Virgil Mathiowetz

Reliability and validity of grip and pinch strength evaluations

Twenty-seven college women participated in a study to evaluate the reliability and validity of four tests of hand strength: grip, palmar pinch, key pinch, and tip pinch. Standardized positioning and instructions were followed. The results showed very high inter-rater reliability. Test-retest reliability was highest in all tests when the mean of three trials was used. Lower correlations were shown when one trial or the highest score of three trials were utilized. The Jamar dynamometer by Asimow Engineering and the pinch gauge by B&L Engineering demonstrated the highest accuracy of the instruments tested.

Effect of elbow position on grip and key pinch strength

Twenty-nine college women participated in a study to investigate the effect of elbow position on grip and key pinch strength evaluations. Standardized instructions and positioning were followed with the exception of the two elbow positions. The elbow was flexed to 90 degrees in one test condition and it was fully extended in the other. The results showed a significantly stronger grip strength measurement in the 90 degree elbow flexed position than in the fully extended position. For evaluation of key pinch strength, both hands were stronger in the elbow flexed position, but only the right hand was significantly stronger. This study supports the use of the elbow flexed position in standardized grip and key pinch evaluations.

Randomized controlled trial of an energy conservation course for persons with multiple sclerosis

Objective: To assess the short-term efficacy and effectiveness of a six-week energy conservation course on fatigue impact, quality of life and self-efficacy for persons with multiple sclerosis (MS). Methods: In this randomized controlled trial, we randomly assigned 169 persons with MS to an immediate intervention group or a delayed control group using a crossover design. The outcome measures: Fatigue Impact Scale, SF-36 Health Survey and Self-Efficacy for Performing Energy Conservation Strategies were measured before and after courses and no intervention control periods. We performed intent-to-treat analysis and compliers-only analyses using mixed effects analysis of variance models. Results: Taking the energy conservation course had significant effects on reducing the physical and social subscales of Fatigue Impact Scale and on increasing the Vitality subscale of the SF-36 scores compared with not taking the course. Additional subscales were significant depending on methods of analyses. Self-Efficacy for Performing Energy Conservation Strategies Assessment increased significantly (p<0.05) postcourse compared to precourse. Conclusions: Results support the efficacy and effectiveness of the energy conservation course to decrease fatigue impact, and to increase self-efficacy and some aspects of quality of life.

Average grip strength: A meta-analysis of data obtained with a Jamar dynamometer from individuals 75 years or more of age

Background and Purpose: Although strength diminishes with age, average values for grip strength have not been available heretofore for discrete strata after 75 years. The purpose of this meta‐analysis was to provide average values for the left and right hands of men and women 75–79, 80–84, 85–89, and 90–99 years. Methods: Contributing to the analysis were 7 studies and 739 subjects with whom the Jamar dynamometer and standard procedures were employed. Results: Based on the analysis, average values for the left and right hands of men and women in each age stratum were derived. Conclusions: The derived values can serve as a standard of comparison for individual patients. An individual whose grip strength is below the lower limit of the confidence intervals of each stratum can be confidently considered to have less than average grip strength.

Box and Block Test of Manual Dexterity: Norms for 6–19 Year Olds

The purpose of this study was to collect normative data for individuals, aged 6 to 19 years, on the Box and Block test of manual dexterity. Four hundred and seventy-one subjects (231 females and 240 males) were recruited from the seven county Milwaukee area. The subjects were from urban, suburban, and rural settings thus encompassing a wide range of socioeconomic backgrounds. Data were stratified into seven age groups of two year intervals. Results showed that increases in manual dexterity coincided with increases in chronological age. Female scores were generally better from 6 to 11 years, while males achieved slightly higher scores from 12 to 19 years. On the average right and left hand dominant subjects scored higher with their right hands although right handers were clearly more lateralized than left handers.

Effects of three trials on grip and pinch strength measurements

Abstract The purpose of this study was to evaluate possible practice or fatigue effects during grip and pinch strength measurements, using the mean of three trials method. The grip, tip pinch, key pinch, and palmar pinch strength of 49 normal subjects and 49 rehabilitation patients were measured using standard procedures. There was no evidence of a practice or motor learning effect over the three trials. In four out of the 16 measurements, there were statistically significant differences within trials, which indicated some effect of fatigue. However, the differences in means were so small that they are not thought to have clinical significance. The effects of three-trial measurements were not significantly different for the normal and rehabilitation groups.

Comparing individualized rehabilitation to a group wellness intervention for persons with multiple sclerosis

Purpose. Compare the efficacy of two interventions designed to promote health and physical activity (PA). Design. This study was a randomized clinical trial using a time series design. Subjects were randomized into individualized physical rehabilitation (IPR) and group wellness intervention (GWI). Primary questionnaires were administered twice preintervention and twice postintervention. Physical fitness and PA frequency were assessed preintervention and postintervention. Setting. Clinic based in a metropolitan area. Subjects. Fifty volunteers with multiple sclerosis. Interventions. IPR consisted of four physical therapy sessions plus three telephone calls. GWI consisted of seven educational sessions. Measures. Primary: SF-36 Health Survey, Modified Fatigue Impact Scale, Mental Health Inventory. Secondary: physical assessment, PA frequency. Analysis. Stability of primary questionnaires between the two pretests was examined. Efficacy of interventions was evaluated by multivariate analysis of variance (MANOVA) and effect sizes. Results. Primary measures were stable between pretests. MANOVA showed nonsignificant differences between interventions. Eight weeks postintervention, both groups had improved PA, fatigue, resting heart rate, and strength. Effect sizes suggested that IPR had a greater effect on preventing decline of physical health, whereas GWI had a greater effect on improving mental health. Conclusion. Preliminary evidence indicated that health and PA improved in both groups. Effect sizes suggested that participants benefited more physically from IPR and more mentally from GWI. Future research should determine whether combining therapeutic exercise with group education improves both mental and physical health.

Grip-Strength Measurement: A Comparison of Three Jamar Dynamometers:

These two studies evaluated whether three types of Jamar dynamometers measured equivalently. In study A, 26 subjects were tested on 2 types; in study B, 30 subjects were tested on 3 types. Both studies found significant differences between and among the dynamometers. Therapists can no longer assume that all versions of the Jamar dynamometer measure equivalently, and the differences should be taken into account when using normative data and when assessing treatment effectiveness. In the latter case, the same dynamometer must be used for pre- and posttesting.

Comparison of Baseline Instruments to the Jamar Dynamometer and the B&L Engineering Pinch Gauge:

This study compared different types of grip and pinch strength measurement devices to determine their inter-instrument reliability and concurrent validity. The study included 40 females and 40 males who were tested on 2 types of grip and pinch strength measurement devices using a repeated measure design. Results indicated that the Jamar and Baseline hydraulic dynamometers have acceptable inter-instrument reliability and concurrent validity (i.e., they measure grip strength equivalently) and can be used interchangeably. Thus, therapists using the Baseline dynamometer are justified in using published normative data that were collected with the jamar dynamometer. In contrast, Baseline regular and hydraulic pinch gauges did not measure tip, hey, and palmer pinch strength equivalently with the B&L Engineering pinch gauge. As a result, therapists using Baseline pinch gauges are not justified in using published normative data that were collected with the B&L Engineering pinch gauge. Therapists should not interchange different types of grip and pinch strength measurement devices unless there is evidence that they measure equivalently.

Multiple sclerosis: impact of physical activity on psychosocial constructs.

OBJECTIVES To determine the impact of physical activity (PA) interventions and experience with PA on psychosocial constructs. METHODS PA, self-efficacy, self-identity, social support, and expected PA frequency were measured pre and post intervention in 39 persons with multiple sclerosis. RESULTS The MANOVA analysis indicated that self-efficacy and expectation decreased, whereas self-identity and PA improved (P<0.05). Regressions analyses indicated pretest self-identity (beta(2)=0.44) and social support (beta(2)=0.34) were associated with PA. Posttest self-efficacy (beta(2)=0.38) and social support (beta(2)=0.31) were associated with PA (P<0.05). CONCLUSIONS The interventions and experience with PA caused changes in psychosocial constructs, which subsequently affected the correlation of these constructs with PA.