Affiliations: [a] Department of Physiotherapy and Rehabilitation, School
of Health Sciences, İstanbul Bilim University,
Istanbul, Turkey | [b] Department of Rheumatology, Cerrahpaşa Medical
Faculty, Istanbul University, Istanbul, Turkey
Abstract: BACKGROUND: Jamar dynamometer and modified sphygmomanometer
(SphM) are used to evaluate grip strength (GS) in patients with rheumatoid
arthritis (RA). However, their scores are not interchangeable. OBJECTIVES: The aim of this study was to describe the intertrial reliability
of grip strength measures obtained with Jamar dynamometer and an SphM, and
delineate the relationship of the measures obtained with these two instruments
when they were used in patients with RA. METHODS: Patients were eligible volunteers among 74 consecutive patients with definite diagnosis of RA. The
data from 61 patients were analyzed. Student's t test was used to compare GS
means of the male and female patients. Intertrial reliability was examined
using one-way repeated measures ANOVA and intraclass correlation coefficients.
The relationship between the measures was established using Pearson correlation
coefficients and inverse regression analysis. The latter allowed the generation
of conversion tables. RESULTS: GS means were not significantly different
between the genders. Both instruments demonstrated excellent intertrial
reliabilities. No significant difference was observed among the trials with
each instrument. There was a strong relationship between the instruments'
scores. This relationship was proven to be linear. Conversion equations were
calculated based on the instruments' scores. CONCLUSION: Clinicians now have a table to convert hand strength scores between Jamar dynamometer and an
SphM, and can determine the deviation from the normal in patients with RA.
