Macia 1991c.

Study characteristics
Methods	RCT. Parallel design with 2 treatment arms. Duration: not reported. Location: Spain.
Participants	Inclusion criteria: adults receiving radiotherapy for cancers of head and neck, breast and abdominopelvic area. Exclusion criteria: Karnofsky score < 50, previous diet therapy for diabetes, hypercholesterolemia or other conditions. Number randomised: 92 participants (intervention group, n = 30; control group, n = 62). Numbers of withdrawals and deaths not reported. Gender split: not reported. Age: not reported. Nutritional status: unclear.
Interventions	Intervention: participants received dietary advice in the form of dietary instructions on appropriate alimentation during radiotherapy given verbally and in writing. Control: participants received no dietary advice in the form of ad lib food intake and no dietary instruction.
Outcomes	Weight*, TSF*, MAUC*, MAMC*, BMI*, total protein, albumin, transferrin, total lymphocyte count, iron, cholesterol, triglycerides, clinical observations.
Publication details	Language: English. Funding: none declared. Publication status: peer‐reviewed journal.
Notes	Dietary advice given by doctors from nutrition and dietetic unit. The ID Macia 1991c has been used to identify the abdominopelvic cancer group.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Used coin toss to randomise participants.
Allocation concealment (selection bias)	Unclear risk	No details provided however unlikely that lack of concealment would influence group allocation.
Blinding (performance bias and detection bias) Clinical outcomes	Low risk	Paper states that clinical variables were assessed by doctors unaware of group allocation.
Blinding (performance bias and detection bias) Functional outcomes	Unclear risk	No functional outcomes assessed.
Blinding (performance bias and detection bias) Nutritional outcomes	High risk	Not stated and likely that lack of blinding would influence the assessment of some nutritional outcomes.
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	Not described for all outcomes and absence of blinding of some outcomes might influence the results.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Numbers of withdrawals and deaths not reported.
Selective reporting (reporting bias)	Unclear risk	No protocol identified. All outcomes in the methods reported but as mean change at baseline and end of follow‐up according to site of tumour therefore change scores were calculated and SDs imputed. No response received from author to requests for data.
Other bias	Unclear risk	Baseline variables not reported, not sure if groups similar at baseline.