Statistical methods for primary and secondary outcomes

SPSS 26.0 statistical software will be used to analyze the data. The count data will be expressed as numbers or percentages (%), and comparisons between groups will be performed via the chi2 test or Fisher’s exact test. The normally distributed measurement data will be represented as \(\overline }\) ± s, and the comparisons between groups will be performed by independent sample t-tests. The measurement data that are not normally distributed will be described by the mean (P25, P75), and the Wilcoxon rank sum test will be used for comparisons between groups. p < 0.05 will be considered to indicate statistical significance.

Interim analyses

Interim analysis will not be performed in this study.

Methods for additional analyses (e.g., subgroup analyses)

Additional analyses will not be performed. No subgroups will be set, and subgroup analyses will not performed in this study.

Methods in the analysis to handle protocol nonadherence and any statistical methods to handle missing data

Multiple imputation will be used to manage missing values.

Plans to give access to the full protocol, participant-level data, and statistical code

The data will be available upon reasonable request. For inquiries about data sharing, please send a request to liumingbjh@126.com.

Oversight and monitoring composition of the coordinating center and trial steering committee

The trial steering committee consists of four members, three senior urologists and a statistician who will oversee the trial. The committee is independent of the research team, and there are no conflicts of interest. The trial was designed by two senior urologists. A urologist will collect the clinical data.

Composition of the data monitoring committee, its role, and reporting structure

The data monitoring committee will provide regular oversight, hold monthly meetings, and organize site visits every 2 months to ensure smooth and ethical conduct of the trial. In addition, supervisors will ensure the authenticity and completeness of the data. During the visit, a committee member will interview investigators and review original study documents. Any noncompliance with the protocol will be fully documented via a violation report form.

Adverse event reporting and harms

Adverse events (AEs) refer to all adverse medical events that occur after a subject has received the study URS lithotripsy treatment; these events can manifest as symptoms and signs, diseases, or laboratory abnormalities but may not be causally related to the investigational drug.

Serious adverse events (SAEs) or reactions/experiences refer to medical events that occur during the clinical trial, such as hospitalization, prolonged hospitalization, disability, affected work ability, life-threatening events or death, or congenital malformation. AEs and laboratory tests will be graded according to the NCI-CTCAE, version 5.0. All AEs occurring within 30 days after the last procedure will be recorded. AEs are listed and summarized descriptively. Serious adverse events that persist after treatment, recovery to baseline status, steady state, or loss to follow-up will be recorded.

Common adverse reactions of ureteroscopic lithotripsy: The overall complication rate of ureteroscopic lithotripsy is only 3.5%, including ureteral perforation (0–4%), ureteral stricture (3–6%), submucosal stones and stone loss (2%), and ureteral avulsion (0.06–0.5%). Ureteral injury, hematuria, and infection are common complications, but most cases are mild and do not require special treatment.

All treatment-related AEs will be managed according to clinical practice.

Conditions that are present before the index treatment (e.g., elevated laboratory values) will not be reported as AEs. If the severity of an AE increases, the investigator must reassess the event to determine whether it must be reported.

Frequency and plans for auditing trial conduct

We will audit the trial conduct every 6 months.

Plans for communicating important protocol amendments to relevant parties (e.g., trial participants, ethical committees)

The committee will identify problems in the trial and recommend changes to the trial protocol. If a decision to modify the protocol is needed, a written request will be submitted to the Institutional Medical Ethics Committee, and after approval, the investigator will be notified in writing. The protocol will be updated in the system immediately.

Dissemination plans

Any data undermining blinding will not be released until the results are published. The main findings will be published in the article.