Dynamic Gait Index

Original Editor - Rachael Lowe

Top Contributors - Rachael Lowe, Laura Ritchie, Kim Jackson, Admin, Wendy Walker, Candace Goh, Rucha Gadgil, Maryellen Tighe, PT, DPT, Alexandra Stead, Lucinda hampton, WikiSysop, Scott Buxton, Karen Wilson, Vidya Acharya, Naomi O'Reilly, Tolulope Adeniji, Tony Lowe and 127.0.0.1

Introduction

The Dynamic Gait Index (DGI) tests the ability of the participant to maintain walking balance while responding to different task demands, through various dynamic conditions. It is a useful test in individuals with vestibular and balance problems and those at risk of falls.

The test includes:

• Eight items, walking on level surfaces, changing speeds, head turns in horizontal and vertical directions, walking and turning 180 degrees to stop, stepping over and around obstacles, and stair ascent and descent.
• Each item is scored on a scale of 0 to 3, with 3 indicating normal performance and 0 representing severe impairment.
• The best possible score on the DGI is a 24.

See also 4-item Dynamic Gait Index: a short form of the Dynamic Gait Index (8 items) for the clinical measurement of walking function in people with balance and vestibular disorders.

Intended Population

The DGI is particularly suitable for clinical populations where dynamic balance and fall risk are key concerns, including:

• Older People
• Parkinson's Disease
• Stroke
• Multiple Sclerosis
• Vestibular disorders
• Balance issues due to non-vestibular causes (e.g. Cerebellar ataxia)
• Brain Injury

Method of Use

8 functional walking tests are performed by the subject and marked out of three according to the lowest category which applies. 24 is the total individual score possible. Scores of ≤19/24 have been related to increased incidence of falls.

Equipment needed

• Box (Shoebox)
• Cones (2)
• Stairs
• 20' (6m) walkway, 15” (38cm) wide

Completion Time:

The test takes approximately 15 minutes to complete.

Test Protocol  

DGI components:

The DGI evaluates gait and dynamic balance across a range of task demands, from steady walking to more complex challenges involving speed changes, head movement, obstacle negotiation, and stairs. The eight components are:

1. Gait level surface _____

Instructions: Walk at your normal speed from here to the next mark 20' (6m)

Grading: Mark the lowest category that applies.

(3) Normal: Walks 20' (6m), no assistive devices, good speed, no evidence for imbalance, normal gait pattern

(2) Mild Impairment: Walks 20' (6m), uses assistive devices, slower speed, mild gait deviations.

(1) Moderate Impairment: Walks 20' (6m), slow speed, abnormal gait pattern, evidence for imbalance.

(0) Severe Impairment: Cannot walk 20' (6m) without assistance, severe gait deviations or imbalance.

2. Change in gait speed _____

Instructions: Begin walking at your normal pace (for 5'), when I tell you “go,” walk as fast as you can (for 5'). When I tell you “slow,” walk as slowly as you can (for 5').

Grading: Mark the lowest category that applies.

(3) Normal: Able to smoothly change walking speed without loss of balance or gait deviation. Shows a significant difference in walking speeds between normal, fast and slow speeds.

(2) Mild Impairment: Is able to change speed but demonstrates mild gait deviations, or not gait deviations but unable to achieve a significant change in velocity, or uses an assistive device.

(1) Moderate Impairment: Makes only minor adjustments to walking speed, or accomplishes a change in speed with significant gait deviations, or changes speed but has significant gait deviations, or changes speed but loses balance but is able to recover and continue walking.

(0) Severe Impairment: Cannot change speeds, or loses balance and has to reach for wall or be caught.

3. Gait with horizontal head turns _____

Instructions: Begin walking at your normal pace. When I tell you to “look right,” keep walking straight, but turn your head to the right. Keep looking to the right until I tell you, “look left,” then keep walking straight and turn your head to the left. Keep your head to the left until I tell you “look straight,“ then keep walking straight, but return your head to the center.

Grading: Mark the lowest category that applies.

(3) Normal: Performs head turns smoothly with no change in gait.

(2) Mild Impairment: Performs head turns smoothly with slight change in gait velocity, i.e., minor disruption to smooth gait path or uses walking aid.

(1) Moderate Impairment: Performs head turns with moderate change in gait velocity, slows down, staggers but recovers, can continue to walk.

(0) Severe Impairment: Performs task with severe disruption of gait, i.e., staggers outside 15” path, loses balance, stops, reaches for wall.

4. Gait with vertical head turns _____

Instructions: Begin walking at your normal pace. When I tell you to “look up,” keep walking straight, but tip your head up. Keep looking up until I tell you, “look down,” then keep walking straight and tip your head down. Keep your head down until I tell you “look straight,“ then keep walking straight, but return your head to the centre.

Grading: Mark the lowest category that applies.

(3) Normal: Performs head turns smoothly with no change in gait.

(2) Mild Impairment: Performs head turns smoothly with slight change in gait velocity, i.e., minor disruption to smooth gait path or uses walking aid.

(1) Moderate Impairment: Performs head turns with moderate change in gait velocity, slows down, staggers but recovers, can continue to walk.

(0) Severe Impairment: Performs task with severe disruption of gait, i.e., staggers outside 15” path, loses balance, stops, reaches for wall.

5. Gait and pivot turn _____

Instructions: Begin walking at your normal pace. When I tell you, “turn and stop,” turn as quickly as you can to face the opposite direction and stop.

Grading: Mark the lowest category that applies.

(3) Normal: Pivot turns safely within 3 seconds and stops quickly with no loss of balance.

(2) Mild Impairment: Pivot turns safely in > 3 seconds and stops with no loss of balance.

(1) Moderate Impairment: Turns slowly, requires verbal cueing, requires several small steps to catch balance following turn and stop.

(0) Severe Impairment: Cannot turn safely, requires assistance to turn and stop.

6. Step over obstacle _____

Instructions: Begin walking at your normal speed. When you come to the shoebox, step over it, not around it, and keep walking.

Grading: Mark the lowest category that applies.

(3) Normal: Is able to step over the box without changing gait speed, no evidence of imbalance.

(2) Mild Impairment: Is able to step over box, but must slow down and adjust steps to clear box safely.

(1) Moderate Impairment: Is able to step over box but must stop, then step over. May require verbal cueing.

(0) Severe Impairment: Cannot perform without assistance.

7. Step around obstacles _____

Instructions: Begin walking at normal speed. When you come to the first cone (about 6' away), walk around the right side of it. When you come to the second cone (6' past first cone), walk around it to the left.

Grading: Mark the lowest category that applies.

(3) Normal: Is able to walk around cones safely without changing gait speed; no evidence of imbalance.

(2) Mild Impairment: Is able to step around both cones, but must slow down and adjust steps to clear cones.

(1) Moderate Impairment: Is able to clear cones but must significantly slow, speed to accomplish task, or requires verbal cueing.

(0) Severe Impairment: Unable to clear cones, walks into one or both cones, or requires physical assistance.

8. Steps ______

Instructions: Walk up these stairs as you would at home, i.e., using the railing if necessary. At the top, turn around and walk down.

Grading: Mark the lowest category that applies.

(3) Normal: Alternating feet, no rail.

(2) Mild Impairment: Alternating feet, must use rail.

(1) Moderate Impairment: Two feet to a stair, must use rail.

(0) Severe Impairment: Cannot do safely.

TOTAL SCORE: ___ / 24

Scoring

A four-point ordinal scale, ranging from 0-3. “0” indicates the lowest level of function and “3” the highest level of function.

Total Score = 24

Interpretation  ≤19/24 = predictive of falls in older persons,   > 22/24 = safe ambulators

Psychometric Properties

Reliability

• Chronic stroke: The DGI showed high reliability and showed evidence of concurrent validity with other balance and mobility scales. It is a useful clinical tool for evaluating dynamic balance in ambulatory people.
• Vestibular disorders: DGI total scores, administered by using the published instructions, showed moderate inter-rater reliability with subjects with vestibular disorders. The DGI should be used with caution in this population at this time, because of the lack of strong reliability. The Functional Gait Assessment (FGA) is a modification of the Dynamic Gait Index (DGI) that uses higher-level tasks to increase the applicability of the test to people with vestibular disorders and to eliminate the ceiling effect of the original test.
• Multiple sclerosis: The DGI is a reliable functional assessment tool for multiple sclerosis (MS) that correlates inversely with timed walk, showing its concurrent validity.

Validity

The DGI, although susceptible to ceiling effects, appears to be an appropriate tool for assessing function in healthy older adults. However, a single population or finding understates its evidence base. Validity has also been established across several clinical populations:

• Chronic stroke: The DGI shows good concurrent construct validity, correlating with the Berg Balance Scale, Timed Up & Go, and gait speed.
• Vestibular disorders: A modified DGI has shown good concurrent validity with other vestibular/balance measures, and DGI scores relate to self-reported fall history in unilateral vestibular hypofunction.
• Multiple sclerosis: The DGI has demonstrated validity relative to other balance disorder scales and associates with fall history and muscle function.

• Cross-diagnostic evidence: A large multi-group study (n=794; stroke, vestibular dysfunction, TBI, Parkinson disease, gait abnormality) found consistent psychometric performance of the modified DGI, supporting its use across diverse neurological populations.

Responsiveness

In Parkinson disease, stroke and multiple sclerosis: People with modified DGI (mDGI) score > 49 points have low or minimal fall risk; People with mDGI score ≤ 49 points should be further investigated with other clinical scales before starting a balance-focused rehabilitation intervention; People scoring ≤ 29 points on the mDGI scale may need fall prevention intervention, regardless of the results of other balance clinical measures.

• Stroke: Moderate responsiveness in depicting change at 2 months & 5 months after treatment.

• MS: Scores ≤19/24 discriminate between fallers and non-fallers.

Interpretability

The DGI has established values for interpreting meaningful change:

• Minimal Detectable Change (MDC): Reported values for the DGI range from approximately 1.9 points to 4 points depending on population, with higher MDC values generally seen in stroke populations compared to community-dwelling older adults.
• Minimal Clinically Important Difference (MCID): Reported values are in a similar range, though clinicians should be cautious applying a single cut-off across all diagnostic groups, as values may differ by population. E.g. A total mDGI score improvement of 17.5 points has been identified as the threshold for a clinically meaningful change in balance and gait performance among subacute stroke patients undergoing rehabilitation.

Related Measures

• The 4-item Dynamic Gait Index, and the Functional Gait Assessment show sufficient validity, responsiveness, and reliability for assessment of walking function in people with stroke undergoing rehabilitation, but the Functional Gait Assessment is recommended for its psychometric properties.
• The modified Dynamic Gait Index (mDGI) expands on the original 8-item DGI by scoring gait pattern, level of assistance required, and time to complete each item, rather than a single 0-3 rating per item. This richer scoring system was developed to reduce the ceiling effect seen in the original DGI and to improve sensitivity to change in higher-functioning patients.
• The mDGI has since been validated and studied across multiple neurological populations, including stroke, Parkinson disease, and multiple sclerosis. A MCID of ≥ 7 points on the mDGI total score has been established for people with neurological disorders undergoing rehabilitation.

Clinical Application

Evaluating a person's performance on items of the DGI may be useful in identifying gait deviations and in evaluating gait improvements as a result of interventions.