UCL Great Ormond Street Institute of Child Health


Great Ormond Street Institute of Child Health


Sample Size Estimation and Power Calculations with Excel

10:00 am to 4:30 pm, 12 February 2020

This course gives the basics of sample size estimation. It will be of use to those embarking on a research project and who are perhaps trying to complete ethics and grant application forms. Both precision and power estimation approaches are covered.

Event Information

Open to







Centre for Applied Statistics Courses


238: ICH, Wellcome Trust Building
30 Guildford Street
United Kingdom

The concepts of sample size estimation are introduced, including when and why this might be necessary. Formulae are presented and discussed. An accompanying weblink is introduced which hosts excel sheets pre-programmed to facilitate use of the formulae. In the morning the precision-based approach to sample size estimation is introduced, whereby the numbers are selected to produce a confidence interval for the relevant estimate with a specified width. In the afternoon we progress to the more traditional power calculations that aim to give the sample required to determine a specified difference with selected power and significance levels. All terminology will be explained as it is introduced in the sessions.

Sample size estimation is discussed for the following measurements:

  • Means
  • Proportions/ percentages
  • Time to event data
  • Rates
  • Measures of agreement

Delegates are welcome to bring their own laptops and access to the UCL Guest network will also be provided. Everyone wishing to bring their own computer should ensure Microsoft Excel (or alternative compatible software) is installed before attending.


Course fees

External Delegates (Non UCL)£175.00
UCL Staff, Students, Alumni (incl. ICH/GOSH)£87.50 *
Staff and Doctoral Students from ICH/GOSHFREE †

* Valid UCL email address and/or UCL alumni number required upon registration. Please note, this category does not include hospital staff unless you hold an official contract with the university.

† Limited free spaces available. If there are no free places remaining, Staff and Doctoral Students from ICH/GOSH can still register at the UCL rate.

Prices include printed course materials, refreshments (and lunch for non-ICH/GOSH participants 12.45pm - 1.45pm)


Please note that no refunds will be given for non-attendance or cancellations made within 5 working days of the start of the course. For delegates attending courses on funded places, a £50 fee will be charged for late cancellation, non-attendance or partial-attendance. This fee is needed to cover printing, catering, etc. costs that are ordered no later than 5 days before the course and are based on the number of people registered at that point in time. 

Future Dates (10.00am-4.30pm)
12 February 202010.00am - 4.30pm^Book Now
TBC10.00am - 4.30pm^Subscribe to general mailing list
^Registration period is 9.45am-10.00am with tea and coffee served and the course will start promptly at 10.00am
Future Dates (evening)
TBC5.30pm-8.15pm^Subscribe to general mailing list
^Registration period is 5.15pm-5.30pm with tea and coffee served and the course will start promptly at 5.30pm

“Excellent as always. This is my 6th course and all were extremely useful and relevant"

"Very good course and exactly what I needed. Course material is very good though and will be a helpful reminder in the future.”

"Really well paced course, very useful being provided with the excel spreadsheets, friendly and experienced staff, highly recommend all of these courses!”

"I really like the courses because they are well explained and the material is clear.”

"I really enjoyed the training session. I can say that the course is timely because I am developing a proposal where I would apply the knowledge gained in this training to calculate my sample size for the study. Keep it up”