Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jul 1;15(1):21869.
doi: 10.1038/s41598-025-08219-4.

A new proportional hazard model with applications to breastfeeding data

Yolanda M Gómez  1 , Wilson E Caimanque  2 , John L Santibáñez  2 , Rocío Zúñiga-Tapia  3 , Diego I Gallardo  4 , Marcelo Bourguignon  5
Affiliations

A new proportional hazard model with applications to breastfeeding data

Yolanda M Gómez et al. Sci Rep. .

Abstract

The World Health Organization recommends exclusive breastfeeding for the first 6 months of life, but several factors influence its cessation. Changes in breastfeeding behavior have been reported in the literature among infants at 0, 1, 3 and 5 months. The purpose of this paper is to introduce a new proportional hazards model based on the transformed-transformer method, employing the Weibull and piecewise exponential distributions as baseline models, with the aim of setting the partitions at the time when most weaning occurs. Some properties of the model, including monotonicity and quantile functions, are discussed in detail. Additionally, a regression model for censored data is presented. The parameters of the proposed distribution are estimated using the maximum likelihood approach. Some numerical illustrations of the estimators are presented with a discussion of the obtained results. Finally, two real applications related to breastfeeding in Brazil and the USA are provided to illustrate the usefulness of our proposal.

Keywords: Gradient test; Likelihood ratio test; Power function; Sample Size; Score test; Survival data; Wald test; Weibull model.

PubMed Disclaimer

Conflict of interest statement

Declarations. Competing interests: The authors declare no competing interests.

Figures

Figure 1
Figure 1
Hazard function for WPE1 model and different time partitions. Left panel: formula image and formula image with different values of formula image and formula image. Right panel: formula image and formula image with various values of formula image and formula image.
Figure 2
Figure 2
Hazard function for WPE2 model and different time partition. Left panel: formula image and formula image with different values of formula image and formula image. Right panel: formula image and formula image with various values of formula image and formula image.
Figure 3
Figure 3
Estimated K–M survival curve for covariates of brazilian breastfeeding data set.
Figure 4
Figure 4
Estimated K–M survival curve for covariates of American breastfeeding data set.
See this image and copyright information in PMC

References

    1. Zhang, C., Zhao, W., Pan, X. & Huang, A. Effects of feeding patterns during the first 6 months on weight development of infants ages 0–12 months: a longitudinal study. Sci. Rep.14, 17451 (2024). - PMC - PubMed
    1. Meek, J. Y., Noble, L. & on Breastfeeding, S. Policy statement: Breastfeeding and the use of human milk. Pediatrics150, e2022057988. 10.1542/peds.2022-057988 (2022). - PubMed
    1. Park, P. G., Heo, J. S., Ahn, Y. H. & Kang, H. G. Association between exclusive breastfeeding and the incidence of childhood nephrotic syndrome. J. Pediatr.276, 114266–6 (2024). - PubMed
    1. Kawan, M., Gregory, E. F. & Spatz, D. L. Improving breastfeeding care & support in a large, urban, pediatric primary care practice. J. Pediatr. Nurs.70, e3-8 (2023). - PubMed
    1. Shitie, A. et al. Breast problems and associated factors among lactating women in northeast ethiopia, 2022. Sci. Rep.14, 9202 (2024). - PMC - PubMed