Table 2.

Detailed characteristics of included studies

Study ID	Year	Journal	Pubmed ID	Trial registry ID
Abrams 2007	2007	Neurology	17296917	NCT00046722
Population	55 HIV + adults with symptomatic HIV-DSPN and at least 30/100 VAS, on stable pain regimen for 8 weeks prior to enrolment, with prior experience of smoking cannabis randomized in 2 groups of size: 27/28. Our Bayesian analysis is based on 50 participants with one observation per patient, as provided by the primary study authors. Age (Experimental, Control): 50 years (SD ±6)), 47 (SD ± 7) Gender (male/female/other): Experimental 22/5/0 Control 26/2/0
Intervention	Experimental: Patient smoked one cigarette three times per day as tolerated Pre-rolled, whole herb Cannabis cigarettes were provided by NIDA and contained 3.56% delta-9-THC. Control: identical pre-rolled cigarettes with the active ingredient extracted. Dose estimate: 32 mg THC per session; 96 mg THC per day
Primary Outcome	Daily pain diary recording the VAS at 8am for average pain during the previous 24 hours.
Study Methods	Randomized, double-blind (patient, outcome assessor), parallel design, placebo controlled, single center (university) clinical trial in San Francisco, California, USA starting in 2003
Notes	Also published as an abstract at the 2nd Annual meeting of the International Association for Cannabis as Medicine, 2005 Secondary outcomes: Acute analgesic effects: Long thermal stimulation Anti-hyperalgesic effects: Heat-capsaicin model, Profile of Mood States
Study ID	Year	Journal	Pubmed ID	Trial registry ID
Ellis 2009	2008	Neuropsychopharmacology	18688212	NCT00255580
Population	34 HIV + adults with symptomatic HIV-DSPN and pain score >5/20 on DDS (Discriptor Differential Scale), most participants were previously exposed to potentially neurotoxic deoxy-nucleoside reverse transcriptase inhibitors; 16 started control/experimental, 18 started experimental/control. 28 participants with a total of 56 observed responses were included in the Bayesian analysis. Age (all) 49.1 years (SD ±6.9)), Gender (male/female/other): 33/1/0
Intervention	Experimental: Patient smoked cannabis, titrating dose up or down to effective pain control/ tolerable adverse effects, starting at 4 percent to range between 1 to 8 percent delta-9-tetrahydrocannabinol (THC) concentration by weight. Pre-rolled, whole herb Cannabis cigarettes were provided by the National Institute on Drug Abuse. Control: identical pre-rolled cigarettes with the active ingredient extracted. Dose estimate: average 96 mg THC per day
Primary Outcome	Crossover difference in change of DDS (Descriptor Differential Scale 0-20 scale “a ratio scale containing 24 words describing pain intensity and unpleasantness.”) comparing baseline to after treatment
Study Methods	Randomized, double-blind (patient, outcome assessor), cross-over design, placebo controlled, single center (university) clinical trial at the University of California, San Diego in 2006
Notes	Secondary outcomes: McGill Questionaire, VAS, SIP (Sickness Impact Profile), BSI (Brief Symptom Inventory), UKU side effect rating, Highness/Sedation Scale, HIV load
Study ID	Year	Journal	Pubmed ID	Trial registry ID
Ware 2010	2010	Canadian Medical Association Journal	20805210	ISRCTN68314063
Population	23 adults with non HIV neuropathy pain of at least 3 months duration caused by trauma or surgery defined by pain intensity score greater than 40/100 VAS, on a stable analgesic regimen, not having smoked cannabis in the preceding year. 23 participants with a total of 86 observed responses were included in the Bayesian analysis. Age (all): 45.4 years (SD ±12.3) Gender (male/female/other): 11/12/0
Intervention	Experimental: NIDA and Prairie plant systems prepared three different potencies of THC (2.5%, 6%, 9.4%) from whole herb in gelatine capsules inhaled through pipe. Control: Ethanolic extraction was used to prepare the placebo. Dose estimate: 0, 1.625, 3.9 and 5.85 mg/day (average) THC per period
Primary Outcome	Average Daily Pain Intensity on the 11-item numeric rating scale (NRS) average over five treatment days (least pain value, average pain value and worst pain value) during four consecutive crossover periods of 14 days each (five treatment days and 9 washout days afterwards)
Study Methods	Randomized, double-blind (patient, outcome assessor), 4 period crossover Latin square design, placebo controlled, single center (university) clinical trial in McGill University, Montreal, Canada, starting in 2003
Notes	The linear model did not consider inter participant effect. Secondary outcomes: Pain Quality: McGill Questionaire, Sleep (Leeds Sleep Evaluation Questionaire), Mood Effects: short-form Profile of Mood States, Quality of Life: EQ-5D health outcomes
Study ID	Year	Journal	Pubmed ID	Trial registry ID
Wilsey 2008	2008	The Journal of Pain	18403272	NCT00254761
Population	38 adults with non HIV neuropathy (complex regional pain syndrome (CRPS type I), spinal cord injury, peripheral neuropathy, or nerve injury) with prior cannabis experience and a VAS > 30/100. 38 participants with 102 observed responses were included in the Bayesian analysis. Age (all): 46 years (range 21-71) Gender (male/female/other): 20/18/0
Intervention	Experimental Participants inhaled a total of 9 standardized cued-puff. Cannabis was harvested from whole plant and rolled into cigarettes at the U of Mississippi under supervision of NIDA ranging in strength from 0%, 3.5% to 7%. Control: Placebo Cigarettes were made from whole plant with extraction of Cannabis. Dose estimate: 0 Placebo, 19.25 (low dose, range 7-30.45), 34.3 (high dose, range 18.9-60.9) mg THC/day (Session)
Primary Outcome	VAS measuring spontaneous pain relief; time effects were studied with a linear model.
Study Methods	Randomized, double-blind (patient, outcome assessor), parallel design, placebo controlled, single center (university) clinical trial at UC Davis Medical Center Sacramento, California started in November 2003
Notes	Secondary outcomes: pain unpleasantness (VAS), heat pain threshold, Neuropathic Pain Scale, Neurocognitive assessment and plasma Cannabis concentration
Study ID	Year	Journal	Pubmed ID	Trial registry ID
Wilsey 2013	2013	The Journal of Pain	23237736	NCT01037088
Population	39 adults with non HIV neuropathy due to reflex sympathetic dystrophy, peripheral neuropathy, post-herpetic neuralgia, post-stroke pain, multiple sclerosis or spinal cord injury with previous cannabis exposure (16 current, 23 ex-users) and a VAS pain intensity greater than 30/100. 39 participants with 111 observed responses were included in the Bayesian analysis. Age (all): 50 years (SD ±11)) Gender (male/female/other): 28/11/0
Intervention	Experimental: Participants used a volcano vaporizer under the flexible-dose design of Wilsey 2008. The minimum and maximum cumulative doses for each visit were 8 and 12 puffs. Cannabis was harvested at the University of Mississippi under the supervision of NIDA. Control: Placebo was made from whole plant with removal of cannabinoids. Dose estimate: Maximum of 0, 10.32, 28 mg THC/day (Session), presuming they were administered the entire 800 mg dose.
Primary Outcome	VAS before and after consuming vaporized cannabis.
Study Methods	Randomized, double-blind (patient, outcome assessor), crossover design, placebo controlled, single center (university) clinical trial at the University of California, Davis, started December 2009
Notes	Secondary outcomes: Patient Global Impression of Change (PGIC); Neuropathic Pain Scale (NPS); WAIS-III, Hopkins Verbal Learning Test (revised), Grooved Pegboard Test

We provide detailed characteristics of the five included randomized controlled clinical trials investigating smoked or inhaled cannabis for painful neuropathy. Two trials recruited patients with HIV related Distal Sensory Polyneuropathy (HIV DSPN), three included participants with neuropathies of other etiologies. (VAS Visual Analogue Scale; SD Standard deviation; NA not available; NIDA US National Institute of Drug Abuse)