Jochimsen 1978.

Study characteristics
Methods	Purpose of the study: to assess the analgesic activity of a synthetic THC analogue at 2–4 mg 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 hours before the intake of the medication
Participants	Type of cancer: no details reported Inclusion criteria: pain related to malignancies and history of frequent analgesic use, though 1 had received large doses of narcotics Exclusion criteria: conditions interfering with drug metabolism, severe organic disease other than cancer, pregnancy or major psychiatric disorders Synthetic THC analogue: 35 participants; 17% men; aged 38–77 years; race: not reported; type of cancer pain: not reported; pain medication: not reported; previous cannabis use: not reported
Interventions	Synthetic nitrogen‐containing benzopyran derivative (modification of delta‐I‐trans‐THC): 2 mg and 4 mg single, fixed dosage PO Codeine: 60 mg and 120 mg single, fixed dosage PO Placebo: 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. Number of participants with moderate pain relief reported Pain relief ≥ 50%: reported Mean pain intensity: hourly ratings of the severity of pain (0, absent; 1, mild; 2, moderate; 3, severe) were used to determine hourly pain reduction scores 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: at hourly intervals, the participant completed an 11‐item subjective effects questionnaire, designed to quantify certain psychic manifestations of the test preparations. Data provided not suited for analysis. Psychiatric disorders adverse effects: at hourly intervals, the participant completed an 11‐item subjective effects questionnaire, designed to quantify certain psychic manifestations of the test preparations. Data provided not suited for analysis. Any serious adverse event: not assessed
Notes	Funding: grant RR‐59 from the General Clinical Research Canters Program Division of Research Resources, National Institutes of Health and Abbott Laboratories. 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	Low risk	Quote: "Identical appearing capsules."
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	Responder analysis.
Selective reporting (reporting bias)	Unclear risk	No prepublished study protocol available.
Selection bias	Low risk	Identical baseline parameters of the study groups due to cross‐over design.