SCIENTIFIC/CLINICAL ARTICLES JHT READ
FOR
CREDIT #016
Reliability and Validity of a Self-report of Hand Function in Persons with Rheumatoid Arthritis Janet L. Poole, PhD, OTR/L Occupational Therapy Graduate Program Departments of Orthopaedics and Rehabilitation and Pediatrics University of New Mexico Albuquerque, New Mexico
Kenneth J. Cordova, MOT EASI Albuquerque, New Mexico
Lisa M. Brower, MOT, OTR HealthSouth Rehabilitation Hospital Albuquerque, New Mexico
Rheumatoid arthritis (RA) is a systemic, inflammatory, debilitating disease that can occur at any age. Inflammation of the synovium of the joints is a precursor in the facilitation of destruction of the tissues of the joint.1 Following the inflammatory process, the synovium becomes hypertrophic from proliferation of blood vessels and synovial fibroblasts and from multiplication and enlargement of the synovial lining layers. The destruction of the tissues progresses when the granular tissue extends into the cartilage and develops pannus. It is this tissue that is effective in the invasion and destruction of periarticular bone and cartilage at the margin between synovium and bone.1 The supporting structures of the
Supported in part by the George E. Omer, Jr., Endowment Fund, Department of Orthopaedics and Rehabilitation, University of New Mexico. Portions of this manuscript were presented at the Annual Conference of the American Occupational Therapy Association, Minneapolis, MN, May 2004 and the University of New Mexico Orthopaedics Alumni Conference, Albuquerque, NM, July 2004. Correspondence and reprint requests to Janet L. Poole, PhD, OTR/ L, Occupational Therapy Graduate Program, University of New Mexico, MSC09 5240, Albuquerque, NM 87131-0001; e-mail: . doi:10.1197/j.jht.2005.10.001
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ABSTRACT: The purpose of this study was to examine the test– retest reliability and the concurrent validity of the Duruo¨z Hand Index (DHI) in persons with rheumatoid arthritis (RA). Forty participants with RA and no other major medical problems completed the DHI, a self-report of hand function, at two points in time to assess test–retest reliability. To determine concurrent validity, participants were also administered three performance-based tests, the Arthritis Hand Function Test (AHFT), the Hand Mobility in Scleroderma Test (HAMIS), and the Keitel Functional Test (KFT), and two self-report questionnaires of functional ability, the Health Assessment Questionnaire (HAQ) and the Scleroderma Functional Assessment Questionnaire (SFAQ). Test–retest reliability intraclass correlation coefficients for the DHI ranged from 0.83 to 0.90. Scores on the DHI were significantly correlated with scores on the AHFT (rs ¼ 0.36–0.54), the HAMIS (rs ¼ 0.39), the HAQ (rs ¼ 0.78), the HAMIS (rs ¼ 0.39), and the SFAQ (rs ¼ 0.85). Scores on the DHI did not correlate with KFT scores. The results from this study show the DHI to be a reliable and valid test for hand function in persons with RA. J HAND THER. 2006;19:12–17.
joint, such as the capsule and ligaments, are also damaged in the inflammatory process which in the hand and wrist can result in the development of boutonnie`re deformities, swan-neck deformities, ulnar subluxation, and dislocation (radial deviation deformity), the latter contributing to ulnar drift of the metacarpophalangeal joints.2,3 Chronic metacarpal joint synovitis may also result in an ulnar drift deformity. Many of the deformities that occur with RA affect the ability to grip, pinch, grasp, and flex/extend the fingers and wrists, all of which compromise functional ability. This often leads individuals to adapt their daily activities or cease from performing different hobbies and activities altogether. While there are a number of performance tests that evaluate hand function, such as the Grip Ability Test,4 the Observed Hand Function Test,5 the Sequential Occupational Therapy Assessment,6 the McBain Functional Hand Assessment,7 the Jebsen Test of Hand Function,8 and the Arthritis Hand Function Test (AHFT),9 they require training, personnel, and equipment to be administered. Because of these requirements, they may be too inefficient for routine use or as outcomes in clinical trials. Therefore, self-report questionnaires, which have been used successfully to assess general functional ability, may be quick and easy ways to
assess hand use during daily tasks. One self-report questionnaire, specific to hand function, that has been used with individuals with RA, is the Duruo¨z Hand Index (DHI).10 The DHI consists of 18 questions divided into five categories (kitchen, dressing, hygiene, office, and other). Each item is scored separately on a Likert scale ranging from 0 (without difficulty) to 5 (impossible). Scores from the five total categories are summed to yield a total score ranging from 0 to 90. The DHI takes about 3 minutes to complete. In a study of 68 persons with RA, the DHI demonstrated an interrater reliability intraclass correlation coefficient (ICC) of 0.96.10 The scale was also found to correlate with visual analog scales of functional ability10 and pain,11 joint swelling and tenderness, and joint motion.11 In another study, the DHI was found to be a responsive measure after surgery for the RA hand.12 The DHI is practical because it is comprehensive, precise, simple to administer, and requires minimal professional time and money. However, none of the studies examined the validity of the DHI compared to actual performance-based tests of hand function. Therefore, the purpose of this study was to examine the test–retest reliability and the concurrent validity of the DHI in persons with RA using performance tests and self-reports of hand function.
METHODS
and applied dexterity.9 The hand strength section includes grip strength measured with an adapted sphygmomanometer and pinch strength measured with a pinch meter. The dexterity item is the time it takes to insert and remove nine pegs from a pegboard. The applied dexterity test consists of five timed items (buttoning, lacing a shoe and tying a bow, putting coins into a slot, opening and closing safety pins, and cutting putty with a knife and fork). The applied strength items (lifting a tray of tin cans and pouring water) are scored based on the total number of tin cans lifted (0–12) and the total amount of water lifted in the pitcher (0–2000 mL). The AHFT has been shown to be reliable and valid for persons with RA.9,14 Keitel Functional Test The Keitel Functional Test (KFT) is used to assess joint limitations.15 In this study, only the nine hand and wrist items were used which measured finger flexion, wrist extension and flexion, forearm pronation and supination, and elbow flexion. There are specific scoring criteria for each item.15 Scoring is done separately for each upper extremity with a total possible score of 21 (11 per extremity). Lower scores indicate less impairment in ROM. The KFT was designed for use in persons with RA, and the literature has shown it to be reliable15,16 and valid17 for this population.
Subjects This study included 40 subjects who had been diagnosed with RA according to The American College of Rheumatology Criteria for RA.13 Subjects were excluded if they had more than one rheumatic disease or other chronic diseases such as cardiac conditions, stroke, brain injury, and/or Parkinson’s. Exclusion of subjects also occurred if they were unable to read English. The sample was one of convenience. All subjects completed a written consent form and were tested at their convenience. The subjects consisted of 34 females and six males. The ages of the participants ranged from 22 to 76 years with a mean age of 49.5 years. Disease duration ranged from 1 to 42 years with a mean disease duration of 13.1 years. The hand dominance of the participants were as follows: 38 were right handed, one was left handed, and one was ambidextrous.
Measures
Hand Mobility in Scleroderma Test Hand Mobility in Scleroderma Test (HAMIS) is a performance test that was designed to examine the effects of systemic sclerosis on hand ROM.18,19 The HAMIS consists of nine items: finger flexion and extension of all joints, abduction of the thumb, pincer grip, finger abduction, wrist flexion and extension, and pronation and supination of the forearm. The HAMIS has been recently validated in persons with RA.20 It was used in the present study in addition to the KFT because the HAMIS measures a variety of joint motions in the fingers while the KFT only measures finger and thumb flexion. Each item is scored on a scale of 0 (no impairment) to 3 (cannot do), which yields a score of 27 for each hand. Health Assessment Questionnaire
Arthritis Hand Function Test The AHFT is a performance-based test examining the ability to use ones’ hands during daily life tasks. This standardized test consists of 11 items including grip and pinch strength, dexterity, applied strength,
Health Assessment Questionnaire (HAQ), a selfreport measure, consists of eight categories of daily living: dressing and grooming, arising, eating, walking, hygiene, reach, grip, and outside activity.21 These eight categories consist of two to three questions each. Subjects are to indicate how much January–March 2006
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difficulty they have with each item from 0 (no difficulty) to 3 (cannot do). The highest scores from each category are summed, and then the total score is divided by eight. This yields a disability index from 0 (less disabled) to 3 (more disabled). The HAQ has been considered the ‘‘gold standard’’ to measure functional ability in persons with RA and has been shown to be reliable21 and valid.16,22
The ICCs were calculated to examine the test–retest reliability of the DHI. The ICCs assess the degree of agreement between the scores for a test, the DHI, at two points in time.24 Spearman rho correlation coefficients were also calculated to estimate the concurrent validity of the DHI with the AHFT, KFT, HAMIS, HAQ, and SFAQ.
RESULTS Scleroderma Functional Assessment Questionnaire Scleroderma Functional Assessment Questionnaire (SFAQ) is a self-report questionnaire developed for individuals with scleroderma to assess function through the course of the disease.23 The SFAQ has also been recently validated in persons with RA.20 The questionnaire consists of 11 items covering grooming, dressing, toileting, lifting, unscrewing lids from jars, walking up stairs, and manipulating coins. Scoring for the questionnaire is on a 4-point scale from 0 (able to perform in normal manner) to 3 (impossible). Scores are summed to yield a total score. Lower scores reflect more ability and higher scores reflect more disability.
Procedures To determine test–retest reliability of the DHI, subjects were asked to complete the DHI a second time within one week of the initial testing session and return the completed form to the primary investigator. The time to administer the battery of tests was approximately 45 minutes to one hour. Upon return of the DHI form to the primary investigator, subjects were paid 10 dollars for their time and participation. To determine the concurrent validity of the DHI, subjects completed three performance tests of hand function: the AHFT, the KFT, and the HAMIS. They also completed the two self-report questionnaires regarding the ability to perform daily tasks: the HAQ, and the SFAQ. The total testing took approximately 45 minutes to one hour to complete.
Data Analysis Descriptive statistics were calculated for the demographic variables for the sample and all measures.
Table 1 shows the means and standard deviations for both trials of the DHI. The test–retest reliability of the DHI was calculated in 39 subjects, as one participant did not return the questionnaire. According to Portney and Watkins,24 ICC values above 0.75 are considered good reliability, whereas values below 0.75 represent poor to moderate reliability. The ICCs range for the test–retest reliability of the DHI between time 1 and time 2 was from 0.83 to 0.90 (Table 1). The kitchen section had the highest ICCs at 0.90, and the office section had the lowest ICCs at 0.83. The ICC for total DHI scores was 0.89, which shows good to excellent overall reliability. Table 2 shows the descriptive statistics for the performance of 40 subjects on the AHFT, KFT, HAMIS, HAQ and SFAQ. Due to many items on the AHFT, items were combined to create three separate scores for strength, dexterity, applied dexterity, and applied strength. The scores for grip, two-point pinch, and three-point pinch for each hand were summed to create a strength total. Dexterity was created by summing the scores in seconds for the pegboard dexterity, and scores for the five applied dexterity items were summed to yield a total applied dexterity score. The total applied strength section is the sum of pouring water and lifting can items on the AHFT. This score was obtained by converting the ounces of soup cans to milliliters and multiplying by the number of cans lifted. This score was then added to the milliliters of water that was poured from the pitcher to obtain a total applied strength score. The scores for the AHFT items suggest mild to moderate impairment when compared to the scores for nondisabled adults reported on the AHFT manual.25 Scores on the KFT and HAMIS suggest moderate joint limitations while scores on the HAQ and SFAQ suggest minimal functional disability.
TABLE 1. Means, Standard Deviations, Range, and Test–retest Reliability of the DHI for Rheumatoid Arthritis (n = 39) Time 1 DHI
Mean (SD)
Kitchen (0–40) Dressing (0–10) Hygiene (0–10) Office (0–10) Other (0–20) Total (0–90)
10.55 2.18 1.55 2.05 4.90 21.23
(8.50) (2.31) (1.89) (2.33) (4.31) (17.84)
Time 2 Range 0–35 0–7 0–7 0–8 0–16 0–70
DHI ¼ Duruo¨z Hand Index; ICC ¼ Intraclass correlation coefficient.
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Mean (SD) 9.72 1.95 1.68 1.87 4.54 19.50
(9.12) (2.31) (2.13) (2.21) (4.09) (18.36)
Range
ICCs
0–33 0–8 0–7 0–7 0–16 0–65
0.90 0.87 0.88 0.83 0.84 0.89
TABLE 2. Descriptive Statistics for the Performance of 40 Subjects on the Health Assessment Questionniare (HAQ), the Keitel Functional Test (KFT), the Hand Mobility in Scleroderma Test (HAMIS), the Scleroderma Functional Assessment Questionnaire (SFAQ), and the Arthritis Hand Function Test (AHFT) (N = 40)
AHFT items Strength total (0–260 pounds) Pegboard total (0–120 sec) Applied dexterity total (0–400 sec) Total applied strength (0–5800 mL) KFT total (0–52) HAMIS total (0–54) HAQ (0–3) SFAQ (0–33)
Mean (SD)
Range
106.55 (46.53)
22.82–194.40
51.07 (17.67) 153.01 (65.95)
36.00–116.00 77.00–381.00
5025.72 (1415.47) 1035.80–5814.80 14.65 6.58 1.14 7.70
(10.05) (8.26) (0.59) (5.94)
4.00–37.00 0.00–31.00 0.00–2.25 0.00–20.00
Table 3 displays Spearman rho correlation coefficients calculated to determine the concurrent validity of the DHI with the AHFT, KFT, HAMIS, HAQ and SFAQ. According to Portney and Watkins,24 correlations ranging from 0.00 to 0.25 indicate little or no relationship; those from 0.25 to 0.50 suggest a fair degree of relationship; values of 0.50 to 0.75 are moderate to good; and values above 0.75 are considered good to excellent. The values in Table 3 reflect good to excellent correlation of the DHI with the SFAQ and the HAQ. Fair to moderate correlations were ascertained between the DHI and all AHFT scores and the HAMIS. The scores on the DHI and the KFT were not significantly correlated.
DISCUSSION The results of this study showed that the DHI is a reliable and valid tool assessing hand function in persons with RA. Test–retest reliability was found to be excellent between both trials of the DHI, which is similar to what has been found in persons with osteoarthritis26 and scleroderma.27 Partial support for validity was also established. When compared to the AHFT, the DHI demonstrated TABLE 3. Concurrent Validity of the DHI (N = 40) AHFT Strength total (pounds) Pegboard total Applied dexterity total Applied strength total KFT HAMIS total HAQ SFAQ
DHI (Spearman Rho)
p
20.54 0.42 0.36 20.52 0.23 0.39 0.78 0.85
0.01 0.007 0.02 0.01 NS 0.02 0.01 0.01
DHI ¼ Duruo¨ z Hand Index; AHFT ¼ Arthritis Hand Function Test; KFT ¼ Keitel Functional Test; HAMIS ¼ Hand Mobility in Scleroderma Test; HAQ ¼ Health Assessment Questionnaire; SFAQ ¼ Scleroderma Functional Assessment Questionnaire.
fair to moderate correlations. The applied dexterity section demonstrated the weakest correlation with the DHI. One of the items consists of cutting a piece of putty with a butter knife. Though the majority of subjects completed this item, it was one of the more difficult items and increased applied dexterity time. The strongest correlations existed amongst the selfreport questionnaires, specifically the SFAQ, followed by the HAQ. The three questionnaires have similar items. The items on the DHI and SFAQ relate to hand function, however, many of the items on the HAQ are not specific to hand function and include other items related to daily activities. Interestingly, the DHI did correlate with the HAMIS but not with the KFT. Although both the KFT and the HAMIS measure joint motion in the hand, the HAMIS assesses a greater variety of joint motions such as finger flexion, extension and abduction, and thumb opposition and abduction while the KFT only measures finger flexion. Thus, finger flexion alone may not be as important for hand function as other joint motions in the hand. Clearly, the low correlations show that joint motion does not fully predict or quantify the ability to use the hands. Other studies with the DHI showed similar findings.11,26,28 A limitation of this study may be that subjects did not have severe contractures or compromised hand function. Future studies could examine reliability and validity of the DHI in persons with more severe involvement. Future studies could also examine the tests’ ability to determine stability over long periods of time. Other considerations for future study could examine the use of the DHI with other forms of arthritis, such as systemic lupus erythematosus or psoriatic arthritis and other diseases affecting the hand, such as diabetes. Responsiveness and sensitivity of the DHI to change as an outcome of therapeutic intervention such as occupational therapy or physical therapy could also be studied.
CONCLUSION The DHI is both reliable and valid as a measure of hand function in patients with RA. The DHI is a quick and practical test and has been validated for RA, osteoarthritis, and scleroderma. Because the selfreport can cover a wider variety of tasks than a performance-based test, the DHI can assist the therapist in determining level of difficulty with various tasks and can be used as an outcome tool for intervention.
REFERENCES 1. Goronzy JJ, Weyand CM. Rheumatoid arthritis: epidemiology, pathology, and pathogenesis. In: Klippel J (ed). Primer on the Rheumatic Diseases. 11th ed. Atlanta, GA: Arthritis Foundation, 1997, pp 155–61.
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2. Melvin J. Rheumatic Disease in the Adult and Child: Occupational Therapy and Rehabilitation. 3rd ed. Philadelphia, PA: Davis Company, 1989. 3. Rizio L, Belsky MR. Finger deformities in rheumatoid arthritis. Hand Clin. 1996;22:531–40. 4. Dellhag B, Bjelle A. A grip ability test for use in rheumatology practice. J Rheumatol. 1995;22:1559–65. 5. Vliet Vlieland TPM, van der Wijk TP, Jolie IMM, Zwinderman AH, Hazes JMW. Determinants of hand function in patients with rheumatoid arthritis. J Rheumatol. 1996;23: 835–40. 6. Van lankveld W, van’t Pad Bosch P, Bakker J, Terrwindt S, Franssen M, van Reil P. Sequential Occupational Therapy Assessment (SODA): a new test to measure hand disability. J Hand Ther. 1996;9:27–32. 7. MacBain KP. Assessment of function in the rheumatoid hand. Can J Occup Ther. 1970;37:95–103. 8. Sharma A, Schumacher H, McLellan A. Evaluation of the Jebsen hand function test for use in patients with rheumatoid arthritis. Arthritis Care Res. 1994;7:16–9. 9. Backman C, Mackie H, Harris J. Arthritis hand function test: development of a standardized assessment tool. Occup Ther J Res. 1991;11:245–55. 10. Duruo¨z M, Poiraudeau S, Fermanian J, et al. Development and validation of a rheumatoid hand functional disability scale that assesses functional handicap. J Rheumatol. 1996;23:1167–72. 11. Poiraudeau S, Lefevre-Colau M, Fermanian J, Revel M. The ability of the Cochin rheumatoid arthritis hand functional scale to detect change during the course of disease. Arthritis Care Res. 2000;13:296–303. 12. Lefevre-Colau M, Poiraudeau S, Fermanian J, et al. Responsiveness of the Cochin rheumatoid hand disability scale after surgery. Br Soc Rheumatol. 2001;40:843–50. 13. Arnett F, Edworthy S, Block D, et al. The American Rheumatism Association 1987 revised criteria for the classification of rheumatoid arthritis. Arthritis Rheum. 1988;31:315–24. 14. Backman C, Mackie H. Arthritis hand function test: inter-rater reliability among self-trained raters. Arthritis Care Res. 1995;8:10–5. 15. Eberl D, Rasching V, Rahlfs V, Schleyer I, Wolf R. Repeatability and objectivity of various measurements in rheumatoid arthritis: comparative study. Arthritis Rheum. 1976;19:1278–86.
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16. Hakala M, Nieminen P, Manelius J. Joint impairment is strongly correlated with disability measured by self-report questionnaires. Functional status assessment of individuals with rheumatoid arthritis in a population based series. J Rheumatol. 1994;21:64–9. 17. Kalla A, Kotze T, Meyers O, Parkyn N. Clinical assessment of disease activity in rheumatoid arthritis: evaluation of a function test. Ann Rheum Dis. 1988;47:773–9. 18. Sandqvist G, Eklund M. Validity of HAMIS: a test of hand mobility in scleroderma. Arthritis Care Res. 2000;13:382–7. 19. Sandqvist G, Eklund M. Hand mobility in scleroderma (HAMIS) test: the reliability of a novel hand function test. Arthritis Care Res. 2000;13:369–74. 20. Poole JL, Cordova KJ. Can hand assessments designed for persons with scleroderma be valid for persons with RA? J Rheum. 2005;32:2278–9. 21. Fries J, Spitz P, Kraines G, Holman H. Measurement of patient outcome in arthritis. Arthritis Rheum. 1980;23:137–45. 22. Brown J, Kazis L, Spitz P, Gertman P, Fries J, Meenan J. The dimensions of health outcomes: a cross-validated examination of health status measurement. Am J Public Health. 1984;74: 159–61. 23. Silman A, Akesson A, Newman J, et al. Assessment of functional ability in patients with scleroderma: a proposed new disability assessment instrument. J Rheumatol. 1998;25: 79–83. 24. Portney L, Watkins M. Foundations of Clinical Research: Applications to Practice. 2nd ed. New Jersey: Prentice Hall Health, 2000. 25. Backman C, Mackie H. Arthritis Hand Function Test Manual. Vancouver: University of British Columbia, 1997. 26. Poiraudeau S, Chevalier X, Conrozier T, et al. Reliability, validity, and sensitivity to change of the Cochin Hand Functional Disability Scale in hand osteoarthritis. Osteoarthritis Cartilage. 2001;9:570–7. 27. Brower L, Poole J. Reliability and validity of the Duruo¨z Hand Index in persons with systemic sclerosis. Arthritis Care Res. 2004;51:805–9. 28. Duruoz MT, Cerraboglu L, Dincer-Turan Y, Kursat S. Hand function assessment in patients receiving haemodialysis. Swiss Med Wkly. 2003;133:433–8.
JHT Read for Credit Quiz: Article #016
Record your answers on the Return Answer Form found on the tear-out coupon at the back of this issue. There is only one best answer for each question. #1. The DHI utilizes: a. an FCE b. an inverted ADL analysis c. a visual analog d. a Likert scale #2. The DHI takes about _____ to administer: a. 3 days b. 30 days c. 3 min d. 30 min #3. Which test has traditionally been considered the "gold standard" to measure hand function in persons with RA? a. HAQ b. DHI c. KFT d. DASH
#4. Regarding reliability of the DHI: a. the overall ICC of 0.89 suggests moderate reliability b. the overall ICC of 0.89 suggests good to excellent reliability c. the low end ICC of 0.83 invalidates the DHI as a clinical tool d. the data do not allow ICCs to be calculated #5. Concurrent validity of the DHI was established by: a. the criterion of "intuitively obvious" b. comparing it to other recognized hand function tests c. an ASHT member survey/questionnaire d. test–retest performance When submitting to the HTCC for re-certification, please batch your JHT RFC certificates in groups of three or more to get full credit.
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