Function Test (AHFT), a new instrument for measur- ing hand strength and ... Key Words: Hand function; Standardized tests,. Rheumatoid ... Function [4], Functional Assessment of the Rheuma- toid Hand [5] .... patient arthritis center, a rehabilitation center, and a regional ... to each therapist-rater during a phone call from the.
Arthritis Hand Function Test: Inter-Rater Reliability Among Self-Trained Raters Catherine Backman and Hazel Mackie Objective. The purpose of this project was to examine the inter-rater reliability of the Arthritis Nand Function Test (AHFT), a new instrument for measuring hand strength and dexterity in adults with arthritis. Methods. Six occupational therapists (two at each of three sites) trained themselves as AHFT administrators using the test manual and training videotape. They recruited 30 adult subjects (10 at each site) with rheumatoid arthritis or osteoarthritis affecting the hands. There were 21 women and 9 men in the sample [mean age, 57.5 years; average time since diagnosis, 14.8 years). Subjects were tested twice, once by each rater from that site. Results. Inter-rater reliability ranged from 0.45 to 0.99 (Pearson r). Because subjects were tested twice, AHFT scores were examined for an order effect. Although scores on all strength items declined by the second test session, and improved for all dexterity items, only the aggregate applied dexterity score showed significant change across all three sites [P = 0.002, 0.001, and 0.031, respectively). Conclusions. These results suggest the AHFT is a reliable instrument for measuring hand strength and Catherine Backman, MS, OT(C),is Senior Instructor, Division of Occupational Therapy, School of Rehabilitation Sciences, The University of British Columbia; Hazel Mackie OT(C), is Occupational Therapist, The Arthritis Society, British Columbia and Yukon Division, Vancouver, British Columbia, Canada. Address correspondence to Catherine Backman, MS, OT(C),The University of British Columbia, School of Rehabilitation Sciences, T325-2211 Wesbrook Mall, Vancouver, BC, Canada V6T 2B5. Submitted for publication September 24, 1993; accepted May 26, 1994. 0 1995 by the American College of Rheumatology.
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dexterity that requires minimal training on the part of occupational therapist raters. Key Words: Hand function; Standardized tests, Rheumatoid arthritis; Osteoarthritis.
The hand is able to grasp, manipulate, and discriminate various objects necessary for basic self-care, work, and leisure tasks. Injury and disease affectingthe hands can negatively influence the performance of these everyday activities. Rheumatoid arthritis (RA) and osteoarthritis (OA)are two diseases that reduce the ability of people to productively use their hands. In a study on the impact of RA and OA, Yelin et al. reported that these two patient groups experienced significantly more activity losses than control subjects in household chores, shopping and errands, and leisure activities (P < 0.05) [I].Well over one-half of the RA group also experienced decreased abilities in the work domain, although this was not a finding with the OA group. In an investigation of a hand function screening tool, Recht et al. found “that degenerative diseases accounted for nearly half of all cases (of hand disability) whereas inflammatory diseases accounted for 17%” [2]. With the exception of grip strength, these studies do not specifically measure hand function, or how the ability to use one’s hands affects the performance of functional activities. Liang and Jette suggested that functional instruments used in rheumatology should employ standardized procedures and should be quantifiable, valid, reliable, and sensitive to change [3]. With these five criteria in mind, published tests of hand function were reviewed. The Quantitative Test of Upper Extremity Function [4], Functional Assessment of the Rheumatoid Hand [5], and Smith Hand Function Evaluation 0893-7524/95/$5.00
Arthritis Care and Research
Arthritis Hand Function Test 11
TABLE 1 Arthritis Hand Function Test Items Items
Strength section Grip strength, RW and LW Tip pinch strength, RH and LH Tripod pinch strength, RH and LH Dexterity section Pegboard dexterity, RH and LH
Instrumentation
Unit of measure
Adapted sphygmomanometer Pinch meter
ks
Pinch meter
kg
Nine-hole pegboard test
Time in seconds
Applied dexterity section [bilateral tasks) Lace a shoe and tie a Shoe bow Fastedunfasten four Buttons buttons Fastedunfasten two Pins safety pins Cut putty with a knife Putty and fork Manipulate four coins Coins into a slot Applied strength [bilateral tasks) Tins Lift a tray weighted with tins Pour Pour a glass of water
mm Hg
Time in seconds Time in seconds Time in seconds Time in seconds Time in seconds Number of tins Liters of water in pitcher
RH. right hand; LH, left hand.
[6] all use standardized procedures, but they have not
been adequately assessed for reliability, validity, or sensitivity to change. The Jebsen Hand Function Test [7] has been cited as a “good test for overall hand function” [8] and as an excellent test for individuals whose impairment precludes tests of fine coordination [9]. The authors reported test-retest reliability coefficients ranging from 0.60 to 0.99 (P < 0.011, depending on the test item [7], and noted that the test seemed to distinguish among medical diagnostic categories of patients. No comprehensive information has been reported regarding its validity or sensitivity to change. Each hand is tested separately, which is a disadvantage because the hands are used bilaterally for most activities. In cases of joint disease, people unable to perform a task with one hand can often complete it using two hands. The Arthritis Hand Function Test (AHFT] is a new instrument for measuring hand strength and dexterity in adults with arthritis. It consists of 11 items, including functional tasks and traditional measures of strength
and dexterity. Table 1 outlines the test items: a more complete description has been published previously [lo]. The “traditional” measures of strength and dexterity, specifically grip and pinch strength and pegboard dexterity, are widely used clinically to estimate hand function, but they were incorporated into the AHFT for reasons of consistency and comprehensiveness of testing hand function in a single test battery. More than one set of standardized procedures for grip and pinch strength exists, and no reliable norms for the instruments used in this clinical setting, and thus the AHFT, could be found. Only the nine-hole pegboard test had previously published test protocols with reliability data and norms derived from the stated procedures [ll].The AHFT is being developed in accordance with the suggestions made by Liang and Jette [3]. It has standardized procedures documented in a test manual, and it has been administered to over 100 patient subjects and 400 nondisabled subjects in accordance with the standard procedures to begin the process of evaluating its psychometric properties. Each AHFT item results in a numerical score, so the data are quantifiable. In a pilot study of 20 subjects with RA, inter-rater and test-retest reliability were demonstrated between two specially trained test administrators [lo]. Although this is promising, it is impractical to think that all future test administrators would receive the same training or give the same attention to test administration protocols. With this same group of subjects, concurrent validity was reported for the AHFT applied dexterity scores and the right hand scores for the Jebsen Hand Function Test (r = 0.63); and for the AHFT applied dexterity scores with the dexterity subscale of the Arthritis Impact Measurement Scales [12] (r = 0.71) [lo]. The internal consistency, or relationship between the dexterity sections of the AHFT, has also been examined in a group of 396 nondisabled adult subjects [13]. Like many instruments used in clinical practice, the AHFT is intended to be used by clinicians who teach themselves the administration procedures by reading the test manual. The purpose of the current investigation, therefore, was to examine inter-rater reliability between pairs of self-trained raters at different clinical sites. Sites chosen included an ambulatory care/outpatient arthritis center, a rehabilitation center, and a regional hospital.
METHODS Using the AHFT test manual and a training videotape, six occupational therapists, two at each site, trained themselves to administer the test. They were
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Vol. 8, No. 1, March 1995
Backman and Mackie
TABLE 2
TABLE 3
Arthritis Hand Function Test Inter-Rater Reliability in Pearson Correlation Coefficients for Pairs of Raters at Three Sites
Comparison of Subject Performance across Three Sites (Group Means)
Arthritis Center
Rehabilitation Center
Regional Hospital
Strength Grip RH" Grip LH Tip pinch RH Tip pinch LH Tripod RH Tripod LH
0.96b 0.91 0.95 0.85 0.93 0.95
0.97 0.98 0.77 0.88 0.89 0.97
Dexterity Peg RH Peg LH
0.69" 0.45d
Applied dexterity Shoe Buttons Pins Putty Coins Aggregate (sum] Applied strength Lifting tins Pouring
Characteristic or Test Item
Arthritis Center
Rehabilitation Center
Regional Hospital
Age (years) Years since diagnosis
58.8 14.3
59.3 14.8
54.4 15.2
0.94 0.92 0.89 0.91 0.95 0.97
Strength Grip RW (mm Hg)" Grip LHb Tip RH (kg] Tip LH Tripod RH (kgIb Tripod LHb
143.0 164.7 3.3 3.2 3.9 4.2
95.4 87.9 2.1 2.0 2.0 2.0
84.7 90.3 2.5 2.0 2.4 2.3
0.95 0.89
0.4@ 0.90
Dexterity (seconds] Peg RH Peg LH
25.0 26.7
31.9 31.7
30.0 33.6
0.82 0.87 0.90 0.87 0.86 0.91
0.95 0.90 0.75 0.67 0.80 0.95
0.95 0.96 0.98 0.98 0.96 0.98
Applied dexterity (seconds] Shoe Buttons Pins Putty Coins Aggregate score
36.7 32.8 22.0 20.4 14.7 126.6
50.0 82.1 33.2 26.2 21.4 213.0
49.7 58.1 40.3 27.0 28.4 203.5
0.99 0.94
0.85 0.99
0.91 0.65
Applied strength Tins (number of tins lifted] Pouring (volume in ml)
10.9 1,720.0
7.9 1,360.0
9.3 1,310.0
RH, right hand; LH. left hand. All P values are
