Video created: September 23, 2015

A Standardized Mean Difference, or SMD for short, is a summary statistic used when the studies in a meta-analysis assess the same outcome but measure it in different ways.* An SMD is not tied to any specific unit of measurement, so it can be challenging to know how to interpret it, and how to use it to inform your public health decisions.
In this seven-minute video, we invite you to roll up your sleeves and conquer SMDs.

We also discuss why standardized mean differences are used in meta-analyses and how to interpret SMDs that are reported as positive or negative values.

The video uses the example of teen mental health to demonstrate how an SMD is calculated.

Greater understanding of SMDs will help you apply evidence in your practice, contributing to enhanced public health outcomes.

The National Collaborating Centre for Methods and Tools is funded by the Public Health Agency of Canada and affiliated with McMaster University. The views expressed herein do not necessarily represent the views of the Public Health Agency of Canada.

NCCMT is one of six National Collaborating Centres (NCCs) for Public Health. The Centres promote and improve the use of scientific research and other knowledge to strengthen public health practices and policies in Canada.