A Comparison of Three Clinical Tests of Accommodation Amplitude to Hofstetter’s Norms to Guide Diagnosis and Treatment

Purpose: It has been previously documented that the push up (PU) and pull away (PA) methods overestimate accommodative amplitude (AA), while the minus lens-to-blur (MLB) method underestimates it. It has also been shown that the PU and PA methods produce similar results. We compared data obtained from these three clinically used methods to determine AA in children and young adults with base-line normative data predicted by Hofstetter. Methods: Ninety healthy subjects (mean 11.7 years, range: 6-36 and 50F/40M), split into two groups, children (mean 9.8 years, range: 6-13 and 38F/22M) and young adults (mean 25.5 years, range: 21-36 and 16F/14M), were recruited from the patient and student populations of two schools of optometry. The subjects completed three accommodative tests presented in a random order: PA, PU, and MLB methods. Results: Findings from the MLB technique varied significantly from Hofstetter’s normative values (P<0.0001). The PU (P=0.83) and PA (P=0.28) methods were similar to Hofstetter’s normative values in younger subjects. The PU (P=0.76), but not the PA (P=0.033) method was similar to Hofstetter’s normative values in the oldest adults tested. Significant differences were not found between the PU and PA values for either age group (P=0.31-Adults, P=0.56Children). Conclusions: As compared with Hofstetter’s normative values, this study suggests that the MLB technique gives a lower AA in children, while the PU and PA methods yielded consistent findings with each other and with Hofstetter’s normative values. The PU method yielded values that compared closest with Hofstetter’s normative data for the young adults tested in this study and indicates that the most consistent methods (compared to Hofstetter’s normatives) to measure AA in children is either the PU or PA methods, and the PU method for adults.