Optimal Dataset Sizes for Constant Optimization in Published Theoretical Optical Formulae

ABSTRACT

Purpose: To determine the optimal number of data points required for optimization of formulae for classical lens power calculation.

Methods: A large dataset of preoperative biometric values was used to assess the convergence of formula constants in a number of established intraocular lens power calculation formulae.

Results: In formulae with a single constant, 80–100 clinical data points are sufficient to obtain convergence. The Haigis formula (three constants) requires 200–300 data points although refractive error converges more rapidly.

Conclusions: In all formulae, 80–100 clinical data points are sufficient to achieve a stable mean refractive error.

KEYWORDS:

• Lens power calculation formulae
• formula constant optimization
• customized constants
• convergence
• mean absolute refraction error

Acknowledgments

We thank all members of the IOLCon team for their contribution and work for this internet platform and all surgeons and intraocular lens manufacturers for their support of the IOLCon initiative and for uploading clinical data for formula constant optimization!

Disclaimer

No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. The authors received no financial support for the research, authorship, and/or publication of this article.