Objective: To identify the Dizziness Handicap Inventory [DHI] scores and items that can be differentiated in benign paroxysmal positional vertigo [BPPV] patients between posterior canal BPPV [PCB] and horizontal canal BPPV [HCB].

Materials and Methods: A prospective cross-sectional study, the study subjects were patients presented at the otolaryngological clinic at HRH Princess Maha Chakri Sirindhorn Medical Center, Srinakharinwirot University, Thailand. The setting was a tertiary otolaryngology practice. The subjects were patients diagnosed with PCB or HCB using the Dix-Hallpike test and the supine roll test. All the patients completed DHI forms at their first visit prior to consultation and at the last visit. All cases were treated with proper maneuver and followed-up until satisfactory clinical improvements and absence of positional induced nystagmus.

Results: Sixty-four patients had PCB, 50 had HCB during the study period between April 2015 and March 2017. The average DHI scores for PCB and HCB were 38.91±22.21 and 48.12±19.55 (p-value 0.022), respectively. The p-values of the differences in the average functional items, emotional items, and physical items between both groups were 0.028, 0.061, and 0.026, respectively. Significant difference in the items with p-value <0.01 were item 7 (function, difficulty reading) and 23 (emotion, depression). Significant difference with p-value <0.001 was the combination of item 7 and 23.

Conclusion: The DHI scores of BPPV were higher for HCB than PCB. Moreover, the patients with BPPV who had the positive values of items 7 and 23 may provide physicians with clue to look for HCB.

Keywords: Dizziness handicap inventory, Posterior canal, Horizontal canal, Benign paroxysmal positional vertigo