Beginning Quantity Discrimination (BQD)

Beginning Quantity Discrimination

Beginning Quantity Discrimination (BDQ) is a standardized, individually administered measure of early numeracy that assesses a student’s ability to discriminate between two quantities. BQD is also an indirect measure of subitizing, the ability to instantly judge the number associated with a group of items. Subitization is thought to be an important precursor to math development. 

To administer BQD, the assessor presents the student with a sheet that contains a series of boxes with two patterns of dots in them and asks the student to orally name the number of dots that is the larger quantity. Since BQD assesses a student’s fluency with quantity discrimination, the measure is timed.

 

Skill Magnitude Comparison and Subitization (indirectly)
Administration Time 1 minute
Administration Schedule

Beginning of kindergarten to end of kindergarten

Score 1 point for each correctly identified number
Wait Rule If the student does not respond within 3 seconds on an item, provide the correct answer and mark a slash (/) through the number.
Discontinue Rule

0 points in the first four items (the first page)

 

Scoring Rules for BDQ

  1. Leave correct items blank. Score the student’s response as correct by leaving the item blank if the student correctly names the larger number.
  2. Slash incorrect items. Score the student’s response as incorrect by drawing a slash (/) through the item if the student states any number other than the correct answer, skips an item or hesitates with an answer after 3 seconds.
  3. Self-corrections. If the student self-corrects within 3 seconds, write “sc” over the item that had been previously slashed. Count that item as correct.