A Primer of Data Cleaning in Quantitative Research: Handling Missing Values and Outliers

Amir Masoud Sharifnia; Daniel Edem Kpormegbey; Deependra Kaji Thapa; Michelle Cleary

doi:10.1111/jan.16908

A Primer of Data Cleaning in Quantitative Research: Handling Missing Values and Outliers

J Adv Nurs. 2025 Mar 27. doi: 10.1111/jan.16908. Online ahead of print.

Authors

Amir Masoud Sharifnia¹, Daniel Edem Kpormegbey², Deependra Kaji Thapa^{2

3}, Michelle Cleary³

Affiliations

¹ Student Research Committee, Khomein University of Medical Sciences, Khomein, Iran.
² Department of Epidemiology and Biostatistics, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana, USA.
³ School of Nursing, Midwifery and Social Sciences, Central Queensland University, Sydney, New South Wales, Australia.

PMID: 40145308
DOI: 10.1111/jan.16908

Abstract

Aims: This paper discusses data errors and offers guidance on data cleaning techniques, with a particular focus on handling missing values and outliers in quantitative datasets.

Design and methods: Methodological discussion.

Results: This paper provides an overview of various techniques for identifying and addressing data anomalies, which can arise from incomplete, noisy, and inconsistent data. These anomalies can significantly affect data quality, leading to biased model parameter estimates and evidence-based decisions. Data cleaning, particularly the appropriate handling of missing values and outliers, is essential to improving data quality before analysis. Data cleaning includes screening for anomalies, diagnosing errors, and applying appropriate corrective measures.

Conclusion: Proper handling of missing values and the identification and correction of outliers are crucial aspects of data cleaning in ensuring data quality and the reliability of statistical analyses. Effective data cleaning enhances the validity and accuracy of research findings for evidence-based decision making that leads to optimal patient outcomes.

Implications for the profession: The quality of study results depends on how a dataset and its complexities are processed or handled before the analysis. Nursing researchers must use a framework to identify and address important data anomalies and produce reliable results.

Impact: This paper describes data cleaning, often overlooked during the data mining process, as a crucial step before conducting data analysis. By addressing missing values and outliers, identifying and fixing data anomalies, and enhancing data quality prior to analysis, data cleaning techniques can produce precise research findings for evidence-based decision making.

Reporting method: In this methodological paper, no new data were generated.

Patient or public contribution: No patient or public contribution.

Keywords: data cleaning; data preparation; inconsistent values; missing values; outliers; quantitative research.