Noyes 1975b.

Study characteristics
Methods	Purpose of the study: reducing moderate‐to‐severe cancer pain Study setting: 1 university hospital in USA Study period: not reported Study design: double‐blind, randomised, placebo‐controlled, cross‐over design Study duration: 1 day each. Regular medication was stopped 4.5 hours before the intake of the medication
Participants	Type of cancer: 5 breast, 2 malignant lymphoma, 1 cervix, 1 colon and 1 lymphoepithelioma Inclusion criteria: continuous pain of moderate severity Exclusion criteria: participants receiving large doses of narcotics Synthetic THC analogue: 10 participants; 20% men; mean age 51 years; race not reported; type of cancer pain: not reported; pain medication: (quote) "None were receiving large doses of narcotics." 7 participants had received methadone as part of their regular analgesic regimen. Previous cannabis use: not reported
Interventions	Synthetic THC analogue, fixed dosage: 5 mg, 10 mg, 15 mg and 20 mg single dosage PO Placebo: single dose, PO Rescue medication: none Allowed cotherapies: no details 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 Patient 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%: not reported; imputation method not applicable because baseline pain scores not reported Pain relief ≥ 50%: not reported; imputation method not applicable because baseline pain scores not reported. Number of participants with substantial pain relief reported Mean pain intensity: hourly ratings of the severity of pain (0, absent; 1, mild; 2, moderate and 3, severe) were used to arrive at hourly pain reduction scores. The sum of hourly pain reduction or relief scores for a given 7‐hour observation period (total reduction or relief scores) was used as a basis for statistical analysis. Sleep problems: not assessed Depression: not assessed 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 Nervous system disorders adverse effects: the nurse's observations, including evident or reported adverse effects, were recorded on a pain chart designed for that purpose. The same observer also administered an 11‐item subjective effects questionnaire hourly and an adverse effects inventory at the end of each 7‐hour observation period. Psychiatric disorders adverse effects: the nurse's observations, including evident or reported adverse effects, were recorded on a pain chart designed for that purpose. The same observer also administered an 11‐item subjective effects questionnaire hourly and an adverse effects inventory at the end of each 7‐hour observation period. Any serious adverse event: not reported
Notes	Funding: grant RR‐59 from the General Clinical Research Canters Program Division of Research Resources. National Institutes of Health Conflicts of interest: not declared
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	No details reported.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No details reported.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	Completer analysis.
Selective reporting (reporting bias)	Unclear risk	No prepublished protocol available.
Selection bias	Low risk	Identical baseline data of the study groups due to cross‐over design.