The Grooved Pegboard Test (GPT) is a test of finger dexterity that assesses both psychomotor speed and fine motor control and has shown to be relevant in gauging the performance of assembly and machine-operating type of jobs, work hardening programs, and a number of health conditions in which hand and finger performance is of primary concern. During assessment the subject is required to place 25 keyed pegs into an array of 25 slotted holes as quickly as possible (Strenge, Niederberger, & Seelhorst, 2002). The GPT is a unique dexterity assessment in that each peg has a ridge on one side and therefore must be oriented correctly to fit into a hole on the pegboard; thus the GPT requires a level of complex visual-motor coordination for successful completion not seen in other pegboard batteries (Howell & Yancosek, 2009). During assessment both hands are tested separately, with the dominant hand tested first. The clinician records in seconds the length of time required to perform the task of putting all of the pegs in the slots on the board. Other scoring entails correctly placed pins as well as the number of drops. The GPT can be completed in less than 10 minutes.
Reliability of the GPT has been addressed in several studies. Ruff and Parker (1993) reported test-retest coefficients ranging from r = 0.69 to 0.76 for the dominant hand and r = 0.68 to 0.78 for the non-dominant hand over a 6-month period (Mitrushina, 2005). A study by Wang et al. (2011) of 340 subjects ages 3 to 85 years old determined that the GPT had good test–retest reliability at r = 0.91 and 0.85 for right and left hands, respectively and that it was moderately to significantly correlated with the Purdue Pegboard Test at −0.73 to −0.78. Results also found that the GPT was both longer and more challenging for the youngest children and oldest adults. Another investigation of healthy adults (n = 66) revealed a significant main effect for gender; however, no significant interaction was observed with regard to the influence of left-hand peg placement direction (right-to-left vs left-to-right) (Fouty et al., 2015). A study by Schubert et al. (2013) found that those with olfactory impairment, which can occur after traumatic brain injury, took significantly longer to perform the GPT than those without impairment at 85.1 seconds compared with 72.2 for the unimpaired group. An examination of GPT scores of 49 medical students found that mean score for the right hand was 54.2 seconds (range 41 to 74 seconds) and for the left hand it was 57.9 seconds (range 44 to 68 seconds) (Strenge et al., 2002) Another study found moderate correlations between GPT performance and a subject’s level of alertness (i.e., tonic or phasic for both the right and left hands) at tonic 0.25 (right) and 0.10 (left) while phasic correlations were 0.31 (right) and 0.30 (left), suggesting that alertness (either tonic or phasic) plays an important role in the performance of tasks demanding attention (Strenge et al., 2002). No significant effects of age or sex were noted in that study. A sample of 191 subjects with Parkinson’s disease comparing the GPT with the Unified Parkinson’s Disease Rating Scale (UPDRS) found the strongest relationships between the place phase (both limbs) and total UPDRS motor score (affected: r = 0.60 and less-affected: r = 0.59), whereas the GPT remove phase had weak positive relationships with total UPDRS scores (affected: r = 0.31, less-affected r = 0.31) (Sage, Bryden, Roy, & Almeida,2012), suggesting that the act of placing a keyed peg may require more motor as well as other abilities.
Adapted from Lafayette Instrument Company. (2002). Grooved Pegboard Test user instructions (p. 8). Lafayette, IN.