Scale Development, Rasch Analysis and Item Response Theory

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Note re laptops:

A Windows (or a Mac operative a Windows platform) laptop is required for this course. 

The laptop will need to have SPSS installed. Most university staff and students will have access to SPSS through their institution, however it is extremely important that you check that your license works when you are not on campus at your university, as sometimes the settings/license require access to your university's VPN. If SPSS works on your laptop when you are at home then you should have nothing to worry about. Otherwise you may need to contact your relevant IT department. Wireless Internet will be available during the course.

If you do not have SPSS on your laptop, a 14-day free trial version is available via the IBM website (obviously this would need to be downloaded no sooner than 23rd Jan in order to last for the duration of the course).   

We also strongly recommend that participants bring a mouse and, if they have one, a laptop lock, although we will have some spare locks. 

ACSPRI staff will be in touch a couple of weeks prior to the course ensure all course particpants have access to an appropriate laptop (or to help obtaining one for the duration of the course) as well as providing instructions for downloading RUMM2030, which is also required for this course but only operates on WIndows machines. 

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Scales, measures and tests are commonly used in the social and health sciences as research and clinical tools. It is important that these are well designed and are reliable and valid for the purpose intended. This course provides an overview of the scale development process and the statistical techniques used including Reliability analysis, Factor Analysis and Rasch Analysis. Rasch analysis is one of the modern psychometric techniques that form part of Item Response Theory. Using specially designed software (RUMM2030) this technique allows a formal assessment of the measurement properties of scales and tests. It provides detailed feedback on all aspects of the scale including the response format, the fit of the items, item bias, unidimensionality and the spread of items across the trait being measured. Rasch analysis also allows a linear transformation of ordinal scales to interval level measures, permitting the use of parametric statistical techniques and the calculation of change scores.
 

Topics
• Introduction to measurement and testing
• Theoretical frameworks – Classical Test Theory (CTT), Item Response Theory (IRT)
• Overview of the scale development process
• Development of a test plan, item generation, selection of response format
• Assessing reliability – internal consistency (Cronbach alpha coefficient)
• Assessing dimensionality - Exploratory Factor Analysis
• Rasch Analysis, including:

 

o Preparing the data file for Rasch analysis
o Evaluating overall model fit
o Checking the response format (thresholds) and rescoring items
o Detecting misfitting items and persons
o Identifying item bias (Differential Item Functioning)
o Assessing the dimensionality and targeting of a scale
o Exporting Rasch scores to SPSS for other analyses
 

The course takes a practical applied approach (rather than mathematical) and participants are provided with detailed, hands-on experience. SPSS will be used for practical demonstrations, examples and exercises relating to reliability and factor analysis. RUMM2030 is used for the Rasch analysis training and participants will be provided with a limited licence version of the software.

 
Level 2 - runs over 5 days
Instructor: 
Course dates: Monday 2 February 2015 - Friday 6 February 2015
Course status: Course completed (no new applicants)
Week: 
Week 2
Recommended Background: 

An understanding of elementary statistics, equivalent to the syllabus of ‘Fundamentals of Statistics’ is required. This course is designed for people with little or no experience of scale development.
 

Recommended Texts: 

There is no textbook for this course but participants will be provided with a detailed set of notes. Course participants are encouraged to bring existing scales, questionnaires and/or data sets to class for discussion.
 

Course fees
Member: 
$1,800
Non Member: 
$3,230
Full time student Member: 
$1,800
Program: 
Summer Program 2015