Contrast Sensitivity testing is a great tool for clinical exams. By testing contrast vision on a routine basis, early signs of diseases are more noticeable and records are more accurate. Contrast vision is incredibly important on an everyday basis and should be tested regularly, like acuity.
PV Number charts are acceptable for testing pediatrics as well. Children 4-5 years old can be tested using a number chart and still achieve accurate results. By the time the child is 4 to 5 years old, they can, often times, understand and recognize numbers, even if they do not yet know their alphabet.