After baseline assessment, each patient experienced either a control condition or an experimental condition in the first phase (phase 1 group). Conditions in phase 2 were reversed.

b All change scores represent the difference in accommodative amplitude after a training condition (either experimental or control) from the immediately prior phase (i.e., baseline, control, or experimental).

over treatments, asthenopia scores improved for the control group (12.3) but remained constant for the experimental group (12.5). A sign test for ranked data’7 revealed a statistically signifi cant difference between the effects of experimental (accommodative demand lenses) and control (piano lenses) conditions (p = 0.031) with regard to asthenopia.

Table 2 shows each patient’s asthenopia

change score after exposure to experimental and control conditions. The original order of group assignment is also indicated. It is apparent that every patient showed a greater improvement in asthenopia score after accommodative demand training than after placebo training. Table 2 also shows that there was virtually no change in asthenopia score after control training, whereas more than a four point change occurred after experimental training.

Before experimental training, none of the five patients were able to clear a —2.00 D lens interposed before each eye (accommodative facility). After training, four of five patients made instantaneous accommodative changes to clear both a

—2.00 D lens and a +2.00 D lens. The one patient who failed to improve accommodative facility also showed minimal improvement in accommodative amplitude and in asthenopia reduction.

Analysis of phorias, refractive status, fusional ranges, stereopsis, and lag of accommodation showed no significant difference before and after accommodative therapy. Positive relative accommodation findings improved but the changes were not statistically significant, p < 10.

DISCUSSION

This study shows that monocular accommodative facility training results in an improve-

FIG. 2. The abscissa depicts the three phases of testing, i.e., baseline, phase 1, and phase 2. Mean accommodative amplitude for all patients in each phase (determined by minus lens to blur) is plotted on the ordinate. Open squares (0) represent patients who received experimental, accommodative training, during phase 1 and placebo during phase 2. Closed squares ~) represent patients who received the opposite condition, i.e., phase 1, control (placebo); phase 2, accommodative training.