Exploration of Medicine

Table 3. Pearson correlation matrix (pooled, n = 24).

Variable	DALYs_rate	Deaths_rate	Incidence_rate	Prevalence_rate	YLDs_rate	YLLs_rate	Nitrogen	Nitrate	Temperature	DO	CCME
DALYs_rate	1.000^**	0.351	–0.897	–0.330	0.958	0.997	–0.940	–0.196	0.908	–0.174	–0.188
Deaths_rate	0.351	1.000^**	–0.427	–0.708	0.228	0.379	–0.400	0.472	–0.028	0.688	–0.496
Incidence_rate	–0.897	–0.427	1.000^**	0.666	–0.952	–0.869	0.976	–0.130	–0.751	–0.114	0.355
Prevalence_rate	–0.330	–0.708	0.666	1.000^**	–0.411	–0.303	0.557	–0.687	–0.025	–0.739	0.565
YLDs_rate	0.958	0.228	–0.952	–0.411	1.000^**	0.932	–0.973	–0.136	0.913	–0.159	–0.214
YLLs_rate	0.997	0.379	–0.869	–0.303	0.932	1.000^**	–0.917	–0.210	0.893	–0.176	–0.177
Nitrogen	–0.940	–0.400	0.976	0.557	–0.973	–0.917	1.000^**	–0.008	–0.826	–0.022	0.347
Nitrate	–0.196	0.472	–0.130	–0.687	–0.136	–0.210	–0.008	1.000^**	–0.495	0.721	–0.387
Temperature	0.908	–0.028	–0.751	–0.025	0.913	0.893	–0.826	–0.495	1.000^**	–0.493	0.017
DO	–0.174	0.688	–0.114	–0.739	–0.159	–0.176	–0.022	0.721	–0.493	1.000^**	–0.486
CCME	–0.188	–0.496	0.355	0.565	–0.214	–0.177	0.347	–0.387	0.017	–0.486	1.000^**

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^** P < 0.01. Pooled correlations reflect between-country differences and do not imply causation. DO: dissolved oxygen.

Declarations

Author contributions

TR: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Visualization, Writing—original draft, Writing—review & editing. ZZ: Conceptualization, Investigation, Methodology, Validation, Writing—review & editing. TR and ZZ contributed equally to this work. Both authors read and approved the submitted version.

Conflicts of interest

The authors declare that there are no conflicts of interest.

Ethical approval

This study used publicly available, de-identified aggregate data. No ethical review was required.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

The CKD burden data analyzed in this study were obtained from the Institute for Health Metrics and Evaluation (IHME) GBD Results Tool (https://vizhub.healthdata.org/gbd-results/), subject to IHME data-use terms. The downloaded IHME citation identified the release as Global Burden of Disease Study 2023 (GBD 2023) Results, and the present analysis was restricted to country-year estimates from 2010 to 2017. Water quality data were obtained from public monitoring sources in China, Canada, and Ireland, as documented in the source file. Derived datasets and analysis code are available from the corresponding author upon reasonable request.

Funding

This work was supported by the Yunnan Provincial Department of Education Science Research Fund (grant numbers 2026J2256 and 2024J2133). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright

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