Understanding IBT

The IBT has been developed to enable schools to measure the progress of students overtime and compare student performance with other students internationally. 

IBT Tests, Scores and Reporting

Watch the series of videos below for an explanation of IBT tests, scores and reporting.

Measurement Scales

  • There is an IBT measurement scale for each subject: English, Mathematics and Science. 
  • The achievement of a student is based on the test score for a subject, which is converted to a location on the IBT scale and expressed as a scale score. 
  • Within each subject, student achievement expressed as scale scores allows for direct comparisons of students within grades, between grades and also over time.

Achievement Bands

  • Achievement bands have been described along each IBT scale to span the range of skills and understandings demonstrated in each subject. 
  • The descriptions of achievement are divided into nine different sections called achievement bands where band 1 describes the lowest set of skills and band 9 describes the highest set of skills. 
  • Students at the top of a band have typically demonstrated all the skills in that band and at all of the bands below.  Students in the middle of a band have typically demonstrated half the skills in that band and most or all of the skills in the bands below.  For example, a student with a scale score in the middle of achievement band 5 can typically do about half of th skills at band 5, most of the skills at band 4, and almost all of the skills at bands 3, 2 and 1.
  • It is not expected that a student moves into a higher achievement band every year, due to the width of th bands but students typically move up the bands as they move through their years of school.
  • The scale descriptions provide a practical interpretation of the scale scores in terms of skill and understanding demonstrated by a student.  the bands provide levels of achievement for each subject.  Both scale descriptions and achievement bands can help teachers to more effectively target their teaching.
  • This style of reporting is used in many national and international assessment programs such as the Trends in International Mathematics and Science Study (TIMSS) and the OECD's Programme for International Student Assessment (PISA).

Select a subject below to see the band descriptions for the subject.

Percentile Ranks

Percentile ranks are included in IBT reports to allow schools to rank students.  The percentile rank indicates the percentage of students in a group who obtained the same score or lower.  This provides a precise picture of a student's standing relative to other students who have taken the test.

International Comparison

See International comparison for details.