Arnold 1989.

Study characteristics
Methods	RCT. Parallel design with 2 arms. Duration: 6 months, intervention to 10 weeks and follow‐up to 6 months for some outcomes. Location: single centre in the USA.
Participants	Inclusion: living at home, planned to receive potentially curative radiotherapy for cancers of head and neck Exclusion: both chemotherapy and radiotherapy planned for treatment Number randomised: 50 adults. Gender split: 29 males and 21 females. Age: 34 ‐ 88 years. Nutritional status: mean weight in treatment and comparison groups was 1 ‐ 2 kg below usual weight at study entry.
Interventions	Intervention: participants (n = 23) received dietary advice and ONS in the form of intensive dietary counselling and the prescription of nutritional supplements to provide an additional 960 ‐ 1080 kcal/day. Control: participants (n = 27) received dietary advice alone in the form of intensive dietary counselling.
Outcomes	Survival*, number having a complete response to therapy, radiation side‐effects, tumour status, body weight*, serum albumin, transferrin, change in dietary energy*, protein intake.
Publication details	Language: English. Funding: not mentioned. Publication status: peer‐reviewed journal.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Described as randomised, but no details of method.
Allocation concealment (selection bias)	Unclear risk	No details of method of allocation concealment.
Blinding (performance bias and detection bias) Clinical outcomes	Low risk	The trial was unblinded. However, this is unlikely to influence clinical outcomes.
Blinding (performance bias and detection bias) Functional outcomes	Unclear risk	No functional outcomes reported.
Blinding (performance bias and detection bias) Nutritional outcomes	High risk	The trial was unblinded. Nutritional outcomes could have been influenced by lack of blinding.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded and likely that researchers and participants were aware of group allocation as this was a nutritional intervention. It is possible that assessment of some outcomes was influenced by lack of blinding
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Judged to be unclear, as low risk for clinical outcomes and high risk for nutritional outcomes.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No withdrawals. 3 (6%) deaths in the dietary counselling and supplement group, no deaths in the control group.
Selective reporting (reporting bias)	High risk	No study protocol identified, thus unable to judge whether all planned outcomes were reported. Data on mortality obtained from the paper. Data on weight change obtained by extrapolation from Figure 3. Energy intake data presented in a figure with no SDs or SEs, therefore risk of bias. No response received from author to request for data.
Other bias	Low risk	Baseline variables stated, groups similar at baseline.