The REIN figures were extracted from the Excel table

For comparable dates, the RDPLF contains between 90% and 97% of the patients recorded in the REIN database (Figure 2); the number of incident patients during the same years is slightly higher in the RDPLF, ranging from 114% to 123% (Figure 3). Despite these differences, the trends are similar.

The REIN data are extracted from Table 3-15 of the report; the RDPLF figures represent patients who had not undergone any other renal replacement therapy prior to starting PD. The number of patients is 963 in the RDPLF and 965 in REIN, representing 94% of REIN patients registered in the RDPLF; at the regional level, three regions have less than 90% of patients included in REIN, and two regions have more than 100% of REIN patients registered in the RDPLF (Table I).

The peritoneal dialysis techniques used by patients as of December 31, 2024, by age were reproduced from Figure 4-6 of the REIN report. The figures obtained from the RDPLF database for the same period are very close to, or even identical to, those of the REIN registry (Figure 4).

Data from the REIN registry are obtained from Table 4-16 of the REIN report. The number of patients reported in the RDPLF is higher than in the REIN registry for these items, but the percentages are virtually identical in both registries. The few differences can be explained by a higher percentage of unspecified assistance types in the REIN registry (Table II).

Table II. Percentages of patients treated with APD or CAPD and percentages by degree of autonomy and assistance, in the REIN registry and the RDPLF.

The RDPLF anemia module is optional; thus, in 2014, it covered only 23 of the 151 RDPLF centers, and 115 of the 1,206 patients—just under 10%—had data recorded at the start of treatment.

According to figure 3-6 of the REIN report, at the start of PD treatment:

- 75% of patients had Hb ≥ 10 g/L.

- 16% of patients had Hb < 10 g/L while taking erythropoiesis-stimulating agents (ESAs).

- 10% of patients had Hb < 10 g/L without ESAs.

However, this data was actually obtained from the optional module of the RDPLF, so it cannot be compared with a comprehensive national survey.

According to Table 4-6 of the REIN report, hemodialysis modality was reported for 38,673 patients: 1.7% of them, or 657, were treated with home hemodialysis (HHD). As of the same date, 313 patients were receiving HD at home in the RDPLF database, representing 47% of patients included in the REIN registry.

The data presented in the REIN report regarding HHD differ from those in the RDPLF or are grouped with other forms of self-administered dialysis. It is not possible to use this method to compare the two databases on other items. The number of sessions per week, for example, is available in the RDPLF but is not included in the report.

DISCUSSION

In 2006, we collaborated with the REIN registry to assess the quality of the information and the concordance of shared data.

Good overall concordance between REIN and the RDPLF for common data was demonstrated in a previous article published in 2006 ³. That study highlighted the reliability and representativeness of both registries and the synergy of their activities in monitoring PD treatments. Twenty years later, we felt it was useful to verify the concordance of the main common information recorded in both registries. The operating procedures and objectives of the two registries remain very different (Table III).

Cross-referencing complementary registries such as the RDPLF and REIN is recommended to enrich the analyses and improve their robustness, provided that regulatory and methodological requirements related to data matching are met; this would require a common patient identifier, which raises ethical issues that are difficult to resolve as of today. The 2006 article ³ demonstrated excellent concordance in biological and anthropometric data values for patients common to both databases. The present study is not based on a cross-referencing of the two databases; no physical or software link exists between the two registries. The publication of the REIN report thus allows for, completely independently of the two systems, a comparison of the completeness of patient coverage. As of a fixed date, the completeness of prevalent patients is always greater than 90% of the number of patients included in REIN; on an annual basis, the completeness is always higher than that of REIN. These apparent differences are easily explained by the updating procedures: In REIN, each patient is updated annually, whereas in the RDPLF, centers update all their patients in real time or nearly so as changes occur. The number of patients at a given time or period is therefore not up to date at the same time in both registries. Nevertheless, these differences are negligible, as shown by the analysis of the results that are consistent with the report: The distribution of techniques and modes of assistance are similar, for example.

The fact that the RDPLF’s optional modules are not exhaustive could reduce their representativeness but can supplement certain missing data in the REIN report: for example, information on haemoglobin levels and the use of ASE was obtained from the anaemia module of the RDPLF. For the centres that use them, the optional modules are primarily a means of monitoring their clinical practice; however, they can also provide a national overview of data not included in the REIN report. It may be possible to compare other biological, clinical or anthropometric values by using information not included in the report.

As with PD, HD is documented in greater detail in the RDPLF; thus, the duration of home sessions, complications related to vascular access, the percentage of return visits to the center, transfers between home dialysis techniques, etc., are recorded ⁴. The REIN report we used as a reference did not include the same data as those available in the RDPLF, and only the number of patients included could be assessed: Only 47% of HDD patients recorded in REIN are in the RDPLF; it will be useful in the future to attempt to compare variables common to both registries. National participation by HDD units is more difficult to achieve than for PD, likely for various reasons: lack of time on the part of the teams and lack of motivation. This difference is indirectly confirmed by the number of publications in the Bulletin de la Dialyse à Domicile, in which the number of submissions on HDD is significantly lower than those on PD.

At a time when policymakers and doctors are seeking to promote home dialysis, the RDPLF is undoubtedly one of the strongest advocates for this approach: Not only does it maintain a reliable, specialized database on home care, but it also provides direct support to teams by offering them direct access to basic statistics generated from the database, mailing lists reserved for nurses and doctors alike, a protocol server, and a free, open-access bilingual journal for both authors and readers. This is made possible thanks to the work of the nurses and doctors who regularly update their data and the authors who share their knowledge and experience in the database (https://bdd.rdplf.org).

The weakness of this study lies in the small number of variables common to both registries that could be compared. A more in-depth study would be useful and could be achieved by obtaining REIN data that are not included in its report but are identical to those in the RDPLF.

CONCLUSION

The RDPLF database has a coverage rate, in terms of the number of patients included, compared to the REIN registry, that exceeds 90% for prevalent patients and 100% for incident patients. As in the study conducted 20 years earlier ³, the two registries appear to be complementary and synergistic in promoting and advancing home dialysis techniques. We encourage French-speaking RDPLF member countries that have a national registry to also verify the consistency of data between their respective registries and the RDPLF.

Acknowledgments

We would like to thank the health-care teams and physicians who ensure the continuous entry of their patients’ data, for the quality and consistency of their work over the past 40 years, on behalf of the RDPLF.

Funding

The authors received no specific grants for this study from public, commercial, or nonprofit funding organizations.

Authors’ contributions

Emmanuel Fabre: Developed the database, contributed to the extraction of RDPLF data, and reviewed the article; Walid Arkouche, Jacques Chanliau, Max Dratwa, Belkacem Issad, Marie-Christine Padernoz, Ghislaine Veniez: Participate in the operation of the RDPLF, reviewed the article, and provided constructive feedback; Christian Verger: Conceived and wrote the article.

Ethical considerations

This study was conducted in accordance with the ethical principles of the Declaration of Helsinki.

Patient consent

Centers participating in the RDPLF provide patients included in the study with an informed consent form for inclusion in the database. All data are processed after complete anonymization.

Artificial intelligence

The authors declare that this manuscript is the result of their own original work. No artificial intelligence tools or applications were used for data analysis, generation of results, or the creation and drafting of the text.

Conflicts of interest

The authors declare that they have no conflicts of interest related to the writing of this text.

Data availability

The datasets generated and analyzed in this study are available from the author upon reasonable request.

How to cite

Fabre E, Arkouche W, Chanliau J, Dratwa M, Issad B, Padernoz M-C, Veniez G, Verger C. Assessment of the Completeness and Representativeness of the RDPLF Registry Using the French National REIN Registry as a Reference: Comparison with the REIN Registry’s 2026 report. Bull Dial Domic [Internet]. [cited 2026 Jun. 14];9(2):93-101. doi: https://doi.org/10.25796/bdd.v9i2.87114