This study is aimed to determine the reliability of the Box and Block (B&B) Test for manual dexterity of upper extremity function in patients with rheumatoid arthritis (RA) and to compare the results with age- and sex-matched healthy controls, and also with available normative data.
The reliability of B&B Test was assessed within and between testers using the intraclass correlation coefficient (ICC) in patients with RA attending rheumatology clinics of Christian Medical College Hospital, India. The dexterity scores of patients were then compared with age- and sex-matched controls and the Mathiowetz's population-based normative data by Student's independent t-test.
The interrater and intrarater reliability of the B&B Test in patients with RA (n = 60) ranged from 0.92 to 0.97 and 0.91 to 0.95, respectively. The dexterity scores in patients with RA were lower as compared to the control group (dominant hand 54.87 vs. 68.18, P < 0.001; contralateral hand 52.65 vs. 65.6, P < 0.001) and population-based normative score (dominant hand 54.87 vs. 80.02, P < 0.001; contralateral hand 52.65 vs. 77.23; P < 0.001). The control group scores were also lower than the normative data. Higher age of patient, longer disease duration and higher disease activity reflected by Disease Activity Score of 28 joints (DAS-28) also correlated well with lower dexterity score.
The B&B Test is a reliable tool for assessing upper extremity function in patients with RA and the dexterity scores are lower for RA patients. The scores had correlation with age, disease duration and disease activity.