Andersson 1987.

Methods	Double‐blinded RCT. States that follow‐up was for 6 months after onset of disease but study start and end dates not reported
Participants	60 adults (aged 15 to 30) hospitalised with symptoms of infectious mononucleosis for 1 week or less. 2 participants excluded because of a change in diagnosis and two excluded for not complying with medication. Of included patients at enrolment, 34 were male and 23 female
Interventions	Acyclovir 800 mg 5 times daily PO for 7 days versus placebo
Outcomes	Duration of: recovery as assessed by patient and physician, weight loss, fever > 37.5°C, difficulty swallowing, sore throat, tonsillar swelling, tiredness, abdominal pain, liver enlargement, elevated liver enzymes, spleen enlargement, absence from school/work, atypical monocytes > 5%, absolute lymphocytosis > 50%. Number of patients with increased serum creatinine during treatment, number of patients with positive monosticon test after six months. Virological outcomes also measured
Notes	Three patients in the acyclovir group required IV acyclovir and prednisolone for 10 days, whereas none of the placebo group had this treatment Virological findings were only provided for 36/56 patients
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computerised randomisation code
Allocation concealment (selection bias)	Low risk	Drawn from sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	"double‐blind trial" but does not elaborate further. 3 of the participants had IV acyclovir also had steroids so presume blinding was broken here
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	"double‐blind trial" but does not elaborate further
Incomplete outcome data (attrition bias) All outcomes	High risk	2 of the 60 patients were excluded after randomisation because of a change in the diagnosis, and 2 for not following the medication. Results from these patients were not included in analysis
Selective reporting (reporting bias)	High risk	Lymphadenopathy not reported although says in methods that it was measured at visits Virological data only reported for 36 out of 56 patients
Other bias	High risk	Differences in severity of illness 3 patients who had IV acyclovir and steroids included in analysis. Supported by the Wellcome foundation