Can requests for real-world evidence by the French HTA body be planned? An exhaustive retrospective case-control study of medicinal products appraisals from 2016 to 2021.

OBJECTIVES: In France, decisions for pricing and reimbursement for medicinal products are based on appraisals performed by the National authority for health (Haute Autorité de Santé (HAS)). During the appraisal process, additional real-world evidence can be requested as "Post-Registration Studies" (PRS) when there are uncertainties in evidence that could be resolved by additional data collection. To facilitate PRS planning, a retrospective exploratory analysis was conducted to identify the characteristics of medicinal products associated with a PRS request. METHODS: This analysis encompassed all appraisals finalized between January 1, 2016 and December 31, 2021 and compared products for which the appraisal led to a PRS request with those that did not. RESULTS: Six hundred positive opinions for reimbursement were identified, with a PRS request present in 17 percent (n = 103) of cases. The independent characteristics associated with a PRS request were a mild or moderate clinical benefit score, a major to moderate or minor clinical added value score, previous availability under an early access program, and certain therapeutic areas (neurology, pulmonology, and endocrinology). These findings suggest two different profiles of PRS requests: (i) products for which there is uncertainty in the size of the clinical benefit and (ii) innovative products for which a substantial benefit is expected but uncertainties persist. CONCLUSIONS: These results will assist health technology developers to better anticipate data generation to promptly address uncertainties identified by HAS. It may also help HAS and other assessment agencies to work together to improve postlaunch evidence generation according to the characteristics of the medicinal products.

Parental mental health and reporting of their child's behaviour: measurement invariance of the French version of the parental strengths and difficulties questionnaire.

Symptomatic effects of mental disorders in parents could bias their reporting on their child's mental health. This study aimed to investigate the measurement invariance of the French version of the parental Strengths and Difficulties Questionnaire (SDQ) across parental mental health in a sample (N = 20,765) of parents of children aged 3 to 17 years in France. Confirmatory factor analysis (CFA) and Exploratory Structural Equation Modelling (ESEM) were used to evaluate the fit of three known alternative SDQ factor structures (five, three, or second-order factor structures). Invariance was tested across parental mental health (present anxiety and depressive symptoms, psychiatric history) and across socio-demographic characteristics (child's age, child's gender, parent's gender, parent's educational level). CFA models showed a poor fit, while all ESEM models achieved acceptable or good fit, with the five-factor model presenting the best fit. Invariance was observed for all characteristics tested, indicating that the SDQ can be used to study the links between parental mental health and their child's mental health without bias. However, ESEM showed that the hyperactivity/inattention and conduct problems dimensions were not well differentiated in the French version of the SDQ.

Implications of the syntheses on definition, theory, and methods conducted by the Response Shift - in Sync Working Group.

PURPOSE: Our aim is to advance response shift research by explicating the implications of published syntheses by the Response Shift - in Sync Working Group in an integrative way and suggesting ways for improving the quality of future response shift studies. METHODS: Members of the Working Group further discussed the syntheses of the literature on definitions, theoretical underpinnings, operationalizations, and response shift methods. They outlined areas in need of further explication and refinement, and delineated additional implications for future research. RESULTS: First, the proposed response shift definition was further specified and its implications for the interpretation of results explicated in relation to former, published definitions. Second, the proposed theoretical model was further explained in relation to previous theoretical models and its implications for formulating research objectives highlighted. Third, ways to explore alternative explanations per response shift method and their implications for response shift detection and explanation were delineated. The implications of the diversity of the response shift methods for response shift research were presented. Fourth, the implications of the need to enhance the quality and reporting of the response shift studies for future research were sketched. CONCLUSION: With our work, we intend to contribute to a common language regarding response shift definitions, theory, and methods. By elucidating some of the major implications of earlier work, we hope to advance response shift research.

Is history of abuse predictive of eating disorders with binge-eating episodes through an effect mediated by impulsivity? A French longitudinal study.

BACKGROUND: In recent years, many studies have explored the associations among impulsivity, history of abuse, the emergence of eating disorders with episodes of binge eating (EDBE) and their severity. Nevertheless, factors associated with successful clinical outcomes of EDBE are still unknown. Our study aimed to test the hypothesis that a history of abuse is associated with unsuccessful clinical outcomes of EDBE through an effect mediated by impulsivity. METHODS: We assessed patients older than 15 years, 3 months with EDBE at inclusion and at 1 year. Recovery was defined as the absence of eating disorders at 1 year. A mediation analysis was performed by means of structural equation modelling. RESULTS: We included 186 patients in our analyses (54% bulimia nervosa, 29% anorexia nervosa binge eating/purging type and 17% binge-eating disorder); 179 (96%) were female. One-third (n = 63) of patients reported a history of abuse, and recovery was observed for 20% of the sample (n = 38). Contrary to our assumption, a history of abuse was not associated with the absence of recovery of EDBE at 1 year. Factors unfavourable for achieving recovery were anxiety disorders (odds ratio [OR] 0.41), vomiting (OR 0.39), physical hyperactivity (OR 0.29), negative urgency and a lack of perseverance (OR 0.85 for both). Only positive urgency was positively associated with recovery (OR 1.25). LIMITATIONS: We excluded 219 patients lost to the 1-year follow-up. CONCLUSION: Our findings may help to deconstruct the empirical belief that traumatic events may interfere with the successful course of treatment for eating disorders. A high level of positive urgency may be associated with more receptivity to care.

Toward a rigorous assessment of the statistical performances of methods to estimate the Minimal Important Difference of Patient-Reported Outcomes: A protocol for a large-scale simulation study.

Interpreting observed changes over time in Patient-Reported Outcomes (PRO) measures is still considered a challenge. Indeed, concluding an observed change at group level is statistically significant does not necessarily equate this change is meaningful from the perspective of the patient. To help interpret within and/or between group changes in the measure over time, the estimation of the Minimal Important Difference (MID) of the instrument - the smallest value that patients consider as a perceived change - is useful. In the last 30 years, a plethora of methods and estimators have been proposed to derive this MID value using clinical data from sample of patients. MIDs for hundreds of PROs have been estimated, with frequently a substantial variability in the results depending on the method used. Nonetheless, a rigorous assessment of the statistical performances of numerous proposed methods for estimating MIDs by experimental design such as Monte-Carlo study has never been performed. The purpose of this paper is to thoroughly depict a protocol for a large-scale simulation study designed to investigate the statistical performances, especially bias against a true populational value, of the common proposed estimators for MID. This paper depicts how investigated methods and estimators were retained after the conduct of a systematic review, the design of a conceptual model that formally defines what is the true populational MID value and the translation of the conceptual model into a model allowing the simulation of responses of items to a hypothetical PRO at two times of measurement along with the response to a Patient Global Rating of Change at the second time under the constraint of a known true MID value. A statistical analysis plan is depicted in order to conclude if working hypotheses on what could be appropriate MID estimators will be verified. Strengths, assumptions, and limits of the simulation model are exposed. Finally, we show how this protocol could be the basis for fostering future methodological research on the issue of interpreting changes in PRO measures.

Basket clinical trial design for targeted therapies for cancer: a French National Authority for Health statement for health technology assessment.

During the past decade, health technology assessment bodies have faced new challenges in establishing the benefits of new drugs for individuals and health-care systems. A topic of increasing importance to the field of oncology is the so-called agnostic regulatory approval of targeted therapies for cancer (independent of tumour location and histology) granted on the basis of basket trials. Basket trials in oncology offer the advantage of simultaneously evaluating treatments for multiple tumours, even rare cancers, in a single clinical trial. To address the novel challenges introduced by these trials, an interdisciplinary panel was convened on behalf of the Transparency Committee of the French National Authority for Health to clarify an approach designed to guarantee a transparent, reproducible, and fair assessment of histology-agnostic treatments for reimbursement by the French National Health Insurance Fund. The requirements of this approach include the need for randomisation, clinically relevant endpoints, appropriate correction for multiple significance testing, characterisation of subgroup heterogeneity, and validation of underlying biomarker assays. A prospectively designated external control is encouraged when the implementation of a direct comparison is deemed infeasible. We also underline the importance of recording outcomes from basket trials in a registry for use as future external controls.

The minimal perceived change: a formal model of the responder definition according to the patient's meaning of change for patient-reported outcome data analysis and interpretation.

BACKGROUND: Patient-Reported Outcomes (PROs) are standardized questionnaires used to measure subjective outcomes such as quality of life in healthcare. They are considered paramount to assess the results of therapeutic interventions. However, because their calibration is relative to internal standards in people's mind, changes in PRO scores are difficult to interpret. Knowing the smallest value in the score that the patient perceives as change can help. An estimator linking the answers to a Patient Global Rating of Change (PGRC: a question measuring the overall feeling of change) with change in PRO scores is frequently used to obtain this value. In the last 30 years, a plethora of methods have been used to obtain these estimates, but there is no consensus on the appropriate method and no formal definition of this value. METHODS: We propose a model to explain changes in PRO scores and PGRC answers. RESULTS: A PGRC measures a construct called the Perceived Change (PC), whose determinants are elicited. Answering a PGRC requires discretizing a continuous PC into a category using threshold values that are random variables. Therefore, the populational value of the Minimal Perceived Change (MPC) is the location parameter value of the threshold on the PC continuum defining the switch from the absence of change to change. CONCLUSIONS: We show how this model can help to hypothesize what are the appropriate methods to estimate the MPC and its potential to be a rigorous theoretical basis for future work on the interpretation of change in PRO scores.

Response shift in patient-reported outcomes: definition, theory, and a revised model.

PURPOSE: The extant response shift definitions and theoretical response shift models, while helpful, also introduce predicaments and theoretical debates continue. To address these predicaments and stimulate empirical research, we propose a more specific formal definition of response shift and a revised theoretical model. METHODS: This work is an international collaborative effort and involved a critical assessment of the literature. RESULTS: Three main predicaments were identified. First, the formal definitions of response shift need further specification and clarification. Second, previous models were focused on explaining change in the construct intended to be measured rather than explaining the construct at multiple time points and neglected the importance of using at least two time points to investigate response shift. Third, extant models do not explicitly distinguish the measure from the construct. Here we define response shift as an effect occurring whenever observed change (e.g., change in patient-reported outcome measures (PROM) scores) is not fully explained by target change (i.e., change in the construct intended to be measured). The revised model distinguishes the measure (e.g., PROM) from the underlying target construct (e.g., quality of life) at two time points. The major plausible paths are delineated, and the underlying assumptions of this model are explicated. CONCLUSION: It is our hope that this refined definition and model are useful in the further development of response shift theory. The model with its explicit list of assumptions and hypothesized relationships lends itself for critical, empirical examination. Future studies are needed to empirically test the assumptions and hypothesized relationships.

Response shift in results of patient-reported outcome measures: a commentary to The Response Shift-in Sync Working Group initiative.

PURPOSE: The Working Group undertook a critical, comprehensive synthesis of the response shift work to date. We aimed to (1) describe the rationale for this initiative; (2) outline how the Working Group operated; (3) summarize the papers that comprise this initiative; and (4) discuss the way forward. METHODS: Four interdisciplinary teams, consisting of response shift experts, external experts, and new investigators, prepared papers on (1) definitions and theoretical underpinnings, (2) operationalizations and response shift methods, (3) implications for healthcare decision-making, and (4) on the published magnitudes of response shift effects. Draft documents were discussed during a two-day meeting. Papers were reviewed by all members. RESULTS: Vanier and colleagues revised the formal definition and theory of response shift, and applied these in an amended, explanatory model of response shift. Sébille and colleagues conducted a critical examination of eleven response shift methods and concluded that for each method extra steps are required to make the response shift interpretation plausible. Sawatzky and colleagues created a framework for considering the impact of response shift on healthcare decision-making at the level of the individual patient (micro), the organization (meso), and policy (macro). Sajobi and colleagues are conducting a meta-analysis of published response shift effects. Preliminary findings indicate that the mean effect sizes are often small and variable across studies that measure different outcomes and use different methods. CONCLUSION: Future response shift research will benefit from collaboration among diverse people, formulating alternative hypotheses of response shift, and conducting the most conclusive studies aimed at testing these (falsification).

Practical issues encountered while determining Minimal Clinically Important Difference in Patient-Reported Outcomes.

BACKGROUND: Using a real dataset, we highlighted several major methodological issues raised by the estimation of the Minimal Clinically Important Difference (MCID) of a Patient-Reported Outcomes instrument. We especially considered the management of missing data and the use of more than two times of measurement. While inappropriate missing data management and inappropriate use of multiple time points can lead to loss of precision and/or bias in MCID estimation, these issues are almost never dealt with and require cautious considerations in the context of MCID estimation. METHODS: We used the LIGALONGO study (French Randomized Controlled Trial). We estimated MCID on the SF-36 General Health score by comparing many methods (distribution or anchor-based). Different techniques for imputation of missing data were performed (simple and multiple imputations). We also consider all measurement occasions by longitudinal modeling, and the dependence of the score difference on baseline. RESULTS: Three hundred ninety-three patients were studied. With distribution-based methods, a great variability in MCID was observed (from 3 to 26 points for improvement). Only 0.2 SD and 1/3 SD distribution methods gave MCID values consistent with anchor-based methods (from 4 to 7 points for improvement). The choice of missing data imputation technique clearly had an impact on MCID estimates. Simple imputation by mean score seemed to lead to out-of-range estimate, but as missing not at random mechanism can be hypothesized, even multiple imputations techniques can have led to an slight underestimation of MCID. Using 3 measurement occasions for improvement led to an increase in precision but lowered estimates. CONCLUSION: This practical example illustrates the substantial impact of some methodological issues that are usually never dealt with for MCID estimation. Simulation studies are needed to investigate those issues. TRIAL REGISTRATION: NCT01240772 (ClinicalTrials.gov) registered on November 15, 2010.

An updated matrix to predict rapid radiographic progression of early rheumatoid arthritis patients: pooled analyses from several databases.

OBJECTIVE: In early RA, some patients exhibit rapid radiographic progression (RRP) after one year, associated with poor functional prognosis. Matrices predicting this risk have been proposed, lacking precision or inadequately calibrated. We developed a matrix to predict RRP with high precision and adequate calibration. METHODS: Post-hoc analysis by pooling individual data from cohorts (ESPOIR and Leuven cohorts) and clinical trials (ASPIRE, BeSt and SWEFOT trials). Adult DMARD-naïve patients with active early RA for which the first therapeutic strategy after inclusion was to prescribe methotrexate or leflunomide were included. A logistic regression model to predict RRP was built. The best model was selected by 10-fold stratified cross-validation by maximizing the Area Under the Curve. Calibration and discriminatory power of the model were checked. The probabilities of RRP for each combination of levels of baseline characteristics were estimated. RESULTS: 1306 patients were pooled. 20.6% exhibited RRP. Four predictors were retained: rheumatoid factor positivity, presence of at least one RA erosion on X-rays, CRP > 30mg/l, number of swollen joints. The matrix estimates RRP probability for 36 combinations of level of baseline characteristics with a greatly enhanced precision compared with previously published matrices (95% CI: from ± 0.02 minimum to ± 0.08 maximum) and model calibration is excellent (P = 0.79). CONCLUSION: A matrix proposing RRP probability with high precision and excellent calibration in early RA was built. Although the matrix has moderate sensitivity and specificity, it is easily usable and may help physicians and patients to make treatment decisions in daily clinical practice.

Predictive Factors of Intraocular Pressure Level Evolution Over Time and Glaucoma Severity in Fuchs' Heterochromic Iridocyclitis.

Purpose: To investigate the clinical and virologic-associated and predictive factors of intraocular pressure (IOP) evolution over time and its severity in Fuchs' heterochromic iridocyclitis (FHC). Methods: Consecutive patients with both clinical FHC and intraocular synthesis of rubella virus (RV)-specific antibodies were included in this study. Specific ocular production of RV antibodies was confirmed using the quotient of serum/aqueous humor ratio of RV IgGs (Crv) and control antiviral IgGs (Cctl), using quantitative serology methods. Epidemiologic, clinical, biological, and virologic data at referral were collected and correlated with IOP values over time, occurrence, and severity of glaucoma. Results: Sixty-eight eyes of 68 patients were included. Mean age at diagnosis was 40.7 ± 11.1 years. Mean follow-up was 4.3 ± 4.3 years. Mean baseline Crv and Cctl values were 12.34 ± 14.67 and 216.70 ± 98.4, respectively. Mean baseline IOP was 17.2 ± 7.2 mm Hg (range, 9-40) and 15.6 ± 5.6 (range, 3-30) 5 years after referral. The predictive factors for pejorative IOP evolution over time and glaucoma severity were male sex (P = 0.03) and decreased Crv (P = 0.04) and presence of iris nodules (P < 0.001) and decreased Cctl (P = 0.02), respectively. Diagnostic delay was associated with increased likelihood of undergoing glaucoma surgery (P = 0.02). Conclusions: Time to diagnosis, male sex, presence of iris nodules at baseline, and decreased Crv and Cctl ratios were associated with increased likelihood of pejorative IOP evolution over time. Given the aggressiveness of glaucoma in FHC, these results provide interesting insight into what category of patients should need the closest screening.

Long-Term Cognitive Prognosis of Profoundly Deaf Older Adults After Hearing Rehabilitation Using Cochlear Implants.

OBJECTIVES: To analyze long-term cognitive status and function after cochlear implantation in profoundly deaf individuals. DESIGN: Prospective observational longitudinal study. SETTING: Ten academic medical centers referent for cochlear implantation. PARTICIPANTS: Individuals aged 65 and older who qualified for cochlear implantation (N=70). MEASUREMENTS: Cognitive tests were administered before cochlear implantation and 1 and 5 or more years after cochlear implantation. Evaluation consisted of 6 tests assessing attention, memory, orientation, executive function, mental flexibility, and fluency. Cognitive status was determined as normal, mild cognitive impairment (MCI), or dementia. Speech perception in quiet and noisy conditions was assessed using disyllabic words, and quality of life was assessed using the Nijmegen Cochlear Implant Questionnaire. RESULTS: Mean follow-up was 6.8 years (range 5.5-8.5 years). Speech perception scores and quality of life remained stable from 1 to 7 years after cochlear implantation. Of 31 participants (45%) with MCI before cochlear implantation, 2 (6%) developed dementia during follow-up, 19 (61%) remained stable, and 10 (32%) returned to normal cognition. None of the 38 with normal cognition developed dementia during follow-up, although 12 (32%) developed MCI. CONCLUSION: MCI is highly prevalent in older adults with profound hearing loss. Nevertheless, we observed a low rate of progression to dementia, and cognitive function improved in some individuals with MCI at baseline. These results highlight that cochlear implantation should be strongly considered in profoundly deaf individuals, even those with MCI, who may have a specific subtype of MCI, with a possible positive effect of hearing rehabilitation on neurocognitive functioning.

Role of electrophysiology in guiding near-total resection for preservation of facial nerve function in the surgical treatment of large vestibular schwannomas.

OBJECTIVE In large vestibular schwannoma (VS) surgery, the facial nerve (FN) is at high risk of injury. Near-total resection has been advocated in the case of difficult facial nerve dissection, but the amount of residual tumor that should be left and when dissection should be stopped remain controversial factors. The objective of this study was to report FN outcome and radiological results in patients undergoing near-total VS resection guided by electromyographic supramaximal stimulation of the FN at the brainstem. METHODS This study was a retrospective analysis of a prospectively maintained database. Inclusion criteria were surgical treatment of a large VS during 2014, normal preoperative FN function, and an incomplete resection due to the strong adherence of the tumor to the FN and the loss of around 50% of the response of supramaximal stimulation of the proximal FN at 2 mA. Facial nerve function and the amount and evolution of the residual tumor were evaluated by clinical examination and by MRI at a mean of 5 days postoperatively and at 1 year postoperatively. RESULTS Twenty-five patients met the inclusion criteria and were included in the study. Good FN function (Grade I or II) was observed in 16 (64%) and 21 (84%) of the 25 patients at Day 8 and at 1 year postoperatively, respectively. At the 1-year follow-up evaluation (n = 23), 15 patients (65%) did not show growth of the residual tumor, 6 patients (26%) had regression of the residual tumor, and only 2 patients (9%) presented with tumor progression. CONCLUSIONS Near-total resection guided by electrophysiology represents a safe option in cases of difficult dissection of the facial nerve from the tumor. This seems to offer a good compromise between the goals of preserving facial nerve function and achieving maximum safe resection.

Risk factors for pulmonary complications after hepatic resection: role of intraoperative hemodynamic instability and hepatic ischemia.

BACKGROUND: Postoperative operative pulmonary complications (PPCs) after hepatic surgery are associated with increased length of hospital stays. Intraoperative blood transfusion, extensive resection and different comorbidities have been identified. Other parameters, like time of hepatic ischemia, have neither been clinically studied, though experimental studies show that hepatic ischemia can provide lung injury. The objective of this study was to determinate the risk factors of postoperative pulmonary complications (PPCs) after hepatic resection within 7 postoperative days. METHOD: Ninety-four patients consecutively who underwent elective hepatectomy between January and December 2013. Demographic data, pathological variables, and preoperative, intraoperative, and postoperative variables had been prospectively collected in a data base. The dependant variables studied were the occurrence of PPCs, defined before analysis of the data. RESULTS: PPCs occurred in 32 (34%) patients. A multivariate analysis allowed identifying the risk factors for PPCs. On multivariate analysis, preoperative gamma-glutamyltransferase (GGT) elevation OR =5,12 [1,85-15,69] p = 0,002, liver ischemia duration OR = 1,03 [1,01-1,06] p = 0,01 and the intraoperative use of vasopressor OR = 4,40 [1,58-13,36] p = 0,006 were independently associated with PPCs. For every 10 min added in ischemia duration, the OR of the risk of PPCs was estimated to be 1.37 (CI95% = [1.08-1.81], p = 0.01). CONCLUSION: Three risk factors for PPCs have been identified in a population undergoing liver resection: preoperative GGT elevation, ischemia duration and the intraoperative use of vasopressor. PPCs after liver surgery could be related to lung injury induced by liver ischemia reperfusion and not solely by direct infectious process. That could explain why factors influencing directly or indirectly liver ischemia were independently associated with PPCs.

Cost-Effectiveness of TNF-Blocker Injection Spacing for Patients with Established Rheumatoid Arthritis in Remission: An Economic Evaluation from the Spacing of TNF-Blocker Injections in Rheumatoid Arthritis Trial.

BACKGROUND: In patients with rheumatoid arthritis in remission, a disease activity-driven tapering of adalimumab or etanercept relying on progressive injection spacing has not been shown to be equivalent to a maintenance strategy at full dose in terms of disease activity in the Spacing of TNF-blocker injections in Rheumatoid ArthritiS Study (STRASS) trial. OBJECTIVES: To evaluate the cost-effectiveness of such a spacing strategy based on the data of the STRASS trial. METHODS: This is a cost-utility analysis of the STRASS trial, a French multicenter 18-month equivalence randomized open-label controlled trial that included patients at stable dose for at least 1 year, in remission for at least 6 months. Effectiveness was assessed in quality-adjusted life-years (QALYs). Costs involved in the study period were assessed from a payer perspective. The decremental cost-effectiveness ratio (DCER) was calculated in the complete cases sample (n = 98). Several sensitivity analyses were conducted and the impact of missing data on DCER estimate was investigated. An acceptability analysis was performed. RESULTS: In the spacing arm, TNF-blockers were stopped for 34.1% of the patients, tapered for 43.2%, and maintained at full dose for 18.2%. The spacing strategy was associated with less QALYs gain (mean difference of -0.158; 95% confidence interval [CI] -0.085 to -0.232) and reduced costs (mean difference of -€8,440; 95% CI -6,507 to -10,212). The estimated DCER of the spacing strategy over the maintenance at full dose was €53,417 saved per QALY lost (95% CI 32,230 to 104,700). CONCLUSIONS: The spacing strategy appears cost-effective, but the acceptability of such a QALY loss reported to the cost avoided remains to be evaluated, because no consensual threshold has been determined for willingness to accept as compared with willingness to pay.

Multivariate Analysis of Factors Influencing Facial Nerve Outcome following Microsurgical Resection of Vestibular Schwannoma.

Objective To assess through multivariate analysis the clinical pre- and intraoperative factors of facial nerve outcomes at day 8 and 1-year recovery of facial palsy, as compared with day 8 status among patients who underwent total resection of unilateral vestibular schwannoma. Study Design Case series with chart review. Setting Tertiary referral center. Subjects and Methods This study included 229 patients with preoperative normal facial function and anatomic preservation of the facial nerve. Clinical, radiologic, and intraoperative factors were assessed according to facial nerve function at day 8 and 1 year. Results We observed that 74% and 84% of patients had good facial function (House-Brackmann [HB] I-II) at day 8 and 1 year, respectively. Of 60 patients, 26 (43%) who had impaired facial function (HB III-VI) at day 8 recovered good facial function (HB I-II) 1 year after surgery. A structured equation model showed that advanced tumor stage and strong facial nerve adhesion were independently associated with facial nerve conduction block at day 8. No predictive factor of impaired facial function recovery was seen at 1 year. In terms of the extracanalicular diameter of the tumor, the cutoff point to minimize the risk of impaired facial function was 16 mm. Conclusion At day 8 after vestibular schwannoma resection, facial function was impaired in the case of large tumors or strong facial nerve adhesion to the tumor. After 1 year, less than half of the patients recovered good facial function, and no predictive factor was found to be associated with this possible recovery.