Mr Lim Yong Hao

Mr Lim Yong Hao

Senior Research Analyst
Health Outcomes & Medical Education Research (HOMER),
Education Development Office
National Healthcare Group (NHG)



Best Practices In Scale Development And Validation
Date: 22 September 2017, Friday
Time: 10.45am – 5pm
Synopsis: Scales are instruments used to measure health status, attitudes, perceptions and emotions. Some of the common scales used in family medicine and primary care setting are: Medical Interview Satisfaction Scale, Maslach Burnout Inventory, Patient Reported Experiences and Outcomes of Safety in Primary Care (PREOS-PC). The process of developing and validating scales involves three stages: conceptualizing, operationalizing and evaluating. While these three stages are also present in the development and validation of assessment tools, there are distinct differences between the two processes. Understanding the details and differences of the process of developing and validating scales will allow for better appreciation of the usefulness and relevance of scales in family medicine and primary care.

At the end of the workshop, participants should acquire basic knowledge in:
1. Thinking and defining what to measure (Conceptualization)
2. Writing and adapting items and questions (Operationalization)
3. Testing the validity of the items and questions (Evaluation)

Participants will be able to understand and interpret research findings on scale development, design simple scales and adapt existing scales using the best practices shared during the workshop.


1.1 Introduction to scale development
– What are scales?
– When do we use scales? (with examples)
1.2 Conceptualizing what to measure
– What are different ways to conceptualize and define what we are measuring?
1.3 Operationalizing what we want to measure
– How to write and adapt items?
– How to spot problematic items?
2.1 Putting your items together into a scale
– What are the considerations when putting items into a scale?
– What are different modes of administration?
2.2 Pre-testing scales
– What can we test before we administer our scales?
– How can we test them?
3.1 Evaluating scales
– How to test the validity of scale items?
– What is factor analysis?
3.2 Concluding discussion


Yong Hao is a senior research analyst with HOMER, a unit within NHG Education Office that looks into and builds capacity in Health Professions Education research. In HOMER, he is involved in research and evaluation projects related to undergraduate and graduate medical education. These projects include analysing assessment data collected by the various residency programmes to better understand residency training; developing faculty evaluation tools; and evaluating the impact of training programmes.

He completed his Master of Social Sciences (Psychology) with a concentration in Quantitative Methods at National University of Singapore. Prior to that, he worked on research and evaluation in health promotion as well as taught psychology undergraduates research methods and statistics. His research interests include evaluating statistical methods when data is suboptimal (e.g. non-normality, small sample sizes, missing data, etc.); applying structural equation modelling; the feedback process in teaching and learning; educational assessments in health professions education; and increasingly, interprofessional collaboration and education and work based learning.