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Functional Dexterity Test

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Purpose

The FDT is a portable assessment tool that measures manual dexterity skills for functional fine motor coordination task performance in a variety of age groups.

The FDT tests dynamic in hand manipulation (rotation and shift) and functional tripod grasp patterns (3 jaw chuck) in adults and children.

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Instrument Details

Acronym FDT

Assessment Type

Performance Measure

Administration Mode

Paper & Pencil

Cost

Not Free

Actual Cost

$89.95

Cost Description

North Coast Medical

Diagnosis/Conditions

  • Multiple Sclerosis
  • Pediatric + Adolescent Rehabilitation

Key Descriptions

  • Pegboard is placed 10 cm from the edge of the table. The test begins with a practice test with the non-injured hand starting at the top, opposite side of the pegboard (i.e. left hand starts at right side of board, right hand begins at left side of board.) Each peg is turned over and reinserted in the board using a 3 jaw chuck grasp pattern. After completing the first row, the patient moves down a row and begins at the opposite side of the pegboard (zig-zag pattern). This pattern continues until all pegs have been turned. After a trial practice with the non-injured hand, the test begins with the non-injured hand followed by the injured hand.
  • Instructions: Flip all pegs in a specified zigzag pattern, first with the uninjured hand, then with the injured hand.
    Penalties:

    A 5-second penalty (each):
    -Supinating forearm to assist
    -Touching the board for assist

    A 10-second penalty:
    -Dropping a peg

    Pediatric penalties:

    A 5-second penalty (each):
    -Touching a peg against chest
    -Dropping a peg
    -Switching hands
    -Utilizing assist from the non-testing hand
  • Scoring:

    Two scores are obtained:
    (a) Net time: time, in seconds, to complete the test
    (b) Total time: time to complete test + penalty seconds

    Maximum score: 55 seconds
  • If a client exceeds 55 seconds to complete the test, it is indicative of a non-functional hand. The test may be continued for up to 2 minutes to allow the examiner to denote progress within the non-functional hand range.

Number of Items

1 item
4 trials

Equipment Required

  • Stopwatch
  • 16 cylindrical wooden pegs measuring 7/8” x 1-5/8"
  • 8” square wooden pegboard with locking cover
  • Score sheet

Time to Administer

2-5 minutes

Maximum of 2 minutes each hand, instruction and practice time. Approximately 5 minutes total time.

Required Training

Reading an Article/Manual

Age Ranges

Child

6 - 12

years

Adolescent

13 - 17

years

Adult

18 - 64

years

Instrument Reviewers

Initially reviewed by Ritu Goel, MS, OTR/L in April 2015.

Updated by Jill Linder, MHS, OTR in April 2017. 

Body Part

Upper Extremity

ICF Domain

Activity
Body Function
Participation

Measurement Domain

Participation & Activities

Considerations

  • Inconsistency has been documented with penalties and poor inter- and intra- rater reliability of results

  • Pediatric client’s grasp and movement patterns have not been adequately developed to truly measure the 3-jaw chuck prehension pattern as it is measured with adults

  • Future studies should address reliability of the FDT in children with hand injuries (Tissue, et al., 2016)
  • FDT penalties are not suitable for children because hand skills are not fully developed (Duff et al., 2015)
  • Research should expand to more diagnosis for improved generalization (Sartorio et al., 2013)
  • More studies on sensitivity and responsiveness are needed (Sartorio et al., 2013)

Do you see an error or have a suggestion for this instrument summary? Please e-mail us!

Non-Specific Patient Population

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Standard Error of Measurement (SEM)

Healthy Adults: (Sartorio et al., 2013; n = 324; mean age = 43 (+/- 17) years)

  • SEM for Net time (n = 324): 1.89 sec
  • SEM for Total score (n = 324): 2.72 sec

Minimal Detectable Change (MDC)

Healthy Adults: Calculated MDC from SEM Total score value (Sartorio et al., 2013)

  • MDC = 1.96 x 2.72 x square root of 2 = 7.54
  • MDC for net time = 1.96 x square root of 2 x 1.89 = 5.2 sec. 

Cut-Off Scores

Non-Specified Hand Injury (Aaron et al., 2003; n = 46; mean age (males) = 35 years, mean age (females) = 37 years) 

 

 

Score by Functional Level

 

Dominant injured hand

(sec)

 

Non-dominant injured hand (sec)

 

 

Range

Mean

Range

Mean

Functional

16-25

21

18-27

21

Moderately Functional

26-33

29

28-45

43

Minimally Functional

34-50

38

46-55

43

Nonfunctional

>50

93

>55

102

(Table replicated from Aaron et al, 2003)

Normative Data

Healthy Adults (Sartorio et al., 2013) 

Age Group

Sex

Non-dominant

 

 

Dominant

 

 

Net Time

 

50th

84th

97.5th

50th

84th

97.5th

20-49

M

23.2

28.0

34.0

21.4

25.5

31.2

 

F

23.1

30.4

35.8

21.9

26.7

31.8

50-59

M

27.1

34.7

40.7

24.5

31.9

38.7

 

F

32.3

37.4

43.9

27.4

34.3

43.8

60-69

M

31.7

40.0

47.2

30.4

38.1

43.7

 

F

33.8

40.6

46.8

31.2

35.9

42.9

70-79

M

38.2

51.0

57.8

31.2

42.6

50.2

 

F

38.3

45.3

48.9

37.0

42.0

43.3

(Net time = time, in seconds, to complete the test; table replicated from Sartorio et al., 2013)

 

Age Group

Sex

Non-dominant

 

 

Dominant

 

 

Total Time

 

50th

84th

97.5th

50th

84th

97.5th

20-49

M

23.2

29.8

42.4

21.5

26.7

33.7

 

F

23.9

32.6

41.2

22.0

27.3

36.6

50-59

M

27.2

35.4

48.5

24.8

32.4

42.2

 

F

32.4

43.7

54.5

27.4

34.5

43.8

60-69

M

32.2

44.2

55.0

31.2

40.4

50.7

 

F

36.4

44.1

54.4

31.6

41.2

47.2

70-79

M

41.8

51.7

62.8

40.0

49.8

52.7

 

F

42.7

50.1

54.7

41.5

48.1

51.8

(Total time = combined total time with penalty seconds added to the initial time; table replicated from Sartorio et al, 2013)

Test/Retest Reliability

Healthy Adults: (Sartorio et al., 2013)

  • Excellent test-retest reliability: ICC = 0.92; 95% CI = 0.91 – 0.93

Interrater/Intrarater Reliability

Non-specified Hand Injury (Aaron et al., 2003) 

ICC Values of Scores Obtained by 3 Raters for each trial

3 Raters

ICC(2,1)

Uninjured no penalty

Injured no penalty

Uninjured with penalty

Injured with penalty

Trial 1

0.9952

0.9959

0.7696

0.8950

Trial 2

0.9963

0.9969

0.6837

0.9085

Trial 3

0.9954

0.9989

0.6717

0.8207

Trial 4

0.9901

0.9944

0.7393

0.9328

Rating:

excellent

excellent

adequate

excellent

                                   

 Intrarater  Reliability                             

            ICC values obtained by each rater

ICC(3,1)

Uninjured no penalty

Injured no penalty

Uninjured with penalty

Injured with penalty

Rater 1

0.9465

0.9406

0.8047

0.9163

Rater 2

0.9440

0.9314

0.7241

0.9108

Rater 3

0.9441

0.9474

0.8146

0.9073

Rating:

excellent

excellent

adequate

excellent

   

Criterion Validity (Predictive/Concurrent)

Traumatic Hand Injury (Ben-Shahar et al., 1998; n = 54; mean age = 38.35 (14.47) years) 

  • Moderate correlation with Purdue Pegboard Test subtest requiring pin placement with dominant hand: Spearman correlation r = 0.51, p = 0.003 

  • Moderate correlation with Purdue Pegboard Test subtest requiring pin placement with non-dominant hand Spearman correlation r = 0.79, p = 0.000 

 

Non-specified Hand Injury (Aaron et al., 2003) 

  • Excellent for the FDT as compared to 4 individual functional tasks (buttoning, lacing, tying, and screwing a nut and bolt) for dominant hand (= -0.63, < .02) 

  • Excellent for the FDT as compared to 4 individual functional tasks (buttoning, lacing, tying, and screwing a nut and bolt) for non-dominant hand (= -0.64, < .0001)

Multiple Sclerosis

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Normative Data

Multiple Sclerosis: (Kalron et al., 2013; n = 25; mean age = 50.6 (11.4) years; disease duration = 13.4 (5.8) years) 

  • Mean (SD) Functional Dexterity Test (FDT) score: 40.3 (5.2) 

    • Mean score after control phase (OT treatment): 38.6 (4.4) 

    • Mean score after sensory training tool: 33.8 (4.9)

       

Responsiveness

Multiple Sclerosis: (Kalron et al., 2013)

  • Improved FDT time from 38.6 sec (SD = 4.4) vs. 33.8 (SD =4.9) mean difference (95% CI) 4.8 (1.8, 7.0); p = .02, following 7-week sensory re-education program

Neuromuscular Conditions

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Normative Data

Peripheral Neuropathy (Leprosy): (Melchior et al., 2007; n = 27; mean age = 50.8 (11.3) years; duration of sensory deficit = 20.6 (14.6) years) 

  • Mean (SD) FDT score (dominant hand without penalties): 30.9 

  • Mean (SD) FDT score (dominant hand with penalties): 34.4 

  • Mean (SD) FDT score (non-dominant hand without penalties): 34.5 

  • Mean (SD) FDT score (non-dominant hand with penalties): 41.5

Pediatric Disorders

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Standard Error of Measurement (SEM)

Typical Developing Children: (Tissue et al., 2016, n = 12, mean age = 11 years)                                                                                                             

                                                 

  • SEM: .04 pegs per second

Minimal Detectable Change (MDC)

Calculated MDC from SEM Total score value (Tissue, et al., 2016)

Test/Retest Reliability

Typical Developing Children: (Tissue et al, 2016)                                                 

  • Excellent test-retest reliability (ICC= .90)

Interrater/Intrarater Reliability

Typical Developing Children: (Tissue et al, 2016)     

  • Excellent interrater reliability ICC (2,1) between three raters = .99 (95% confidence interval 0.99-1.00; <.0001)

Construct Validity

Children with Hand Abnormalities: (Tissue, et al, 2016)

                                   

Excellent correlation to Jebson Hand Function Test (JHFT)  subtests:

  • Card turning                                  r = 0.72
  • Small object manipulation            r = 0.78
  • Stacking Checkers                        r = 0.74

 

Excellent correlation to JHFT subtests:

  • Feeding Simulation                       r = .66
  • Moving large light cans                r = .63
  • Moving heavy cans                       r = .65

 

Excellent correlation to ADL tasks:

  • Lacing       r = .842 dominant   r = .708 non-dominant
  • Button       r = .654 dominant   r = .807 non-dominant

Mixed Populations

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Normative Data

Mixed Populations: (McKay et al., 2017; n = 998; mean (SD) = 24.4 (7.8))

Reference values for the Functional Dexterity Test by age group and sex (seconds)

Age Group (years)

Male (mean (SD), n)

Female (mean (SD), n)

3-9

34.8 (10.2), 69

33.9 (10.1), 69

10-19

23.4 (4.3), 80

22.6 (4.9), 80

20-59

20.5 (4.5), 200

20.5 (4.0), 200

60+

25.8 (7.0), 150

25.9 (7.2), 150

Bibliography

Aaron, D. H. & Stegink Jansen, C. W. (2003). “Development of the Functional Dexterity Test (FDT): Construction, validity, reliability, and normative data.” J Hand Ther 16(1): 12-21. Find it on PubMed

Ben-Shahar, R., Kizony, R., & Nota A. (1998). “Validity of the purdue pegboard test in assessing patients after traumatic hand injury.” Work 11: 315-320. Find it on PubMed

Duff, S., Aaron, D., Gogola, G. & Valero-Cuevas, F. (2015). Innovative evaluation of dexterity in pediatrics.  Journal of Hand Therapy, 28, 144-150. Find it on PubMed.

Gogola, G. R., Velleman, P. F., et al. (2013). “Hand dexterity in children: Administration and normative values of the Functional Dexterity Test.” J Hand Ther 38(12): 2426-2431. Find it on PubMed

Kalron, A., Greenberg-Abrahami, M., et al. (2013). “Effects of a new sensory re-education training tool on hand sensibility and manual dexterity in people with multiple sclerosis.” NeuroRehabilitation 32(4): 943-948. Find it on PubMed

Lee-Valkov, P. M., Aaron, D. H., et al. (2003). “Measuring normal hand dexterity values in normal 3-, 4-, and 5-year-old children and their relationship with grip and pinch strength.” J Hand Ther 16:22-28. Find it on ScienceDirect

McKay, M.J., Baldwin, J.N., et al. (2017). Reference values for developing responsive functional outcome measures across the lifespan. Neurology, 88, 1512-1519.

Melchior, H., Vatine, J., et al. (2007). “Is there a relationship between light touch-pressure sensation and functional hand ability?” Disabil Rehabil 29(7): 567-575. Find it on PubMed

Sahin F., Atalay, N., Akkaya, N., Aksoy, S. (2017). Factors affecting the results of the functional dexterity test. Journal of Hand Therapy, 30, 74-79. Find it on PubMed.

Sartorio, F., Bravini, E., et al. (2013). “The Functional Dexterity Test: Test-retest reliability analysis and up-to date reference norms.” J Hand Ther 26(1): 62-68. Find it on ScienceDirect

Tissue, C., Velleman, P., Stegink-Jansen, C., Haenosh, Aaron, D., Winthrop, B., & Gogola, G.(2016). Validity and reliability of the functional dexterity test in children. Journal of Hand Therapy, 1-6. Find it on PubMed.