This study evaluates post-discharge oral nutritional supplementation for patients with gastric cancer following gastrectomy. The evidence suggests that supplementation may mitigate postoperative weight loss during early-to-intermediate recovery, particularly after total gastrectomy, without an apparent increase in adverse events; however, effects on body composition, handgrip strength, laboratory markers, and durable long-term outcomes remain uncertain.
Research Article
Effect of Post-Discharge Oral Nutritional Supplements on Nutritional Status in Patients after Gastrectomy: A Systematic Review and Meta-Analysis
In This Article
Summary
Abstract
Nutritional intervention after gastrectomy is central to postoperative recovery, but the optimal outpatient supplementation strategy remains uncertain. This systematic review assessed the efficacy and safety of oral nutritional supplementation (ONS) after hospital discharge in patients undergoing gastrectomy for gastric cancer. Eligible randomized controlled trials (RCTs) were identified from five databases through September 2025. Extracted outcomes included adverse events, laboratory indices, body composition, handgrip strength, and body-weight change. Seven RCTs involving 1,736 participants met the review criteria, although the number of trials contributing to each pooled outcome varied. ONS significantly attenuated absolute body-weight loss (WMD: 0.75 kg; 95% CI: 0.11 to 1.40) and percentage body-weight loss (WMD: 1.42; 95% CI: 0.78 to 2.07) compared with control care. Risk-of-bias assessment identified generally adequate randomization and allocation reporting in most trials, but certainty remains limited by the small number of trials, substantial heterogeneity in the primary weight outcome, and the absence of a formal GRADE assessment. No significant inter-group differences were found for body composition, handgrip strength, or laboratory markers. Adverse-event incidence was not significantly different between groups when analyzed with the fixed-effect model selected for minimal heterogeneity (RR: 1.17; 95% CI: 0.92 to 1.49). These findings suggest that post-discharge ONS may help reduce early to intermediate postoperative weight loss after gastrectomy without a clear safety penalty. Because most endpoints were assessed between 8 weeks and 3 months, the durability of benefit beyond this period remains unclear.
Introduction
Gastric cancer remains a substantial global health burden and an important cause of cancer-related mortality. According to GLOBOCAN 2022 estimates, gastric cancer continues to rank among the leading causes of cancer incidence and death worldwide1. Although chemotherapy, targeted therapy, and immunotherapy have improved, gastrectomy remains a main curative option for locally advanced proximal tumors, diffuse-type disease, and selected other gastric cancers. It is also used prophylactically to reduce cancer risk in individuals carrying CDH1 mutations2. However, removal of all or part of the stomach changes gastrointestinal anatomy and may impair digestion and intake, leading to persistent postoperative issues such as weight loss, dumping symptoms, digestive discomfort, and malnutrition3.
Persistent malnutrition after gastric cancer surgery is associated with poorer overall and disease-free survival, impaired quality of life, higher postoperative complication risk, longer hospitalization, and reduced tolerance of adjuvant therapies4. Early, proactive, and structured nutritional intervention is therefore an important component of postoperative recovery planning5.
ONS is one outpatient option within a broader nutritional-care pathway that may also include individualized dietary counseling, symptom-directed meal modification, enteral tube feeding, or parenteral nutrition when oral intake is inadequate. Compared with tube-based or parenteral approaches, ONS is less invasive and easier to continue after discharge, but its effectiveness depends heavily on tolerance, palatability, dose, and adherence. Existing guidance and perioperative nutrition literature support ONS as a practical first-line oral strategy when patients cannot meet energy or protein needs through diet alone6,7,8,9. Accordingly, ONS should be viewed as a targeted and individualized component of postoperative nutritional support rather than a universally optimal intervention.
Clinical studies and systematic reviews have evaluated ONS use after gastrectomy, but findings remain inconsistent. Adherence is difficult after gastric surgery because nausea, early satiety, dumping symptoms, altered taste, and fatigue can limit daily intake. ONS formulations also differ in caloric density, protein content, and specialized ingredients, which makes direct comparison across trials challenging. In addition, many studies emphasize short follow-up windows, while outcomes that matter for sustained recovery, such as sarcopenia, handgrip strength, body composition, and quality of life, are reported less consistently. These limitations mean that current evidence supports possible post-discharge weight-maintenance benefit but does not yet establish durable long-term recovery or functional benefit10,11.
Several recent meta-analyses have evaluated ONS after gastrectomy or related gastrointestinal surgery12,13,14,15,16. However, prior syntheses vary in population scope, timing of supplementation, and outcome grouping. Some combine perioperative and post-discharge supplementation or include broader gastrointestinal or solid-tumor surgery populations, while fewer analyses explicitly separate follow-up duration, gastrectomy extent, safety, and feasibility after discharge. This review, therefore, focuses on post-discharge ONS in patients after gastrectomy for gastric cancer and interprets efficacy by outcome type, follow-up window, surgical anatomy, and safety profile.
Protocol
This systematic review and meta-analysis used only previously published aggregate data and did not involve direct contact with human participants or access to identifiable patient-level information. Institutional review board approval and informed consent were therefore not required. The software and databases used are listed in the Table of Materials.
Registration and search strategy
The review followed the PRISMA 2020 reporting framework during the planning, conduct, and reporting stages, and the preregistered PROSPERO protocol (CRD420251245644) was used to guide the eligibility criteria, outcomes, and analyses17.
PubMed, the Cochrane Library, Embase, Web of Science, and the China National Knowledge Infrastructure were searched from database inception through September 2025. Controlled vocabulary and free-text terms for “gastric neoplasms,” “gastrectomy,” “oral nutritional supplements,” and “ONS” were combined. All retrieved records were exported into a reference management file, duplicate records were removed, and the complete PubMed search strategy is documented in Supplementary Table 1.
Selection criteria
The PICOS framework was applied to determine study eligibility. The population was defined as adults who had undergone curative total, distal, partial, or proximal gastrectomy for gastric cancer. The intervention was defined as ONS initiated or continued after hospital discharge for at least 1 month. Follow-up periods were classified as early post-discharge (<3 months, including 8-week endpoints) or intermediate/longer follow-up (≥3 months) to avoid overinterpreting short-term endpoints as durable long-term outcomes. Control groups were defined as patients who received standard postoperative dietary management, dietary counselling alone, or no ONS. Eligible outcomes included body mass index, absolute and percentage body weight change, handgrip strength, body composition, serum biomarkers, and adverse events. Randomized controlled trials (RCTs) that reported sufficient information to calculate risk ratios, standardized mean differences, or weighted mean differences were included.
Studies with ineligible designs, including case reports, uncontrolled case series, reviews, meta-analyses, commentaries, conference abstracts, animal studies, and in vitro studies, were excluded. Studies involving populations without gastric cancer or gastrectomy, interventions limited to perioperative or in-hospital supplementation only, follow-up periods shorter than 1 month, or duplicate publications from the same study cohort were also excluded. Trials conducted in the context of adjuvant chemotherapy or mucositis prevention were included only if outcomes directly related to the safety or tolerability of post-gastrectomy ONS could be extracted. These trials were not considered primary evidence for postoperative nutritional efficacy unless nutritional outcomes were reported.
Data extraction and quality assessment
Titles and abstracts were screened independently against the PICOS criteria, and potentially eligible full-text articles were retrieved. Disagreements were resolved through discussion between the two authors. The reason for each full-text exclusion was recorded to enable reproduction of the PRISMA flow diagram.
Study characteristics, including the first author, publication year, region, study period, study design, and registration identifier, were extracted. Clinical details, including the type of gastrectomy, intervention and control protocols, ONS dose and duration, sample size, follow-up duration, age, sex, and baseline nutritional status, were also extracted. Outcome data, including absolute and percentage body weight change, body composition, handgrip strength, biochemical markers, and adverse events, were extracted using a standardized data extraction form.
When continuous variables were reported as medians with ranges or interquartile intervals, they were converted to means and standard deviations using the estimation methods described by Wan and Luo18,19. The risk of bias was assessed using the original Cochrane Risk of Bias tool (version 1.0) across the domains of random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessors, incomplete outcome data, selective reporting, and other sources of bias20. Domain-specific risk-of-bias judgments were reported rather than assigning an overall unsupported "moderate-to-high quality" rating.
Statistical analysis
Statistical analyses were conducted using R software (version 4.5.1) with the meta and metafor packages. Mean differences were calculated when outcomes were reported using the same measurement scale, whereas standardized mean differences were calculated when different scales were used. Risk ratios were calculated for dichotomous outcomes, such as adverse events. Forest plots with 95% confidence intervals (CIs) were generated, heterogeneity was assessed using the I2 statistic, and Cochran's Q test21, and a DerSimonian-Laird random-effects model was applied when I2 exceeded 50%, or the Q-test yielded p < 0.10. Otherwise, a fixed-effect model was used. Prespecified subgroup analyses were performed according to follow-up duration and gastrectomy type when sufficient data were available. Leave-one-study-out sensitivity analyses were conducted for primary outcomes with at least three contributing studies. Meta-regression and Egger's or Begg's tests were not performed when fewer than 10 studies were available because these analyses are underpowered and unreliable under such conditions22.
Results
Search results and patient characteristics
Figure 1 presents the PRISMA 2020 screening workflow. Database searches identified 214 records (PubMed, n = 53; Web of Science, n = 64; Embase, n = 47; Cochrane Library, n = 27; China National Knowledge Infrastructure, n = 23). No register or other-source records were identified. After 65 duplicate records were removed, 149 records were screened. Seventy-nine records were excluded during title and abstract screening, leaving 70 reports for full-text assessment. Sixty-three reports were excluded for specific reasons (with respective counts detailed in Figure 1), leaving seven RCTs for final inclusion in the systematic review.
Seven studies were included, encompassing 1,736 participants with gastric cancer after gastrectomy6,23,24,25,26,27,28. The number of trials contributing to each quantitative synthesis varied by outcome availability. Six trials informed nutritional efficacy outcomes, while the Toyomasu study was retained only for safety/tolerability interpretation because its intervention was delivered in the adjuvant chemotherapy/oral mucositis context. Two trials reported multiple gastrectomy strata, which allowed subgroup interpretation by surgical anatomy. Key characteristics, including analytic role, lead author, publication year, registration identifier, trial period, surgical procedure, intervention, and sample size, are summarized in Table 1.
Risk of bias
The Cochrane Risk of Bias assessment showed that most included trials reported adequate random sequence generation and allocation concealment, and no clear selective-reporting concern was identified across the included cohort. However, blinding procedures and incomplete outcome data varied by study, and the small number of trials limits confidence in any overall study-level quality classification. Therefore, the risk-of-bias findings are reported by domain rather than summarized as a single moderate-to-high quality rating (Figure 2).
Absolute change of body weight
A pooled analysis of four RCTs6,23,24,25 involving 1,564 patients (ONS: n = 793; control: n = 771) found that ONS was associated with significantly less absolute body-weight loss than routine care (WMD: 0.75 kg; 95% CI: 0.11 to 1.40). Heterogeneity was substantial (I2 = 87%); however, the leave-one-study-out sensitivity analysis (Supplementary Table 2) revealed that omitting the Miyazaki trial collapsed the I2 from 87% to 0%, indicating that this single trial drove all of the observed statistical heterogeneity. In the >=3-month subgroup, the point estimate favored ONS but did not reach statistical significance (WMD: 0.66 kg; 95% CI: -0.06 to 1.38). The <3-month subgroup was represented by only one trial and showed a significant effect (WMD: 1.18 kg; 95% CI: 0.07 to 2.29), so this finding should be interpreted as single-study evidence rather than a robust subgroup effect (Figure 3).
Percentage change of body weight
A pooled analysis of five RCTs involving 1,182 patients (ONS: n = 598; control: n = 584) evaluated percentage body-weight change23,25,27,28. ONS significantly attenuated postoperative percentage weight loss compared with control care (WMD: 1.42; 95% CI: 0.78 to 2.07). In subgroup analysis, the total-gastrectomy subgroup showed a significant reduction in percentage weight loss (WMD: 2.42; 95% CI: 0.41 to 4.43), whereas the distal-gastrectomy subgroup did not reach statistical significance (WMD: 0.71; 95% CI: -0.40 to 1.81) (Figure 4).
Absolute change of body composition
Only one eligible study reported absolute changes in body composition, including fat mass and skeletal muscle mass; therefore, a pooled quantitative analysis was not possible. In that study23, no statistically significant between-group differences were observed in the distal-gastrectomy subgroup for fat mass (WMD: 0.11 kg; 95% CI: -1.07 to 1.24; p = 0.85) or skeletal muscle mass (WMD: -0.21 kg; 95% CI: -0.71 to 0.34; p = 0.46). Similar nonsignificant results were observed in the total-gastrectomy subgroup for fat mass (WMD: -0.31 kg; 95% CI: -1.88 to 1.30; p = 0.71) and skeletal muscle mass (WMD: 0.59 kg; 95% CI: -0.47 to 1.70; p = 0.28). These single-study findings do not support a clear effect of ONS on body composition.
Absolute change of laboratory parameters
Two RCTs6,28 examined absolute changes in laboratory indicators. A pooled analysis of both trials revealed no statistically significant difference in hemoglobin levels (WMD: -0.23; 95% CI: -0.86 to 0.39). Data for the remaining indicators were extractable from only one trial6, which similarly reported no significant between-group differences for albumin (WMD: 0.03; 95% CI: -0.15 to 0.21), total protein (WMD: 0.11; 95% CI: -0.17 to 0.44; p = 0.44), or total cholesterol (WMD: 5.37; 95% CI: -6.51 to 17.23; p = 0.37) (Figure 5).
Absolute change in handgrip strength
Only one RCT assessed handgrip strength, preventing pooled analysis28. No significant between-group difference was observed for absolute handgrip strength (WMD: -0.91; 95% CI: -3.91 to 2.22; p = 0.56) or percentage change (WMD: -0.68; 95% CI: -4.10 to 2.56; p = 0.67). A subgroup of patients with lower baseline grip strength appeared to have a numerically greater preservation effect, but this result was not statistically significant (WMD: 8.81; 95% CI: -4.92 to 22.51; p = 0.19) and should be considered hypothesis-generating only.
Adverse events
Five trials involving 1,286 participants reported adverse-event outcomes6,25,26,27,28. Reported events were generally non-serious and included gastrointestinal symptoms or treatment-context events where specified; the Toyomasu study specifically contributed safety information from an adjuvant chemotherapy/oral mucositis setting. The fixed-effect model was selected because heterogeneity was minimal (I2 = 0%; p = 0.40), and it showed no statistically significant difference between the ONS and control groups (RR: 1.17; 95% CI: 0.92 to 1.49; p = 0.21). A post hoc sensitivity check excluding Toyomasu remained nonsignificant (RR: 1.22; 95% CI: 0.94 to 1.57), supporting the conclusion that no clear adverse-event increase was detected (Figure 6; Supplementary Table 2).
Publication bias
Publication bias was assessed visually with funnel plots for absolute body-weight change, percentage body-weight change, laboratory markers, and adverse events (Figure 7A–D). Because each analysis contained fewer than 10 studies, funnel-plot interpretation was considered exploratory, and formal Egger or Begg tests were not performed. Therefore, the absence of obvious visual asymmetry should not be interpreted as definitive evidence that publication bias is absent.
DATA AVAILABILITY:
All data analyzed in this systematic review and meta-analysis were derived from previously published studies. No new patient-level data were generated for this study.
Figure 1: PRISMA 2020 flow diagram of record identification, screening, report eligibility assessment, and study inclusion. The diagram separates database/register records from other sources and reports the final inclusion of seven randomized controlled trials. Please click here to view a larger version of this figure.
Figure 2: Risk of bias assessment for the included studies. The upper panel displays a study-by-study summary of specific bias domains, while the lower panel aggregates the overall risk percentage across all evaluated methodological criteria using the Cochrane framework. Please click here to view a larger version of this figure.
Figure 3: Forest plot detailing absolute weight change. This analytical synthesis compares mean differences in absolute body weight loss between intervention and control cohorts, stratified specifically by follow-up duration. Please click here to view a larger version of this figure.
Figure 4: Forest plot depicting percentage weight change. The graphic illustrates the relative reduction in body weight, effectively stratifying the pooled results according to the anatomical extent of the gastrectomy. Please click here to view a larger version of this figure.
Figure 5: Forest plot summarizing absolute changes in laboratory parameters. This quantitative synthesis evaluates specific postoperative fluctuations in essential biochemical markers, specifically focusing on serum albumin and hemoglobin levels. Please click here to view a larger version of this figure.
Figure 6: Forest plot analyzing the incidence of adverse events. The chart delineates the relative risk of experiencing postoperative complications, displaying both fixed-effect and random-effects statistical models. Please click here to view a larger version of this figure.
Figure 7: Funnel plots assessing potential publication bias. These scatter plots visually map standard error against effect size for absolute weight change (A), percentage weight change (B), laboratory parameters (C), and adverse events (D). Please click here to view a larger version of this figure.
Table 1: Characteristics and analytic role of included studies. Abbreviations: DG, distal gastrectomy; TG, total gastrectomy; PG, proximal gastrectomy; NA, not available; ONS, oral nutritional supplements. Please click here to download this Table.
Supplementary Table 1: PubMed search strategy. The detailed PubMed search process is shown as an example of the database retrieval strategy. Please click here to download this file.
Supplementary Table 2: Sensitivity analysis. The leave-one-study-out analysis for absolute body-weight change and the post hoc Toyomasu-exclusion analysis for adverse events are shown as sensitivity checks for study influence and indirectness. Please click here to download this file.
Discussion
Gastrectomy remains a major curative treatment for localized gastric cancer and has important implications for postoperative recovery and prognosis29. Reduced gastric capacity, altered gastrointestinal motility, impaired nutrient absorption, and surgical stress can lead to inadequate energy intake, weight loss, and deterioration in nutritional status30,31. These changes may affect postoperative complications, chemotherapy tolerance, treatment adherence, quality of life, and survival. Therefore, nutritional support after discharge is clinically relevant, particularly during the early recovery window when oral intake is limited, and weight loss can be rapid.
This synthesis suggests that post-discharge ONS can reduce absolute and percentage body-weight loss compared with routine dietary management. However, the benefit was most consistent for weight-related outcomes, while body composition, handgrip strength, and laboratory markers did not show clear improvement. The safety synthesis did not identify a significant increase in adverse events. These findings support ONS as a practical adjunct to structured dietary care after gastrectomy, but the conclusions should remain cautious because the primary weight outcome showed substantial heterogeneity, and several secondary outcomes were informed by only one or two studies.
The time course of benefit requires careful interpretation. Most included endpoints were measured at 8 weeks or 3 months, so the evidence is better described as early to intermediate post-discharge rather than truly long-term. In the absolute body-weight analysis, the >=3-month subgroup favored ONS but was not statistically significant, while the <3-month subgroup came from a single trial. This pattern suggests that ONS may be most useful when postoperative intake is most constrained, but it does not prove a durable effect beyond the initial recovery period. A longer follow-up with consistent adherence measurement is needed before strong conclusions can be drawn.
From a practical standpoint, the included trials utilized outpatient regimens, such as elemental or polymeric formulas providing approximately 400 kcal/day, which deliver concentrated energy and protein in a relatively low volume. These regimens are particularly applicable to patients who cannot meet nutritional requirements through diet alone, especially following total gastrectomy, where reduced reservoir capacity and altered emptying intensify early satiety. Compared with enteral tube feeding or parenteral nutrition, ONS is less invasive and more compatible with outpatient self-management. However, it is not a substitute for individualized dietary counseling, and its effectiveness remains highly vulnerable to poor adherence. Common barriers include gastrointestinal intolerance, taste fatigue, and psychological burden10,11. Consequently, formulation choice must account for patient preference and tolerability, and future trials should rigorously measure actual intake and symptom burden rather than assuming prescribed supplementation equals consumed supplementation.
To ensure the robustness of the findings, several critical procedural steps and methodological adaptations were explicitly incorporated into the review design to guarantee successful execution. The strict adherence to the preregistered PROSPERO protocol and PRISMA guidelines minimized selection and reporting biases32. Furthermore, when encountering common meta-analytical challenges, such as the substantial statistical heterogeneity observed in the primary body-weight analysis, we implemented specific troubleshooting strategies. By utilizing a leave-one-study-out sensitivity analysis, we successfully pinpointed the source of the substantial heterogeneity in the primary absolute body-weight analysis. Specifically, omitting the Miyazaki trial collapsed the I2 from 87% to 0%. This indicates that the Miyazaki trial essentially drove all of the statistical heterogeneity, a finding that may be attributable to its robust phase 3 multicenter design, specific nutritional formulation, or distinct trial scale relative to the other included studies. Although the pooled estimates remained directionally consistent across all omission scenarios, explicitly identifying this primary driver clarifies that the observed variance is not a systemic flaw within the evidence base, but rather a direct reflection of this single trial's distinct methodological footprint and outsized statistical influence. Similarly, to address the clinical indirectness of trials conducted within an adjuvant chemotherapy context (such as the Toyomasu study), our methodological adaptation was to isolate this evidence solely for safety and tolerability endpoints, followed by a post hoc exclusion sensitivity check. This explicit protocol design and our adaptive analytical troubleshooting directly support our conclusions, ensuring that the observed early benefits of ONS are grounded in rigorous evidence synthesis rather than outlier effects.
Despite these methodological safeguards, this review retains several inherent limitations. First, the number of eligible RCTs was small, and some outcomes were based on one or two studies, which inherently limits statistical precision. Second, although our sensitivity analyses addressed the substantial heterogeneity in the primary absolute body-weight outcome, this heterogeneity indicates that the true effect size may still vary across different clinical or surgical settings. Third, the included trials differed intrinsically in ONS formulation, caloric density, protein content, follow-up duration, and surgical anatomy, which precluded more granular subgroup analyses. Finally, because a formal GRADE certainty-of-evidence assessment was not performed, the small overall evidence base and persistent clinical heterogeneity mean that certainty in the pooled estimates should be considered limited33,34.
The findings should also be interpreted in relation to recently published work. The identical 0.75 kg WMD for absolute body-weight change is expected because the present review and the Liang meta-analysis drew on the same core RCTs for that endpoint13. Choi et al. similarly concluded that ONS can reduce body-weight loss after gastrectomy, but the present review adds clearer separation of post-discharge timing, percentage weight loss, surgical anatomy, safety, and methodological limitations12. Liu et al. synthesized postoperative ONS across solid tumors, and Rowley et al. evaluated gastrointestinal surgery more broadly; those reviews support the plausibility of ONS benefit but are less specific to gastrectomy after gastric cancer14,35. Omori et al. provided important trial-level long-term follow-up evidence, complementary to this, our synthesis integrates the available randomized post-discharge data to clarify the magnitude of benefit specifically during the early to intermediate recovery phase15.
Overall, post-discharge ONS should be considered for patients at high risk of early postoperative weight loss, especially after total gastrectomy or when routine intake is insufficient. Future RCTs should compare ONS with structured dietary counseling and other nutritional routes, standardize dose and duration, report adherence and adverse-event types, include body-composition and functional outcomes, and extend follow-up beyond 6–12 months.
Disclosures
The authors have nothing to disclose.
Acknowledgements
Gratitude is expressed to colleagues at Xi'an Jiaotong University and Fudan University for general support and valuable suggestions during manuscript preparation. Appreciation is also extended to the reviewers and editors for constructive comments that significantly improved the quality of this work. The authors declare that no specific grant was received from any funding agency in the public, commercial, or not-for-profit sectors.
Materials
| Name | Company | Catalog Number | Comments |
|---|---|---|---|
| China National Knowledge Infrastructure (CNKI) | CNKI | https://www.cnki.net/ | Chinese-language literature database searched for eligible records |
| Cochrane Library | Cochrane / Wiley | https://www.cochranelibrary.com/ | Systematic review and clinical trial database searched for eligible records |
| Cochrane Risk of Bias framework | Cochrane Methods | https://methods.cochrane.org/bias/ | Domain-level risk-of-bias assessment for randomized controlled trials |
| Embase | Elsevier | https://www.embase.com/ | Biomedical and pharmacological literature database searched for eligible records |
| EndNote | Clarivate | Version 21; https://endnote.com/ | Reference management and citation formatting |
| GRADE approach | GRADE Working Group | https://www.gradeworkinggroup.org/ | Certainty-of-evidence framework discussed in the limitations |
| PRISMA 2020 reporting guideline | PRISMA Statement | https://www.prisma-statement.org/ | Reporting framework for the systematic review and PRISMA flow diagram |
| PROSPERO registry | Centre for Reviews and Dissemination, University of York | CRD420251245644; https://www.crd.york.ac.uk/prospero/ | Prospective registration record for the systematic review protocol |
| PubMed | National Library of Medicine / NCBI | https://pubmed.ncbi.nlm.nih.gov/ | Biomedical literature database searched for eligible trials |
| R package: meta | CRAN / R package authors | https://cran.r-project.org/package=meta | Meta-analysis functions for pooled effect estimates and forest plots |
| R package: metafor | CRAN / Wolfgang Viechtbauer | https://cran.r-project.org/package=metafor | Supplementary meta-analysis calculations and heterogeneity checks |
| R software | R Foundation for Statistical Computing | Version 4.5.1; https://www.r-project.org/ | Statistical environment for meta-analysis and sensitivity checks |
| Web of Science | Clarivate | https://www.webofscience.com/ | Citation and multidisciplinary literature database searched for eligible records |
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