Coodley 1993 USA.

Methods	Country: USA Setting: hospital outpatient clinics Duration of recruitment: not stated Duration of follow‐up: 8 weeks Design: randomized cross‐over trial; no washout period
Participants	Inclusion criteria: HIV‐seropositive Exclusion criteria: on other forms of vitamin A supplementation; significant hepatic or renal dysfunction; active opportunistic infection or fever Participants randomized: 21 20 male and 1 female Median age: not stated Loss to follow‐up/withdrawal: 4 Exclusions postrandomization: 0
Interventions	Intervention: 60 mg beta‐carotene Control: placebo Duration: 3 times daily for 4 weeks
Outcomes	Primary outcomes CD4 counts Secondary outcomes White blood cell count Lymphocyte count B‐lymphocytes Serum beta‐carotene
Adverse events	No toxicity; skin discolouration in treatment group
Notes	CD4 count data reported as means and ranges 16 participants received ART. Source of funding: Hoffman La Roche Inc.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The trial authors did not describe the method of random sequence generation.
Allocation concealment (selection bias)	Unclear risk	The trial authors did not describe the method of allocation concealment.
Blinding (performance bias and detection bias) All outcomes	Low risk	Participants and investigators were blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Low attrition at 1 month; the trial authors provided reasons.
Selective reporting (reporting bias)	Unclear risk	There was insufficient information; the trial protocol was unavailable.
Other bias	Unclear risk	The trial authors did not declare on conflict of interest, if any.