All Outputs (3)

The just-about-right pilot sample size to control the error margin (2023)
Journal Article
Obodo, S., Toher, D., & White, P. (2023). The just-about-right pilot sample size to control the error margin. International Journal of Statistics and Probability, 12(3), https://doi.org/10.5539/ijsp.v12n3p1

In practice, the required sample size for a two-arm randomised controlled trial cannot always be determined pre-study with great accuracy. This lack of accuracy has economic, ethical and scientific implications. The sample size for a pilot study is... Read More about The just-about-right pilot sample size to control the error margin.

Estimation of the two-group pilot sample size with a cautionary note on Browne’s formula (2021)
Journal Article
Obodo, S., Toher, D., & White, P. (2021). Estimation of the two-group pilot sample size with a cautionary note on Browne’s formula. Journal of Applied Quantitative Methods, 16(3),

Using data obtained from a pilot study, Browne (1995) proposed a procedure for estimating the sample size needed for a definitive two-arm randomised controlled trial when the minimal important difference is specified. Simulations confirm these findi... Read More about Estimation of the two-group pilot sample size with a cautionary note on Browne’s formula.

Investigating Browne's method (2021)
Presentation / Conference
Obodo, S., Toher, D., & White, P. (2021, September). Investigating Browne's method. Poster presented at Statistics at Bristol: Future Reserach and You 2021, Bristol

Results supports Browne’s procedure of pilot sample size determination. However the data reveals that the procedure underestimates and overestimates sample size. Fig. 1 shows 𝛼 and 𝛽 have no practical effect on degree of excess which increases as... Read More about Investigating Browne's method.