Côté 2016.

Study characteristics
Methods	Purpose of the study: improving quality of life, especially pain, appetite and nausea, of people treated by radiotherapy or radiochemotherapy for head and neck squamous cell carcinomas Study setting: 1 university centre in Canada Study period: May 2005 to August 2007 Study design: double‐blind, randomised, placebo‐controlled, parallel‐group design Study duration: 8 weeks (no data on washout period reported); 4 weeks' double‐blind individually titrated dose, 4 weeks' follow‐up
Participants	Type of cancer: head and neck squamous cell carcinoma Inclusion criteria: histological diagnosis of squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, larynx, or a combination of these; treated by radiotherapy alone, postoperative radiotherapy, radiochemotherapy alone, or postoperative radiochemotherapy; aged 18–80 years; no other cancer diagnosis in past 5 years, except for basal cell and squamous cell carcinoma of the skin Exclusion criteria: metastatic disease; history of radiotherapy in the head and neck region; Karnofsky score < 60; cognitive impairment; hepatic insufficiency; pregnant or breastfeeding woman; history of hypersensitivity or adverse reactions to marijuana or other CBs; history of schizophrenia or any other form of psychosis Nabilone: 28 participants; 93% men; mean age 63.5 years; race: not reported; type of cancer pain: not reported; previous cannabis use: not reported Placebo: 28 participants; 71% mean; mean age 63.8 years; race: not reported; type of cancer pain: not reported; previous cannabis use: not reported
Interventions	Nabilone, PO, flexible dosage up to 2 mg/day: administration began the day before the first radiotherapy treatment, with 1 tablet (0.5 mg PO at bedtime). The same dose was maintained for the entire first week (0.5 mg). For the second week, the dose was increased to 2 tablets a day (0.5 mg PO twice daily). From the third week until the end of radiotherapy treatments, the dose was adjusted by the radio‐oncologist to a maximum of 4 tablets a day. Placebo Rescue medication: not reported Allowed cotherapies: antiemetics (metoclopramide only) and analgesics (only paracetamol/codeine, hydromorphone or transdermal fentanyl) allowed. Dosages not reported
Outcomes	Proportion of participants reporting no worse than mild pain on treatment at 14 days after start of treatment (typically < 30/100 mm on a 100‐mm VAS or < 3 on an 11‐point NRS): not assessed Participant impression to be much or very much improved: not assessed Withdrawal due to adverse events: no details of assessment reported Combined responder: not assessed Pain relief ≥ 30%: VAS 0–10, time frame not reported. Imputation method could not be used because baseline values were not reported. Pain relief ≥ 50%: VAS 0–10, time frame not reported. Imputation method could not be used because baseline values were not reported. Mean pain intensity: VAS 0–10, time frame not reported. No means and SDs reported. Sleep problems: EORTC QLQ‐C30 subscale sleep. No means and SDs reported. Depression: EORTC QLQ‐C30 subscale mood. No means and SDs reported. Anxiety: not assessed Daily maintenance opioid therapy dose: not assessed Daily breakthrough opioid therapy dose: not assessed Withdrawals due to lack of efficacy: not reported in detail Nervous system disorders adverse effects: no details of assessment reported Psychiatric disorders adverse effects: no details of assessment reported Any serious adverse event: no details of assessment reported
Notes	Funding: research grants from the Canadian Institutes of Health Research and the Fonds de Recherche en Santé du Québec. ICN Valeant Pharmaceuticals provided the nabilone and the placebo tablets during the trial. Conflicts of interest: authors declared no conflicts of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No details reported.
Allocation concealment (selection bias)	Unclear risk	Quote: "The physicians, nurse, and subjects were blinded: the hospital pharmacist was the only one who knew patients' grouping." Comment: no details of blinding reported.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Nabilone and placebo "both look identical."
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details reported.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No details reported if ITT was applied.
Selective reporting (reporting bias)	Unclear risk	No study protocol available.
Selection bias	Low risk	No differences in demographic and clinical parameters between the study groups at baseline.