Table 1A.
Characteristics of included reviews of gabapentin (n = 70)
| Review Characteristic | n | (%) |
|---|---|---|
| Year published | ||
| 2001–2005 | 4 | (6%) |
| 2006–2010 | 11 | (16%) |
| 2011–2015 | 19 | (27%) |
| 2016–2020 | 36 | (51%) |
| Review condition(s)/indication(s) i | ||
| Neuropathic pain (e.g., phantom limb-pain, neuropathic cancer-pain) | 18 | (25%) |
| Post-operative pain | 18 | (25%) |
| Epilepsy (e.g., essential tremor, seizure disorders) | 12 | (17%) |
| Postherpetic neuralgia | 7 | (10%) |
| Fibromyalgia | 6 | (9%) |
| Migraine headaches | 5 | (7%) |
| Vasomotor symptoms (i.e., hot flashes) | 4 | (6%) |
| Alcohol dependence | 3 | (4%) |
| Psychiatric disorders (bipolar disorder, attention deficit disorder, obsessive compulsive disorder, post-traumatic stress disorder) | 1 | (1%) |
| Restless leg syndrome | 1 | (1%) |
| Non-specific–review focused on specific drugs | 7 | (10%) |
| Gabapentin assessed as … | ||
| Single intervention (with one or more doses) | 61 | (87%) |
| Multiple interventions (separated by dose) | 9 | (13%) |
| Comparators evaluated against gabapentin ii | ||
| Direct comparisons against gabapentin (n = 106) | 60 | (86%) |
| Placebo | 52 | |
| Antiepileptic drugs | 11 | |
| Tricyclic antidepressants | 8 | |
| Pregabalin | 4 | |
| NSAIDs | 4 | |
| SNRIs or SSRIs | 3 | |
| Benzodiazepines | 2 | |
| Opioids | 3 | |
| Other (cannabinoids, topical capsaicin/lidocaine, vitamin E, estrogen, isoflavones, tibolone, hypnotic induction, electroacupuncture, etc.) | 17 | |
| Network Meta-Analysis (all interventions compared with each other) | 11 | (16%) |
| Specific guidance followed for general review methods/reporting iii | ||
| PRISMA | 26 | (37%) |
| Cochrane | 23 | (33%) |
| AHRQ | 2 | (3%) |
| FDA | 0 | (0%) |
| IOM | 0 | (0%) |
| Other (e.g., BMJ Clinical Evidence, NHS R&D HTA, ISPOR, PROSPECT) | 9 | (13%) |
| Source of funding or material support iv | ||
| Government (e.g., National Institutes of Health) | 24 | (34%) |
| Foundation | 12 | (17%) |
| Department, institution, or organization | 11 | (16%) |
| Pharmaceutical industry | 1 | (1%) |
| Explicit statement that there was no funding | 17 | (24%) |
| Not reported | 12 | (17%) |
i
Reviews could assess multiple conditions/indications
ii
Reviews could include both direct, pairwise, comparisons and network meta-analyses
iii
Reviews could report following multiple different guidance documents
iv
Reviews could report multiple different sources of funding