Category: Statistics

Trials. 2023 Sep 5;24(1):572. doi: 10.1186/s13063-023-07601-9.

ABSTRACT

BACKGROUND: International guidelines of groin hernia treatment strongly recommend to fixate the mesh in large M3 medial defects during TAPP/TEP procedures. The main purpose of fixation is to decrease the recurrence rate which is alarmingly high in case of those defects. In 2022, a team consisting of hernia surgeons and scientists from universities of technology conducted an experimental study with the use of 3D groin model to verify the hypothesis that fixation is not necessary in above cases. Experiment showed that rigid and anatomically shaped meshes are able to maintain its position in the groin without fixation. Similar conclusions were recently published in Swedish database registry analysis. To confirm above results, we decided to conduct a multicenter randomized controlled trial.

METHODS: Main objective of MEFI Trial is to verify the hypothesis that non-fixation of spatial, standard polypropylene meshes is non-inferior to fixation of flat, polypropylene lightweight meshes in M3 hernias by laparoendoscopic approach. Eleven large surgery centers in Poland having proficiency in laparoendoscopic groin hernia repairs were recruited for this study. Recurrence in 12-month follow-up was set as a primary endpoint. Pain sensation (Visual Analog Scale) and incidence of other complications (hematoma, seroma, SSI) were also noted. Based on the statistical analysis, minimal sample size in both arms was established at 83-102. The first arm (control) consists of patients undergoing a repair with the use of a flat, macroporous mesh with fixation using histoacryl glue. In the second arm, patients will be operated with the use of anatomically shaped, standard-weight mesh without fixation. Study will be double-blinded (patient/surgeon). After the dissection of preperitoneal space, surgeon will open a sealed envelope and find out which technique he will have to perform. Follow-up will be performed by Study Secretary (also blinded to the method used) via phone call 3 and 12 months after surgery.

DISCUSSION: Based on experimental study and recent registry analysis, we believe that the recurrence rate in both groups would be on the same level, giving hernia societies a strong argument for amending the guidelines.

TRIAL REGISTRATION: ClinicalTrials.gov NCT05678465. Registered on 10 January 2023.

PMID:37670376 | DOI:10.1186/s13063-023-07601-9

Reprod Biol Endocrinol. 2023 Sep 5;21(1):83. doi: 10.1186/s12958-023-01132-3.

ABSTRACT

BACKGROUND: There was inconsistency in optimal endometrial preparation protocol for frozen-thawed embryo transfer (FET) in patients with endometriosis. We conducted this study to investigate the effect of different endometrial preparation protocols on the pregnancy outcomes in patients with endometriosis undergoing FET cycles, and determine the optimal number of GnRHa injections in GnRHa-HRT protocols.

METHOD(S): This was a retrospective cohort analysis of women with endometriosis who underwent FET cycles at a single university-based center. This study retrospectively analyzed 2048 FET cycles in our center from 2011 to 2020. According to the endometrial preparation protocols, patients were divided into 4 groups: gonadotropin releasing hormone agonist-hormone replacement therapy(GnRHa-HRT), hormone replacement therapy(HRT), ovulation induction(OI), and natural cycle(NC). In the GnRHa-HRT group, patients were further divided into 3 groups: one injection of GnRHa, two injections of GnRHa, and three or more injections of GnRHa. The primary outcome was the clinical pregnancy rate. Propensity score matching was used to adjust for potential non-similarities among the groups. Multivariate logistic regression analysis was performed to figure out the risk factors for pregnancy outcomes.

RESULT(S): There were no statistical differences in pregnancy outcomes among the four endometrial preparation protocols in FET cycles with endometriosis patients, the results retained after propensity score matching(PSM). And in endometriosis patients complicated with adenomyosis, the results remained similar. In patients with GnRHa-HRT protocol, there were no differences in clinical pregnancy rate and live birth rate with different numbers of GnRHa injections, the early miscarriage rate were 18% in the two injections of GnRHa group and 6.5% in the one injection of GnRHa group(P = 0.017). Multifactorial logistic regression analysis showed that two injections of GnRHa before FET was associated with increased early miscarriage rate compared with one injection of GnRHa[adjusted OR (95% CI): 3.116(1.079-8.998),p = 0.036].

CONCLUSION(S): The four kinds of endometrial preparation protocols for FET, GnRHa-HRT, HRT, OI and NC had similar pregnancy outcomes in patients with endometriosis. In endometriosis patients complicated with adenomyosis, the results remained similar. In patients with endometriosis undergoing GnRHa-HRT protocol for FET, more injections of GnRHa had no more advantages in pregnancy outcomes, on the contrary, it might increase the early miscarriage rate.

PMID:37670354 | DOI:10.1186/s12958-023-01132-3

BMC Palliat Care. 2023 Sep 6;22(1):129. doi: 10.1186/s12904-023-01248-8.

ABSTRACT

BACKGROUND: The Emergency Department (ED) is not always the optimal place for people with palliative care needs but is the most common route for treatment when urgent care is sought. The aim of this study,”REasons for PalLIative Care Admissions (REPLICA)’ was to explore the perspectives of ED healthcare professionals of hospital admission or discharge via ED for palliative care patients.

METHODS: This is a sequential mixed methods study comprising (i) quantitative descriptive analysis of Hospital Episode Statistics (HES) of palliative care patients (code Z51.5) who were admitted through ED in a West Midlands Hospital and for the rest of England; (ii) in-depth semi-structured interviews with 17 ED staff which were analysed using thematic content analysis.

RESULTS: Over the four years (2013-2017), 430,116 people admitted through ED were identified with a Z51.5 diagnosis code, 0.6% (n = 2736) of whom were from the West Midlands Hospital. The most common reasons for palliative care patients’ admission to hospitals across England were for care of chronic kidney disease, cancers and urinary tract infections. Five themes were elicited from the qualitative analysis: (1) Providing palliative care in ED is challenging, due to factors including lack of training in palliative care and the unsuitable environment. (2) Patients go to ED due to challenges in community management such as inappropriate referrals and no care plan in place. (3) Health system influences admission and discharge decisions, including bed availability and being unable to set up community services out-of-hours. (4) Discussion with patient about treatment and end of life care needs to be outside of ED whilst the patient is still well enough to express their wishes. (5) Improving services for patients with palliative care needs. Recommendations include short training sessions for ED staff and accessing palliative care professionals 24/7.

CONCLUSIONS: A large number of palliative care patients visit ED and are admitted to hospital for care; there is an urgent need to prevent patients attending the hospital through the establishment of a coordinated and dedicated service to support palliative care patients in the community.

PMID:37670312 | DOI:10.1186/s12904-023-01248-8

Arch Cardiol Mex. 2023 Sep 5. doi: 10.24875/ACM.22000095. Online ahead of print.

ABSTRACT

INTRODUCTION: The COVID-19 pandemic brought with it a large number of adverse consequences for public health with serious socioeconomic repercussions. In this study we characterize the social, demographic, morbidity and mortality conditions of individuals treated for COVID-19 in one of the SARS-CoV-2 reference hospitals in Mexico City.

METHOD: A descriptive cross-sectional study was carried out in 259 patients discharged from the Instituto Nacional de Cardiología Ignacio Chávez, between April 11, 2020 and March 14, 2021. A multivariate logistic regression model was used to identify the association between sociodemographic and clinical variables. An optimization was performed using maximum likelihood calculations to choose the best model compatible with the data. The maximum likelihood model was evaluated using ROC curves, goodnessof-fit estimators, and multicollinearity analysis. Statistically significant patterns of comorbidities were inferred by evaluating a hypergeometric test over the frequencies of co-occurrence of pairs of conditions. A network analysis was implemented to determine connectivity patterns based on degree centrality, between comorbidities and outcome variables.

RESULTS: The main social disadvantages of the studied population are related to the lack of social security (96.5%) and the lag in housing conditions (81%). Variables associated with the probability of survival were being younger (p < 0.0001), having more durable material goods (p = 0.0034) and avoiding: pneumonia (p = 0.0072), septic shock (p < 0.0001) and acute respiratory failure (p < 0.0001); (AUROC: 91.5%). The comorbidity network for survival cases has a high degree of connectivity between conditions such as cardiac arrhythmias and essential arterial hypertension (Degree Centrality = 90 and 78, respectively).

CONCLUSIONS: Given that among the factors associated with survival to COVID-19 there are clinical, sociodemographic and social determinants of health variables, in addition to age; It is imperative to consider the various factors that may affect or modify the health status of a population, especially when addressing emerging epidemic phenomena such as the current COVID-19 pandemic.

PMID:37669561 | DOI:10.24875/ACM.22000095

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):697-708. doi: 10.11607/jomi.10055.

ABSTRACT

Purpose: To evaluate the survival rate and marginal bone level (MBL) of calcium phosphate-blasted acid-etched titanium implants placed in a cohort of patients with different ridges after a follow-up period of at least 10 years. Materials and Methods: A total of 61 patients with a minimum implant follow-up of 10 years were selected for this historical prospective, best clinical practice cohort study. Between 2009 and 2012, 121 titanium implants were placed using a flap, flapless, or postextractive technique. The implant placement timing was performed according to pre-extractive diagnosis and divided into immediate (immediately after tooth extraction with an absence of infection), early (within 2 to 3 months with an acute periapical lesion), delayed (6 to 12 months from extraction with a large periapical infection), or late (> 12 months from extraction with healed edentulous ridges). All implants were loaded after 3 months with provisional and definitive cemented restorations. Periapical radiographs were taken before implant insertion and at 3, 6, 12, 24, 36, 48, 96, and 120 months (T3, T6, T12, T24, T36, T48, T96, and T120, respectively). The MBL was calculated in single blind by an additional examiner. Linear logistic regression was performed to analyze statistically significant differences in relation to different operative variables at all evaluation times. Multilevel mixed logistic regression was made to evaluate the factors associated to MBL at 10 years (T120). Results: After 10 years, 47 patients and 92 implant restorations were analyzed, showing that 88 implants (95.6%) survived and 4 implants (4.4%) failed. The cumulative drop-out rate was 22.1%. Loosening and/or mobility was observed in a total of 9 abutments (9.7%) during the observational time. No other complications were reported. Implants placed with a flapless technique revealed a similar MBL to those placed with a flap technique. No significant differences were observed between the surgical techniques at T96 and T120. Immediate and early implants revealed a more stable MBL than both delayed and late implants up to T48. At longer evaluation times (T96 and T120), the MBL values were not statistically significant (P > .05). Narrower diameter implants (3.5 mm) revealed a higher bone loss when compared to the 4.1-mm- and 5.0-mm-diameters, especially in the first year from implant insertion (from T3 to T12) and at longer follow-up (T36 and T48). After that, the difference was reduced. Multilevel analysis showed that none of these variables appear to significantly influence MBL at 120 months. Conclusions: MBL was not influenced by surgical technique or implant placement timing after 10 years. Maintaining a strict occlusal and hygiene control created the conditions to preserve bone integrity and achieve a high implant survival rate.

PMID:37669529 | DOI:10.11607/jomi.10055

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):643-650. doi: 10.11607/jomi.10478.

ABSTRACT

One of the most important parts of any research project is the statistical analysis through which results are described and deemed significant or otherwise. Given this role of statistical analyses, it is imperative to understand what statistical tests are available and, most importantly, when they are appropriate. This is because choosing an improper statistical test can lead to inaccurate results and meaningless conclusions. We have written this data analysis guide to assist dental researchers with carrying out a proper analysis plan in consultation with a statistician. In this first part, we detail common types of outcome and predictor variables and include some common tests that can be used for each scenario. Using different simulated datasets, we also provide examples of common data visualization techniques and how a proper statistical test can be applied. We hope this guide provides some general background knowledge on common statistical techniques and allows for easier and more effective conversations with your statistician.

PMID:37669527 | DOI:10.11607/jomi.10478

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):784-788. doi: 10.11607/jomi.10119.

ABSTRACT

Purpose: To evaluate differences in the temperature rise at the cervical area of one-piece vs two-piece implants during the setting of relined provisional crowns. Materials and Methods: A K-type thermocouple was fixed to the coronal thread of 15 one-piece implants and 15 two-piece implants that were mounted on a plexiglass apparatus. Baseline temperature (Bl Temp) was recorded before starting the curing process. The maximum temperature (Max Temp) reached during the process in both implant groups was also recorded. Total heat flux (THF) was calculated as well as the thermal amplitude (Temp-Amp) at the implant surface. Finally, the differences between the implant types were compared using unpaired t test. Results: The increase in temperature from baseline was statistically significantly greater in the one-piece implants than in the two-piece implants (P < .01). Similarly, the THF and Temp-Amp were significantly greater in the one-piece implants compared to two-piece implants (P < .01). Conclusions: The polymerization of PMMA-based resin temporary crowns produces a significant temperature rise in both one-piece and two-piece implants. It is advisable to use two-piece implants to restore immediately loaded implants to reduce the risk to implant surroundings that may occur due to the temperature rise at the implant neck.

PMID:37669526 | DOI:10.11607/jomi.10119

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):727-732. doi: 10.11607/jomi.10134.

ABSTRACT

Objective: To verify the effect of fiducial marker number and configuration on target registration error (TRE) for dynamic computer-aided zygomatic implant surgery. Material and Methods: All patients who underwent zygomatic implant surgery with navigation from January 2018 to December 2021 were enrolled. For each patient, 6 to 8 miniscrews were placed intraorally as fiducial markers before the surgery. After the registration procedure, the TRE, which represents the distance between the target of the image space and the real position of the fiducial markers, was calculated. SPSS (22.0) was used for statistical analysis. Results: A total of 325 titanium miniscrews were placed in 47 patients who underwent zygomatic implant placement by navigation. The lowest TRE was 0.2 mm, compared to the highest TRE of 1.9 mm. There was no significant difference in the mean TRE value among the different titanium miniscrew groups (P = .07). A total of 8 miniscrews in 7 patients were lost in the maxillary tuberosity area prior to and during navigation surgery, which resulted in an irregular polygonal distribution of fiducial markers. However, there was no statistically significant difference in TRE between a polygonal distribution (0.62 ± 0.35 mm) and an irregular polygonal distribution (0.68 ± 0.33 mm) (P = .35). Conclusion: A scattered, polygonal distribution with of a minimum of five fiducial markers in an edentulous maxilla could achieve acceptable TRE values in registration. It seems that the registration error was not influenced by the absence of one corner in a polygon distribution.

PMID:37669525 | DOI:10.11607/jomi.10134

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):667-680. doi: 10.11607/jomi.10142.

ABSTRACT

Purpose: To assess the literature comparing histologic levels of osseointegration for titanium vs zirconia dental implants. Materials and Methods: This systematic review was conducted following the PRISMA guidelines and was registered in PROSPERO (CRD42021236781). Electronic and manual searches were carried out through the PubMed/MEDLINE, PubMed Central, and Embase databases with a platform-specific search strategy combining controlled terms (MeSH and Emtree) and text words. The articles were selected by two independent investigators who evaluated the articles based on the criteria for eligibility. Results: A total of 17 articles were included. All were preclinical studies. The populations included dogs (27.55%), minipigs (14.28%), rats (14.28%), and rabbits (43.89%); and the implantation site varied among the mandible (36.82%), maxilla (9.04%), tibia (17.64%), skull (10.70%), and femur (25.80%). A total of 370 titanium (Ti) implants and 537 zirconia (Zr) implants were evaluated. The average osseointegration (% bone-to-implant contact) for Zr was 55.51% (17.6% to 89.09%), and for Ti was 58.50% (23.2% to 87.85%). There was no statistical difference between studies at the 2-month follow-up (P = .672), but this difference was significant at 1 and 3 months (P < .001). Conclusions: Within the limitations of this review, Zr implants had a similar level of osseointegration compared to Ti implants. Nonetheless, because these findings are based on preclinical research, all data must be carefully examined.

PMID:37669522 | DOI:10.11607/jomi.10142

Int J Oral Maxillofac Implants. 2023 Jul-Aug;38(4):733-738. doi: 10.11607/jomi.10096.

ABSTRACT

Purpose: To compare the stability of short vs standard (ie, regular-length) implants in the edentulous mandible. Materials and Methods: In this prospective clinical study, 20 patients with edentulous mandibles received four implants each-two short implants (4 mm) in the region of the first molar and two standard implants (≥ 10 mm) in the interforaminal region. Implant stability was assessed using resonance frequency analysis immediately after implant placement and at the day of the abutment connection after 3 months of healing in order to provide an implant stability quotient (ISQ). Results: Implant stability in the two implant groups at placement (ISQ: short 66.2; standard 68.2) and at abutment connection (ISQ: short 74.9; standard 75.7) did not differ substantially or statistically significantly (both P > .05). Findings did not change after statistically controlling for potential confounders such as bone quality and bone crest width. At abutment connection, 95% of the short and 97.5% of the standard implants demonstrated sufficient stability for conventional loading (P > .05). Conclusions: Short dental implants demonstrate similar primary and secondary stability compared to standard implants and seem to be a promising treatment option for rehabilitation of patients with edentulous mandibles.

PMID:37669521 | DOI:10.11607/jomi.10096