Dizziness Handicap Inventory & Activity Specific Balance Confidence Scale: Functional Outcome Measures Explained

If you're among those healthcare providers who have yet to dive into the world of Functional Outcome Measures (FOMs) when working with vestibular patients or would like to see what other healthcare providers are using, we got you covered.

In this blog we will delve into two trusted measures that have stood the test of time—ones that we've consistently relied on at North 49 being the Dizziness Handicap Inventory (DHI) and the Activity Specific Balance Confidence Scale (ABC). Over the years these measures have offered insight into how disabling patients perceive their vestibular condition to be, aiding us in designing more targeted and effective treatment plans.

What is Dizziness Handicap Inventory (DHI)

When it comes to understanding the impact of dizziness on a patient's life, the Dizziness Handicap Inventory (DHI) is our favourite. It's a comprehensive tool that evaluates perceived disability and the effects across three key domains: physical, emotional, and functional.

Dizziness Handicap Inventory Scoring

Its 25 questions are straightforward, allowing patients to indicate the extent to which their symptoms impact various aspects of their lives. The scoring system, ranging from 'yes' to 'sometimes' to 'no,' is intuitive and simple. There is a score of 4 for each 'yes', 2 for each 'sometimes', and 0 for each ‘no'. These scores, when totalled out of 100 (remember there are 25 questions with the highest score for each question being 4), provide a clear representation of the perceived disability level as follows:

• Score of 0 refers to no perceived disability.
• 1-39 refers to mild perceived disability.
• 40-69 refers to moderate perceived disability.
• 70-100 refers to severe perceived disability.

Further categorizing scores within each domain (physical, emotional, functional) can reveal specific areas significantly affected by dizziness. This helps practitioners pinpoint which aspects (i.e. emotional vs functional) may require more attention during treatment.

To categorize the 3 domains start by looking for the letter before each question. You will see a 'P', 'E', and ‘F’.

• ‘P’ stands for a question related to a physical demand. What increases the symptoms?
• ‘E’ stands for a question related to a emotional demand. Because of your symptoms, do you feel…
• ‘F’ stands for a question related to a functional demand. Because of your symptoms, is it difficult to…

Then, add up all of the scores related to each domain. The domain with the higher score indicates that the vestibular condition is having a higher impact in that area.

Additional DHI Info

Whitney (2005) proposed using a subscale composed of five DHI items for the diagnosis of benign paroxysmal positional vertigo (BPPV). Two of the five items strongly correlated with the BPPV being “getting out of bed” and “rolling over in bed”.

Zamyslowska-Szmytke (2021) also found that with the DHI:

• It was able to distinguish between patients with compensated and uncompensated vestibular dysfunction.
• Questions pertaining to positional changes were consistently scored highest in those with BPPV.
• Total scoring and subscales were correlated with anxiety and depression.

To watch a 4 min video on how to score and interpret the DHI click HERE. 

What is Activity Specific Balance Confidence Scale (ABC)

The ABC scale delves into self-perceived confidence in performing daily activities that demand balance. With 16 tasks rated on a scale from 0% (no confidence) to 100% (complete confidence), patients assess their ability to carry out these activities without losing their balance or becoming unsteady.  If they do not currently perform the activity in question they are asked to imagine how confident they would be if they had to do the activity. Also, if they normally use a walking aid to do the activity or hold onto something they are to rate their confidence as if they were using these supports.

Activity Specific Balance Confidence Scale Scoring

The averaged results (i.e. total score divided by 16) provide a comprehensive view of their confidence levels.

• <80%: Indicates reduced activity as a result of one’s balance.
• <67%: Suggests a risk of falling.
• <51%: Typically bed-bound.

Interestingly, the ABC scale exhibits a moderate correlation with the DHI, showcasing its complementary nature in understanding patients' perceptions across different vestibular disorders. (Whitney 1999)

To watch a 4 min video on how to score and interpret the ABC click HERE. 

Advantages of Functional Outcome Measures

One of the primary advantages of these measures is their simplicity and efficiency. Patients can easily complete them without consuming much time, offering practitioners quick insights into their perceived disability and confidence levels regarding daily activities.

Moreover, employing these measures at the initial visit and throughout treatment aids in tracking progress, identifying areas of improvement or regression, and assessing the impact of interventions over time. They can also help in evaluating the reliability of reported symptoms.

Conclusion

Incorporating functional outcome measures like the DHI and ABC into clinical practice significantly enhances the understanding of patients' experiences with dizziness and unsteadiness. These measures not only provide a quantitative assessment, but also empower healthcare providers to tailor treatments, monitor progress, and improve overall patient care effectively.

By leveraging these tools we can offer more personalized and targeted interventions, ultimately enhancing patient outcomes and quality of life.