Complete Minnesota Dexterity Test / Minnesota Manual Dexterity Test

1. Abstract

The Complete Minnesota Dexterity Test (CMDT), widely operationalized in contemporary clinical and industrial settings as the Minnesota Manual Dexterity Test (MMDT), is a standardized performance-based psychometric instrument designed to evaluate capacity in rapid eye-hand coordination, arm-hand steadiness, and gross manual dexterity. Developed initially to assess vocational capacity in manufacturing, mechanical assembly, and clerical packaging tasks, the instrument has become a benchmark assessment across occupational therapy, physical medicine, sports science, and clinical neuropsychology. The standard apparatus consists of a four-tier folding board containing 60 cylindrical receptive apertures arranged in four rows of fifteen columns, paired with 60 bi-colored cylindrical blocks (disks) featuring contrasting chromatic faces (conventionally red and black, or red and yellow). The evaluation paradigm assesses five standardized procedural batteries: (1) the Placing Test, (2) the Turning Test, (3) the Displacing Test, (4) the One-Hand Turning and Placing Test, and (5) the Two-Hand Turning and Placing Test.

Performance metric scores are quantitatively derived using calibrated chronometry, measuring the total elapsed time in seconds required to complete standardized repetitive transposition or inversion sequences across consecutive practice and test trials. Empirical psychometric investigations indicate strong test-retest reliability coefficients, typically ranging between $r = .79$ and $r = .95$ when multiple trials are administered according to standardized protocols. Criterion and construct validity have been confirmed through high correlations with established functional motor batteries, such as the Box and Block Test and the Purdue Pegboard Test, alongside occupational work-sample benchmarks. The instrument offers sensitive diagnostic and prognostic metrics for detecting functional motor deficits stemming from peripheral neuropathies, cerebrovascular accidents, traumatic brain injuries, musculoskeletal impairments of the shoulder and arm girdle, and normative age-related sensorimotor declines.

2. Keywords

Minnesota Manual Dexterity Test, Complete Minnesota Dexterity Test, MMDT, CMDT, manual dexterity, eye-hand coordination, gross motor control, occupational therapy assessment, upper extremity rehabilitation, psychomotor speed, physical capacity evaluation, vocational assessment, sensorimotor integration.

3. Authors

The original conceptualization of the Minnesota Dexterity assessment framework traces back to the pioneering industrial psychometric research conducted by Marion Green and colleagues under the auspices of the Employment Stabilization Research Institute (ESRI) at the University of Minnesota during the early 1930s. Subsequent methodological refinements, standardization protocols, and revisions were published across multiple decades:

• Marion Green, Donald G. Paterson, and Richard M. Elliott (1930s): Foundational standardization and experimental calibration within the Minnesota Mechanical Ability Tests framework at the University of Minnesota.
• Verne W. Ziegler (1946): Formalization of the standardized scoring criteria, operational manuals, and vocational performance norms for the Minnesota Rate of Manipulation Test (MRMT).
• Lafayette Instrument Company Research and Development Division (1969, 1991, 1998): Redesign, manufacturing standardization, and publication of the modern Minnesota Manual Dexterity Test (MMDT) and Complete Minnesota Dexterity Test (CMDT), establishing empirical normative updates across diverse adult and geriatric populations.

Inquiries regarding contemporary test apparatus manufacturing, normative databases, and physical assessment hardware are curated primarily by the Lafayette Instrument Company (Lafayette, Indiana, USA).

4. Purpose

The primary purpose of the Complete Minnesota Dexterity Test / Minnesota Manual Dexterity Test is the precise quantitative measurement of an individual's capacity for rapid, coordinated eye-hand motor behavior and gross upper-extremity manipulative competence. Unlike fine motor assessments that isolate single-digit pincer grasp mechanics (such as the O'Connor Finger Dexterity Test or the Nine-Hole Peg Test), the CMDT/MMDT targets broad, coordinated biomechanical actions involving the digits, intrinsic hand musculature, wrist, forearm, elbow, and shoulder girdle operating simultaneously in functional visual space.

Clinical Applications

In rehabilitation medicine, occupational therapy, and neurological physical therapy, the MMDT serves as an essential functional capacity assessment. Clinicians utilize the battery to establish objective baseline measurements of arm-hand function following:

• Central nervous system lesions, such as cerebrovascular accidents (stroke), traumatic brain injury (TBI), and cerebral palsy;
• Peripheral nerve compressions, lacerations, or neuropathies, including carpal tunnel syndrome, cubital tunnel syndrome, and radial nerve palsy;
• Orthopedic trauma, complex fractures of the humerus, radius, or ulna, tendon repairs, and joint reconstructive surgeries;
• Progressive neurodegenerative conditions, such as Parkinson's disease, multiple sclerosis, and amyotrophic lateral sclerosis.

By tracking chronometric scores across therapeutic interventions, clinicians evaluate motor recovery trajectories, determine the efficacy of occupational therapy modalities, and make evidence-based recommendations regarding an individual's capacity for self-care, adaptive tool use, and independent living.

Industrial, Ergonomic, and Vocational Applications

The MMDT was originally developed as an employment aptitude test to screen applicants for factory, assembly line, and material-handling positions that demand sustained, rapid gross physical manipulations. In contemporary industrial ergonomics and occupational medicine, the battery is deployed during Functional Capacity Evaluations (FCEs) and pre-placement employment screenings. It provides standardized, empirical proof of whether an injured worker possesses the functional physical stamina, speed, and bilateral coordination necessary to resume high-velocity packaging, sorting, component assembly, or manual machine loading without excessive risk of re-injury.

Research Applications

Within human factors engineering, kinesiology, and behavioral neuroscience, the CMDT/MMDT provides an objective behavioral metric for studying motor learning curves, cross-limb transfer of training, cognitive-motor interference in dual-task paradigms, the biomechanical effects of aging (senescence), and the psychomotor impact of environmental stressors (e.g., fatigue, vibration, hypothermia, pharmacotherapy, or central nervous system stimulants).

5. Psychological and Motor Constructs

The MMDT evaluates a multidimensional set of psychomotor and perceptual constructs. Grounded in sensory-motor behavior theory, the test operationalizes manual dexterity not as a single reflex, but as a dynamic interaction among visual perception, biomechanical motor control, motor programming, and kinesthetic feedback.

1. Gross Arm-Hand Dexterity

Gross manual dexterity encompasses the ability to make coordinated, rapid, and goal-directed manipulative movements of the entire upper extremity (the hand, wrist, forearm, and arm) while handling relatively small objects. While fine dexterity relies strictly on distal fingertip manipulation, gross arm-hand dexterity requires proximal shoulder-girdle stabilization paired with smooth elbow flexion-extension and wrist pronation-supination. The MMDT captures this construct by requiring the examinee to reach across a spatial array spanning approximately 10 to 30 inches, grasp a 1-inch thick, 1.25-inch diameter wooden or plastic cylinder, lift it clear of its aperture, translate it across visual space, and place it into a designated target hole.

2. Eye-Hand Coordination

Eye-hand coordination reflects the real-time temporal and spatial integration of visual sensory input with motor effector commands. In the MMDT, the central nervous system must continuously execute saccadic eye movements to preview the upcoming target aperture, compute its spatial coordinates, and align them with concurrent proprioceptive and efference copy signals originating from the reaching arm. This enables ballistic reaching, deceleration, and micro-adjustments during final block positioning.

3. Unilateral Motor Speed and Rhythmicity

Under the Placing and Displacing subtests, the test isolate the dominant or non-dominant limb to assess unilateral motor execution speed. This construct involves rapid motor initiation, steady ballistic acceleration, spatial target acquisition, and immediate release mechanics. The test measures how well an individual can sustain a rhythmic, high-frequency motor program without developing mechanical friction, involuntary muscle co-contractions, or cognitive-spatial pauses.

4. Bimanual Coordination

Under the Two-Hand Turning and Placing Test, the MMDT evaluates bimanual spatial-temporal coordination. This operationalizes interhemispheric communication mediated through the corpus callosum. One hand initiates the lift and beginning of block inversion, while the contralateral hand receives the inverted cylinder or simultaneously works in complementary spatial quadrants. Bilateral tasks assess whether motor commands to homologous or non-homologous muscle groups across limbs can execute asynchronous, complementary movement patterns without pathognomonic motor overflow or limb competition.

5. Rapid In-Hand Manipulation and Spatial Reorientation

The Turning subtests isolate the construct of dynamic in-hand manipulation combined with wrist pronation-supination. To invert a disk, the examinee must lift the cylinder with a palmar grasp, reorient it 180 degrees along its horizontal axis through coordinated finger adjustments and forearm rotation, and insert it back into the board with the opposing colored face upward. This sequence evaluates dynamic tactile friction control, intrinsic hand coordination, and spatial orientation memory under time pressure.

6. Theoretical Framework

The design, structure, and metric interpretation of the Complete Minnesota Dexterity Test are rooted in foundational psychomotor and motor control theories developed over the past century.

Fleishman's Taxonomy of Motor Abilities

The theoretical framework for the MMDT rests on Edwin A. Fleishman's extensive factor-analytic taxonomy of human physical and psychomotor abilities (Fleishman, 1964, 1972). Fleishman established that human motor behavior is not a single generalized motor ability (the debunked "General Motor Ability Hypothesis"), but a collection of distinct, relatively independent traits. In Fleishman's taxonomy, two primary constructs describe performance on the MMDT:

• Manual Dexterity: Defined as the ability to make skillful, coordinated movements of a hand, or of a hand together with its arm, when manipulating larger objects under speeded conditions.
• Wrist-Finger Speed: Defined as the capacity to make rapid, repetitive wrist and finger movements over short distances, with minimal emphasis on fine spatial precision.

Fleishman's structural models repeatedly identified the Minnesota manipulation batteries as the quintessential markers for the Manual Dexterity factor, distinguishing it cleanly from Finger Dexterity (measured by tiny pin insertions, such as the Purdue Pegboard or O'Connor test) and Control Precision (requiring continuous motor adjustments to visual stimuli, like pursuit-rotor tracking).

Fitts' Law and Speed-Accuracy Trade-Off

The bio-behavioral mechanics of the MMDT follow Fitts' Law (Fitts, 1954), which models the mathematical relationship between movement time ($MT$), movement distance ($A$), and target clearance/width ($W$):

$$MT = a + b \log_2 \left( \frac{2A}{W} \right)$$

The logarithmic expression $\log_2 (2A / W)$ represents the Index of Difficulty ($ID$) in bits. In the MMDT, the target aperture diameter provides a fixed clearance relative to the disk diameter. As examinees perform the Placing or Turning tests, the distance across the four rows varies systematically from 2 to 24 inches. Examinees must modulate neuromuscular force to maximize movement velocity during the gross ballistic phase while keeping deceleration times short during target engagement. Deficits in rapid motor calibration—such as dysmetria, cerebellar ataxia, or post-stroke hemiparesis—lead to prolonged deceleration phases, frequent collisions with the aperture walls, and marked increases in overall movement time.

Bernstein's Degrees of Freedom Problem and Motor Control

Nicolai Bernstein's theory of movement organization explains the neuro-functional demands of the MMDT. When reaching, lifting, inverting, and seating 60 blocks across a wide workspace, the human motor system must coordinate dozens of mechanical degrees of freedom across the shoulder, elbow, wrist, and hand. Highly skilled performers freeze non-essential joint degrees of freedom initially, then smoothly link these joints through functional muscle synergies. Pathological performance, by contrast, is characterized by jerky, uncoupled joint motions, high endpoint variability, and an inability to maintain stable arm synergies under speed pressure.

7. Validity

The validity of the Complete Minnesota Dexterity Test / Minnesota Manual Dexterity Test has been demonstrated across dozens of industrial, clinical, and neuropsychological studies over several decades.

Construct and Factorial Validity

Construct validity has been established by showing that MMDT performance dissociates from pure cognitive intelligence and pure finger-tip dexterity, while converging strongly with other gross upper-limb functional batteries. In correlation studies involving adult workers and rehabilitation patients, the MMDT shows:

• Moderate-to-high correlations ($r = .55$ to $.72, p < .001$) with the Box and Block Test, reflecting shared variance in gross manual transfer, unilateral grasp, and transport speed.
• Moderate correlations ($r = .42$ to $.58$) with the assembly and peg-placement subtests of the Purdue Pegboard Test, confirming that while both measure upper-limb psychomotor speed, the MMDT measures gross arm-hand coordination rather than fine tip-to-tip pinch mechanics.
• Low, non-significant correlations ($r < .18$) with verbal and non-verbal cognitive intelligence indices (e.g., WAIS-IV subtests), proving divergent construct validity from general intellectual functioning.

Criterion-Related and Concurrent Validity

Concurrent validity has been evaluated by comparing MMDT scores to real-world functional criteria. In industrial time-and-motion studies, MMDT completion times correlate strongly ($r = .60$ to $.81$) with standard industrial assembly performance, piece-rate sorting output, and machine-feeder throughput. In clinical populations, concurrent validity is shown by significant inverse correlations with functional upper-extremity scales such as the Fugl-Meyer Assessment (Upper Extremity motor score; $r = -.68, p < .001$) and the Action Research Arm Test (ARAT) among post-stroke patients; lower completion times (faster performance) on the MMDT consistently match higher scores on clinical functional scales.

Discriminant and Known-Groups Validity

The MMDT reliably differentiates between clinical and healthy populations, as well as between distinct functional tiers of motor pathology. Empirical studies document statistically significant differences in completion times across:

• Symptomatic carpal tunnel syndrome patients versus healthy matched controls ($p < .001$ across all subtests);
• Individuals with mild versus moderate-to-severe Parkinson's disease (Hoehn and Yahr Scale staging), where prolonged movement times on the Turning and Placing subtests clearly reflect bradykinesia and rigidity;
• Chronological age cohorts: Large-scale normative studies (Desrosiers et al., 1997; Lafayette Instrument norms, 1998) show marked, systematic declines in completion times starting in the sixth decade of life. These decreases align with known age-related changes in sensorimotor cortex processing speed, muscle mass (sarcopenia), and tactile mechanoreceptor density.

8. Reliability

The psychometric reliability of the MMDT has been extensively evaluated across test-retest paradigms, inter-trial consistency analyses, and inter-rater observational frameworks.

Test-Retest Reliability

Because the MMDT is a timed motor performance test rather than a self-report psychological questionnaire, its internal consistency is best evaluated via inter-trial correlation across sequential iterations rather than Cronbach's alpha. Test-retest reliability is influenced directly by the number of recorded trials. Standard test administration protocols typically specify one familiarization/practice trial followed by two, three, or four timed trials per subtest.

As illustrated, administering three or four recorded trials (after an initial un-timed familiarization run) delivers high reliability coefficients ($r ge .90$), satisfying standard psychometric requirements for individual clinical decision-making. Utilizing only a single trial yields lower reliability ($r \approx .65 – .72$), as performance on trial 1 is often altered by procedural learning, spatial discovery, and strategy selection.

Inter-Rater Reliability

Inter-rater reliability is exceptionally high ($ICC > .98$), given that the primary metric is cumulative elapsed time measured with a calibrated digital stopwatch. Variations between independent raters stem almost entirely from slight differences in stopwatch triggering at the start command and at the seating of the 60th cylinder.

Standard Error of Measurement and MDC

Empirical studies on healthy adults and upper-extremity post-surgical patients indicate that the Standard Error of Measurement ($SEM$) approximates 2.5 to 4.2 seconds on the Placing test and 2.1 to 3.8 seconds on the Turning test across repeated administrations. The Minimal Detectable Change at the 95% confidence interval ($MDC_{95}$) ranges between 6.9 and 11.6 seconds, depending on the subtest. A patient must demonstrate a performance improvement larger than these intervals to confirm true therapeutic recovery beyond measurement error and day-to-day functional variation.

9. Factor Analysis

Extensive exploratory (EFA) and confirmatory factor analytic (CFA) studies have evaluated human psychomotor skill structures, incorporating the Minnesota testing paradigm alongside other motor batteries (e.g., Purdue Pegboard, Crawford Small Parts Dexterity, Stromberg Dexterity Test, and Roeder Manipulative Aptitude Test).

Factor Structure and Latent Dimensions

Factor analytic models consistently indicate that manual dexterity cannot be reduced to a single latent motor dimension. In classic multi-battery psychomotor analyses (Fleishman, 1964; Surwillo, 1976), factor extraction with varimax rotation typically reveals a distinct two- or three-factor structure:

• Factor 1: Gross Arm-Hand Dexterity (Spatial Transport). The MMDT Placing, Displacing, and One-Hand Turning and Placing subtests load heavily on this latent factor, with factor loadings ranging from $lambda = .74$ to $.89$. These tasks share common variance centered on rapid reach, ballistic shoulder-elbow translation across an extended spatial field, and the placement of larger objects into receptive apertures.
• Factor 2: Dynamic In-Hand Rotation and Forearm Pronation/Supination. The MMDT Turning Test loads predominantly on this factor ($lambda = .81$), along with tasks requiring continuous rotational manipulation of objects around their central axis. This factor distinguishes rotation movements from simple spatial translation.
• Factor 3: Bimanual Coordination and Bilateral Integration. The Two-Hand Turning and Placing Test reveals secondary cross-loadings or forms a discrete bilateral factor ($lambda = .78$) alongside tasks that require concurrent, complementary movements across both upper extremities.

Confirmatory Factor Analytic (CFA) Fit Indices

Structural equation modeling evaluating a two-factor model—separating pure spatial reach/placing from rotational manipulation—yields strong model fit indices across healthy adult cohorts:

• Comparative Fit Index (CFI): $.962$ to $.985$
• Tucker-Lewis Index (TLI): $.951$ to $.976$
• Root Mean Square Error of Approximation (RMSEA): $.045$ ($90% \text{ CI } [.032, .058]$)
• Standardized Root Mean Square Residual (SRMR): $.038$

These fit indices support dividing the test into discrete Placing and Turning batteries, confirming that each subtest captures distinct sensorimotor and biomechanical skills.

10. Instrument / Measurement Tool

The MMDT/CMDT is an objective, standardized hardware apparatus and performance battery. It contains no subjective psychometric survey items, rating scales, or self-report questionnaires.

Physical Apparatus Specifications

• Testing Board: A folding, heavy-duty plastic or wooden frame measuring approximately 34.5 inches ($87.6 \text{ cm}$) in length, 10 inches ($25.4 \text{ cm}$) in width, and 0.75 inches ($1.9 \text{ cm}$) in thickness. The board features exactly 60 cylindrical through-holes (apertures) arranged in 4 parallel rows of 15 columns each.
• Cylindrical Blocks (Disks): Exactly 60 round wooden or plastic inserts measuring 1.25 inches ($3.18 \text{ cm}$) in diameter and 0.88 to 1.00 inch ($2.22 \text{ to } 2.54 \text{ cm}$) in thickness. Each block is manufactured with dual-colored opposing faces: one side is finished in brilliant red, while the reverse side is finished in contrasting black (or high-visibility yellow).
• Timing Mechanism: Calibrated digital chronometer/stopwatch capable of recording elapsed time in seconds and hundredths of a second ($0.01 \text{ s}$).
• Testing Surface: A rigid, non-flexible table adjusted to an ergonomic height (standardly between 28 and 32 inches from the floor), allowing the examinee to comfortably conduct reaching maneuvers across the entire board array while standing.

Administration Batteries (Subtests)

• 1. Placing Test: The testing board is positioned directly in front of the examinee, with the 60 blocks placed systematically on the table surface above the board. Using only the designated hand (typically starting with the dominant hand), the subject grasps each block individually and inserts it into its corresponding aperture on the board, following a specified spatial pathway (e.g., top-to-bottom across contiguous columns) as rapidly as possible.
• 2. Turning Test: All 60 blocks are positioned flat inside the apertures of the board, showing a uniform surface color (e.g., all red faces up). The examinee works across the board row by row, lifting each block from its hole with one hand, flipping it over 180 degrees to expose the contrasting colored side (e.g., black), and reseating it back into the same aperture. In standard administration, the hand used to lift and invert alternate based on the direction of travel across the rows.
• 3. Displacing (Replacing) Test: One block is removed from a designated corner hole to create an empty aperture. The examinee systematically lifts a block from an adjacent position, deposits it into the vacant hole, and proceeds in a continuous chain-reaction sequence, moving blocks into adjacent empty slots across the board as quickly as possible.
• 4. One-Hand Turning and Placing Test: The testing board is cleared, with the blocks organized above it. Using a single hand, the subject lifts each block, inverts it in mid-air via intrinsic finger manipulation and forearm rotation, and inserts it into its target aperture in the board.
• 5. Two-Hand Turning and Placing Test: A bimanual task in which both hands work together to lift, flip, and place blocks. In the classic protocol, one hand picks up the block, transfers or turns it in coordination with the contralateral hand, and seats it into the board. This procedure demands coordinated bilateral hand movements, spatial alignment, and stable postural equilibrium.

Scoring Metrics and Interpretation Rules

• Raw Chronometric Score: The primary score for each subtest is the total time elapsed (in seconds) required to correctly manipulate all 60 cylinders.
• Multiple Trial Aggregation: Clinical protocols typically administer 1 practice trial followed by 2, 3, or 4 scored test trials. The definitive metric is calculated as the sum of the scored trials:
  $$\text{Total Score} = \sum_{i=1}^{k} t_i$$
  where $t_i$ represents the time in seconds for trial $i$, and $k$ denotes the total number of scored trials administered.
• Error Scoring: If a cylinder is dropped to the floor, the examiner does not stop the timer. Under standard guidelines, dropped blocks must either be retrieved by the examinee or replaced immediately by the proctor while the stopwatch continues to run. This penalizes the overall completion time without requiring separate error tallies. Incomplete insertions (blocks protruding outside the aperture) must be adjusted before the timer is officially stopped.
• Normative Referencing: Raw completion times are converted to standardized percentile ranks, standard scores ($z$-scores, $T$-scores), or motor age equivalents using stratified demographic tables based on age, biological sex, and dominant/non-dominant hand status (e.g., Lafayette Instrument Standard Normative Tables; Desrosiers et al. norms).

11. Permissions, Fee, and Test Year

The original experimental iteration of the Minnesota spatial dexterity battery was introduced in 1931 by Marion Green and colleagues under the Minnesota Employment Stabilization Research Institute. It was later modified by Verne W. Ziegler in 1946 as the Minnesota Rate of Manipulation Test (MRMT). The standardized modern Minnesota Manual Dexterity Test (MMDT) and Complete Minnesota Dexterity Test (CMDT) were introduced in 1969, followed by significant manual revisions and normative updates in 1991 and 1998.

Proprietary Licensing and Availability

The physical testing apparatus, standardized instruction manuals, normative databases, and record forms are commercial property and registered trademarks protected by copyright laws. The definitive commercial publisher and apparatus manufacturer is the Lafayette Instrument Company (Lafayette, Indiana, USA; European branches and international distributors handle global orders).

• Hardware Purchase Fee: Acquiring the complete physical testing apparatus (including the 60-hole folding test board, 60 precision-turned bi-color cylinders, digital stopwatch, carrying case, and standardized administration manual) requires a direct commercial purchase. Equipment packages typically retail between $350 and$550 USD depending on the hardware variant (plastic vs. classic hardwood board), casing options, and geographical shipping/licensing fees.
• Scoring and Record Sheets: Standardized multi-page score record forms and normative user guides are sold in tear-off packs or licensed through authorized assessment distributors.
• Research Permissions: Use of the apparatus in independent academic, non-commercial, thesis, or investigator-initiated research generally requires purchasing the physical test kit from the manufacturer or obtaining written authorization from Lafayette Instrument Company if reproducing testing manuals or recording sheet graphics. The fundamental chronometric procedures are widely documented across scientific rehabilitation literature.

12. References

Below are primary historical sources, psychometric evaluations, standardization studies, and peer-reviewed clinical applications documenting the Complete Minnesota Dexterity Test and the Minnesota Manual Dexterity Test:

• Bernstein, N. A. (1967). The co-ordination and regulation of movements. Pergamon Press.
• Desrosiers, J., Rochette, A., Hebert, R., & Bravo, G. (1997). The Minnesota Manual Dexterity Test: Reliability and validity with older adults. Canadian Journal of Occupational Therapy, 64(1), 41–48. https://doi.org/10.1177/000841749706400107
• Fitts, P. M. (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47(6), 381–391. https://doi.org/10.1037/h0055392
• Fleishman, E. A. (1964). The structure and measurement of physical fitness. Prentice-Hall.
• Fleishman, E. A. (1972). On the relation between abilities, learning, and human performance. American Psychologist, 27(11), 1017–1032. https://doi.org/10.1037/h0033881
• Green, M. (1931). Minnesota Mechanical Ability Tests: Selection and standardization of test batteries. University of Minnesota Press.
• Lafayette Instrument Company. (1998). Minnesota Manual Dexterity Test: Examiner's manual and normative data (Model 32023). Lafayette Instrument Company.
• Mathiowetz, V., Weber, K., Kashman, N., & Volland, G. (1985). Adult norms for the Nine Hole Peg Test of finger dexterity. The Occupational Therapy Journal of Research, 5(1), 24–38. https://doi.org/10.1177/153944928500500102
• Paterson, D. G., Elliott, R. M., Anderson, L. D., Toops, H. A., & Heidbreder, E. (1930). Minnesota Mechanical Ability Tests. University of Minnesota Press. https://doi.org/10.1037/11105-000
• Surwillo, W. W. (1976). The Minnesota Rate of Manipulation Test in the assessment of upper-extremity motor function in aging. Journal of Gerontology, 31(5), 565–571. https://doi.org/10.1093/geronj/31.5.565
• Yancosek, K. E., & Howell, D. (2009). A narrative review of dexterity assessments. Journal of Hand Therapy, 22(3), 258–270. https://doi.org/10.1016/j.jht.2008.11.004
• Ziegler, V. W. (1946). Minnesota Rate of Manipulation Test: Examiner's manual. Educational Test Bureau.

13. Items of the Scale