Practical Near Acuity Chart

Key feature of the chart:

PNAC chart
  • Encompasses print sizes from large (N80, such as newspaper headlines) to small (N5, such as a telephone directory entries)

  • Equal numbers of words were used on each line (one three, one four and one five letter word). Thus each line has an equivalent task demand having 12 letters split into 3 words

  • Related words sequences were established to make the task of establishing a near acuity threshold less onerous, more practical and relevant

  • The words used are easy to recognise by children (chosen from internet English word lists to be in the vocabulary of children in grade 4, aged 9, and above) and those with poor language and cognitive skills

  • The PNAC uses “Arial” font as it has limbs of a regular size and was designed to have a high level of legibility and proportionality. Lower case letters were used and punctuation excluded to minimise irregularities in acuity demand and clutter

  • Paragraphs of the most commonly used print sizes are located on the reverse side of the chart so reading a set size of print can be practiced once the near acuity threshold has been established. These passages can be used to determine reading speed and fluency.

More information on the design features of the PNAC >

View the journal article on the PNAC >