Resources for the evaluation of the effectiveness of a Kaizen program aimed at reducing Lead Time

Authors
DOI:
https://doi.org/10.47456/bjpe.v11i2.48071
Keywords:
Kaizen, Mann-Whitney U, lead time, normality test, Histogram
Abstract

This article proposes resources for evaluating the effectiveness of a Kaizen program in reducing lead time in a process for manufacturing professional uniforms. Through a case study conducted at Alpha, the periods before and after the adoption of the Kaizen program were compared, with the aim of measuring its impacts on production performance. The analysis focused on nonparametric data, using statistical tools such as descriptive statistics, histograms, time series graphs, verification of data normality with the Anderson-Darling test, as well as the application of the nonparametric Mann-Whitney test to investigate potential differences between the scenarios evaluated. The results indicated a reduction in lead time and a decreasing trend over time, although the statistical analysis did not reveal significant differences. Given the lack of standardized criteria for the objective measurement of the effectiveness of Kaizen, the study proposes a set of analytical instruments that allow for the systematic evaluation of improvements in production processes. In this way, it contributes to the advancement of research on continuous improvement, offering theoretical and practical support applicable in similar industrial contexts.

Author Biographies
  1. Thiago Loretti Arico Martins, Centro Estadual de Educação Tecnológica Paula Souza

    Possui Mestrado Profissional em Gestão e Tecnologia em Sistemas Produtivos, com ênfase em otimização de processos industriais (2024). Além disso, é certificado Master Black Belt em Lean Six Sigma, destacando-se pela sua expertise em metodologias avançadas de melhoria contínua e gestão de processos. Sua formação acadêmica também inclui graduação em Tecnologia Mecânica, Modalidade Soldagem, pela Faculdade de Tecnologia de São Paulo (2014), e especializações em Engenharia de Produção (2020) e Sistemas de Gestão Integrados da Qualidade, Meio Ambiente e Segurança do Trabalho (2022).Atualmente, Thiago é Gerente de Qualidade, Sustentabilidade e Processos na Ideal Work, onde lidera projetos de gestão da qualidade, sustentabilidade e melhoria contínua. Também leciona a disciplina de Cronoanálise no Centro Universitário Assis Gurgacz e oferece cursos livres na Austenite - Escola da Qualidade. http://lattes.cnpq.br/387182630390449

  2. Marilia Macorin de Azevedo, Centro Estadual de Educação Tecnológica Paula Souza

    Ph.D. in Engineering from the University of São Paulo (USP). Holds a Master’s degree in Quality from UNICAMP and a Bachelor's degree in Data Processing Technology from FATEC-SP. She is a permanent faculty member at the Graduate and Research Unit of the Centro Estadual de Educação Tecnológica Paula Souza (CEETEPS), working in both the Professional Master’s Program in Management and Technology of Production Systems and the Professional Master’s Program in Management and Development of Vocational Education.

    She is a member of the research groups on Information Systems and Digital Technologies, and Production and Operations Management within the Professional Master’s Program in Management and Technology of Production Systems. She also coordinates the Research Group on Management, Evaluation, and Organization of Vocational Education in the Professional Master’s Program in Management and Development of Vocational Education.

    She previously served as Vice Director, Academic Director of Faculdades e CET Radial, and later as Rector of its successor, Centro Universitário Radial. She has taught at several institutions, including FATEC-SP, UNICID, FECAP, UNISANTANA, FMU, and UniNove. Her research focuses on Quality Management; Strategic IT Management; and the Management, Evaluation, and Organization of Vocational Education.

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Published
2025-06-07
Issue
Vol. 11 No. 2 (2025): Regular Issue (April - June)
Section
OPERATIONS & PRODUCTION PROCESS
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Copyright (c) 2025 Thiago Loretti Arico Martins, Marilia Macorin de Azevedo (Autor)

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How to Cite

Martins, T. L. A., & Azevedo, M. M. de. (2025). Resources for the evaluation of the effectiveness of a Kaizen program aimed at reducing Lead Time. Brazilian Journal of Production Engineering, 11(2), 277-291. https://doi.org/10.47456/bjpe.v11i2.48071