Table 1. Randomized Clinical Trials Not Included in the Quantitative Results of the Systematic Review.

Source	No. of patients	Comparators	Main outcome	Reason for study exclusion	Main results
Babin et al,11 1984	77	Scopolamine vs meclizine vs placebo	Global vertigo, frequency of attacks	No result details, only P values; authors unavailable or could not provide additional detail	Both antihistamines better than placebo
Barzegari et al,12 2016	113	Diazepam vs methylprednisolone	Dizziness severity at 30, 60, and 120 min	Data not presented in useable form; authors unavailable or could not provide additional detail	Less severity of vertigo at 2 h with diazepam compared with methylprednisolone
Herndon et al,13 1975	17	Combination pill of pheniramine, nicotine acid, and pentylenetetrazol vs placebo	Nystagmus and vertigo scores	No results details; describes “lower” scores, but no raw numbers or data; authors unavailable or could not provide additional detail	Combination pill resulted in lower vertigo and nystagmus scores at 1 wk
Jalali et al,14 2020	117	Betahistine vs dimenhydrinate vs placebo	Scores on Dizziness Handicap Inventory and modified Berg Balance Scale	No outcomes of interest; results not presented in useable manner; authors unavailable or could not provide additional detail	Betahistine treatment resulted in greater improvement in dizziness scores
Kulcu et al,15 2008	38	Betahistine vs head and eye (modified Cawthorne-Cooksey) exercises	Multiple vertigo scales	Data presented as P values and graphs, without raw numbers or data; authors unavailable or could not provide additional detail	No difference in vertigo scores at 1 mo, but scores favored exercises at 2 mo
Massaeli et al,16 2017	100	Promethazine vs diazepam	Rate of complete resolution 15 min after injection; “duration of vertigo disappearance”	Results at unclear acute time frames; no VAS or vertigo rating; no outcomes of interest	No significant difference found regarding incidence of primary and secondary outcomes
Mulch et al,17 1976	50	High-dose vs low-dose sulpiride vs diazepam vs dimenhydrinate vs placebo	Nystagmus scores	No clinical outcomes reported, only nystagmus	High-dose sulpiride and dimenhydrinate suppressed nystagmus; diazepam, placebo, and low-dose sulpiride did not
Salvinelli et al,18 2004	156	Semont liberatory maneuver vs flunarizine vs no treatment	“Cure” and recurrence at 6 mo	Results only provided for 6-mo outcomes; authors unavailable or could not provide additional detail	Cure rate of 94% (49 of 52 patients) with Semont, 58% (30 of 52) with flunarizine, and 36% (18 of 53) with no treatment; all differences were statistically significant
Shafipour et al,19 2017	150	Diazepam vs promethazine	Vertigo VAS scores at 30, 120, and 240 min	VAS outcome was not provided with SD so could not be included in primary meta-analysis; authors unavailable or could not provide additional detail	Change in VAS at 2 h: 31.1 with diazepam vs 44.3 with promethazine; difference statistically significant
Singh et al,20 1998	100	Cinnarizine vs prochlorperazine	Scale or score not defined, but reports percentage of subjective improvement	Not enough detail in results to use in meta-analysis; author contact information unavailable	At 5 wk, the average improvement in patients treated with cinnarizine plus exercises was 97%; with prochlorperazine plus exercises, the average improvement was 100%

Abbreviation: VAS, visual analog scale.