recruited, 3 participants were excluded from the study before analysis due to corticosteroid treatment during the first treatment period.
Selective reporting (reporting bias)	Unclear risk	Protocol not available for comparison, so unable to definitely eliminate selective reporting.
Other bias	Low risk	No additional bias identified.