d at least 18 years. Second, the study had to include data assessing AKI incidence or mortality risk with 95% confidence intervals (CIs) (or sufficient raw data for the calculation). Patients were excluded if they only used a temporary, short-term, non-implantable LVAD during a hospitalization. Study eligibility was independently determined by two investigators (CT and PL). Differences were resolved by mutual consensus.

A standardized data collection form was used to obtain the following information from each study: title, name of the first author, year of study, year of publication, country of origin, number of participants, demographic data of participants, the method used to diagnose the outcomes of interest (AKI incidence and associated mortality), the average duration of follow-up, adjusted and unadjusted risk ratios and their corresponding 95% CI, and list of confounders that were adjusted for in the multivariate analyses. To ensure accuracy, both investigators independently performed this data extraction process. Any data discrepancy was resolved by referring back to the original articles. The Newcastle-Ottawa quality assessment scale was utilized to appraise the quality of observational studies \[[@CIT0072]\].

Statistical analysis {#s0005}
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The meta-analysis of combined data was performed using a random-effects, generic inverse variance method of DerSimonian and Laird \[[@CIT0073]\]. We assessed the overall incidence of AKI, which was defined by the consensus definitions provided by the Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) \[[@CIT0074]\], Acute Kidney Injury Network (AKIN) \[[@CIT0075]\], and Kidney Disease: Improving Global Outcomes) (KDIGO) \[[@CIT0076]\] classifications. We did not impute missing values for any outcomes in our analyses. A random-effect model was used to pool AKI incidence and AKI-associated mortality risk due to the possibility of between-study variance. Heterogeneity among included studies was statistically evalu