Lawson Classroom Test of Scientific Reasoning (CTSR)

Developed by Anton Lawson

Purpose To measure concrete and formal operational reasoning.
Format Pre/post, Multiple-choice
Duration 30 min
Focus Scientific reasoning (proportional thinking, probabilistic thinking, correlational thinking, hypothetico-deductive reasoning)
Level Intro college, High school, Middle school
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Sample questions from the CTSR:

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A. Lawson, The development and validation of a classroom test of formal reasoning, J. Res. Sci. Teaching 15 (1), 11 (1978).
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Gold Star Validation
This is the highest level of research validation, corresponding to all seven of the validation categories below.

Research Validation Summary

Based on Research Into:

  • Student thinking

Studied Using:

  • Student interviews
  • Expert review
  • Appropriate statistical analysis

Research Conducted:

  • At multiple institutions
  • By multiple research groups
  • Peer-reviewed publication

The multiple-choice questions on the CTSR (Lawson Test) were developed originally as instructor demonstrations with associated multiple-choice questions, which also asked students for their reasoning. These demonstration questions were based on previous research on student reasoning. The CTSR was given to over 500 middle and high school students. A subset of students was interviewed to ensure the whole classroom test was comparable to an individual test. Appropriate analysis of reliability and difficulty was conducted, and reasonable values found. The CTSR also underwent expert review. Correlations were calculated between CTSR score and other measures of reasoning, and adequate values found. The developers also conducted a principal component analysis to identify questions that grouped together in factors, using student responses. They found three factors: “formal reasoning”, “concrete reasoning” and “early formal reasoning”. The Lawson test has been given to several thousands of students and results published in over 14 papers.


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Language Translator(s)  
Arabic Al-Zaghal
Serbian Branka Radulović
Spanish Genaro Zavala and PERIG (Physics Education Research and Innovation Group)
Swedish Joel Andreas Ozolins

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Typical Results

The following are results from the original study, Lawson, 1978, using the test (which was the multiple-choice plus open-ended explanation version, but because the multiple choice options were based on responses from this study, results can be expected to be similar):

Grade N Mean Score Standard Deviation Range Standard Error of Measurement
8 145 5.68 3.23 1-12 1.5
9* 192 7.46 4.62 0-15 2.2
10 176 8.04 3.94 1-15 1.8
Total 513 7.41 4.27 0-15 2.0

*The 9th graders were from a different school, which was of higher economic status

Typical results from Ding 2013 presenting CTSR scores from science and engineering students across the four years of higher education at two Chinese universities. 

Typical pre-test CTSR results from Moore and Rubbo 2012 comparing science and non-science majors:

The latest version of the CTSR, released in 2000, is version 2. This is a revised version of the original multiple-choice version, released in 1978, which had 15 questions which asked students to choose the correct answer and explain their reasoning. Originally the assessment required the teacher to do demonstrations to ask the questions. The latest version of the assessment is multiple-choice, where the choices were based on students’ open-ended responses, making it nearly as reliable and much easier to administer and grade.