1. To determine if the effect of near-addition lenses (bifocals) is more prominent for children with high myopia progression.
2. To study how different subject characteristics such as age, gender, baseline degree of myopia, baseline near phoria and baseline lag of accommodation affect the efficacy of bifocal lens wear in myopic children.
3. To investigate the effect of incorporating near base-in prisms along with the near-addition lenses (prismatic bifocals) on myopia progression in myopic children.

Inclusion Criteria:

• Age: 8 to 13 years
• Myopia: -1.00 to -5.00 D
• Myopia progression: at least 0.50 D/yr
• Astigmatism and anisometropia: not more than 1.50 D
• Distance monocular visual acuity: 6/6 or better
• Near monocular visual acuity: 0.4 M or better
• Stereoacuity: not more than 40 sec of arc at 40 cm

Exclusion Criteria:

• Strabismus
• Ocular diseases