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1.
BMC Health Serv Res ; 23(1): 1051, 2023 Oct 02.
Article in English | MEDLINE | ID: mdl-37784095

ABSTRACT

INTRODUCTION: Vaccine hesitancy is recognized as a significant public health threats, characterized by delays, refusals, or reluctance to accept vaccinations despite their availability. This study, aimed to investigate the willingness of Iranians to receive booster shots, refusal rate, and their preferred type of COVID-19 vaccine. MATERIALS AND METHODS: This cross-sectional study was conducted over a month from August 23 to September 22, 2022 using an online questionnaire distributed through WhatsApp and Telegram online communities. The questionnaire assessed participants' intent to accept COVID-19 booster vaccination and had no exclusion criteria. Data analysis involved using SPSS version 16.0, with t-tests and chi-square tests used to assess the bivariate association of continuous and categorical variables. A multivariate logistic regression model was built to examine the association between Health Belief Model (HBM) tenets and COVID-19 vaccination intent. The Hosmer Lemeshow Goodness of Fit statistic was used to assess the model's fit, with a p-value > 0.05 indicating a good fit. RESULTS: The survey was disseminated to 1041 adults and the findings revealed that 82.5% of participants expressed a desire to receive the booster dose. Participants who intended to be vaccinated were generally older (46.4 ± 10.9), mostly female (53.3%), single (78.9%), had received a flu vaccine (45.8%). The findings indicated that the HBM items, including perception of COVID-19 disease, perceived benefits of COVID-19 vaccines, COVID-19 safety/cost concerns, preference of COVID-19 vaccine alternatives, and prosocial norms for COVID-19 vaccination, received higher scores among individuals intending to be vaccinated compared to vaccine-hesitant individuals, with statistical significance (p < 0.05). However, the "COVID-19 risk-reduction habits" item had a higher score but did not reach statistical significance (p = 0.167). CONCLUSION: Factors such as lack of trust in the effectiveness of the vaccine, trust in specific vaccine manufacturers, and concerns about side effects of COVID-19 vaccine are among the most important factors. These findings have implications for national vaccination policies, emphasizing the need for policymakers in the health sector to address these factors as vital considerations to ensure the continuity of vaccination as one of the most important strategies for controlling the pandemic.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Humans , Female , Male , Iran/epidemiology , COVID-19/epidemiology , COVID-19/prevention & control , Cross-Sectional Studies , Vaccination
2.
Foot Ankle Int ; 44(9): 825-833, 2023 09.
Article in English | MEDLINE | ID: mdl-37658714

ABSTRACT

BACKGROUND: We aimed to find the prevalence of peroneal tendon instability (PTI) accompanying different types of calcaneal fractures and to determine predictors of PTI based on preoperative CT scanning. METHODS: In a retrospective cross-sectional study, preoperative CT scans of 400 consecutive calcaneal fractures undergoing surgery were reviewed for comminuted fragments in the lateral gutter of the ankle, fractures at the tip of the lateral malleolus, dislocated peroneal tendons, excessive displacement of the lateral calcaneal wall, calcaneal fracture-dislocation, superior peroneal retinaculum (SPR) avulsion fracture (fleck sign), and shape of the retromalleolar groove. The correlation of these variables with intraoperative SPR stress test, defined as the diagnostic criteria for PTI in calcaneal fractures, was evaluated. RESULTS: In total, 369 patients (mean age, 39 ± 13; range, 11-72 years), with 321 (87.0%) of them male, were included. Among all calcaneal fractures, 67 cases (16.7%) had associated PTI as confirmed intraoperatively by an SPR stress test. A statistically significant association was found between PTI in calcaneal fractures and comminuted fragments in the lateral gutter of the ankle (P = .03), dislocated peroneal tendons (P < .001), calcaneal fracture-dislocation (P < .001), SPR avulsion fracture (P < .001), and Sanders type IV of calcaneal fracture (P = .02). There was no statistically significant relationship between PTI and the mechanism of injury (P = .98), side of fracture (P = .30), uni- or bilateral calcaneal fractures (P = .27), a fracture at the tip of lateral malleolus (P = .69), shape of the retromalleolar groove (P = .78), or excessive displacement of the lateral calcaneal wall (P = .06). The most specific CT finding to predict PTI accompanying calcaneal fractures was calcaneal fracture-dislocation (99.1%). CONCLUSION: Following calcaneal fracture fixation, PTI was confirmed with intraoperative SPR stress test in one-sixth of cases. With the exception of calcaneal fracture-dislocation, preoperative findings on CT scanning and calcaneal fracture pathoanatomy are insufficient to diagnose PTI accompanying calcaneal fractures. LEVEL OF EVIDENCE: Level III, retrospective case control study.


Subject(s)
Ankle Injuries , Fracture Dislocation , Fractures, Avulsion , Fractures, Bone , Fractures, Comminuted , Joint Dislocations , Humans , Male , Adult , Middle Aged , Case-Control Studies , Cross-Sectional Studies , Prevalence , Retrospective Studies , Fractures, Bone/diagnostic imaging , Fractures, Bone/surgery , Ankle Injuries/diagnostic imaging , Ankle Injuries/epidemiology , Ankle Injuries/surgery , Fractures, Comminuted/diagnostic imaging , Fractures, Comminuted/surgery
3.
Int J Prev Med ; 13: 130, 2022.
Article in English | MEDLINE | ID: mdl-36452471

ABSTRACT

Background: In the name of extensive vaccine uptake, understanding the public's attitude, perception, and intent toward COVID-19 vaccination is a significant challenge for public health officials. Methods: A cross-sectional survey via an online questionnaire rooted in the Health Belief Model and Integrated Behavioral Model was conducted to evaluate COVID-19 vaccination intent and its associated factors. Factor analysis and multivariate logistic regression were operated to be satisfactory. Results: Among the 4,933 respondents, 24.7% were health care workers, and 64.2% intended to accept COVID-19 vaccination. The adjusted odds (aOR) of COVID-19 vaccination intent was higher for individuals with greater exposure to social norms supportive of COVID-19 vaccination (aOR = 3.07, 95% Confidence Interval (CI) = 2.71, 3.47) and higher perceived benefits of COVID-19 vaccination (aOR = 2.9, 95% CI = 2.49, 3.38). The adjusted odds of vaccination intent were lower for individuals with greater COVID-19 vaccine safety concerns (aOR = 0.28, 95%CI = 0.25, 0.31). Lower vaccination intent was also associated with increasing age ((aOR = 0.99, 95% CI = 0.98, 0.999), female sex (aOR = 0.76, 95% CI = 0.65, 0.88), and working in the health care field (aOR = 0.75, 95% CI = 0.63, 0.9). Conclusions: The odds of COVID-19 vaccination intent were higher three or more times among those with a greater belief in vaccine effectiveness, lower concerns about vaccine safety, and greater exposure to cues to vaccinate, including from doctors. This last finding is concerning as vaccine acceptance was surprisingly lower among health care workers compared to others. The remarkable results of factor analysis and reliability of the questionnaire may encourage local health authorities to apply it to their regional population.

4.
Foot Ankle Spec ; : 19386400221125373, 2022 Sep 30.
Article in English | MEDLINE | ID: mdl-36181273

ABSTRACT

BACKGROUND: The aim of the study was to evaluate the clinical and functional outcomes following suturing of sheath of peroneal tendons to the calcaneal plate as an innovative technique for reduction of peroneal tendon instability (PTI) accompanying calcaneal fracture surgically treated via extensile lateral approach (ELA). METHODS: In a retrospective comparative study, among 245 operatively treated calcaneal fractures through ELA, we had 33 cases with PTI who underwent relocation of the peroneal tendons with ethibond suture in a figure-of-8 shape, passed through 2 parts of sheath of peroneal tendons and stitched to the calcaneal plate. Of the 33 cases, 12 were evaluated in the experimental group. Twelve surgically treated calcaneal fractures without PTI were matched as the control group. The outcome of the patients was assessed by American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale, Foot Function Index (FFI) percentage, Visual Analog Scale (VAS) pain, changes in Tegner activity level, maximal peroneal muscles strength testing, modified Star Excursion Balance Test (mSEBT), and triple hop for distance (THD) test. For the last 3 tests, the difference between operated and normal feet was calculated for each patient and this difference was compared between the 2 groups. RESULTS: There was no statistically significant difference between the 2 groups for AOFAS Ankle-Hindfoot Scale (P = .09), FFI percentage (P = .12), VAS pain (P = .73), changes in Tegner activity level (P = .87), maximal peroneal muscles strength testing (P = .45), mSEBT (P > .05), and THD (P = .87) tests. We had a case with point tenderness on retromalleolar groove and 4 cases with paresthesia in the territory of the sural nerve in the experimental group in contrary to one case of sural nerve paresthesia in the control group (P = .31). CONCLUSIONS: Relocation of peroneal tendons in PTI accompanying calcaneal fractures by fixing sheath of peroneal tendons to the calcaneal plate could be an acceptable procedure with good outcomes but may have increased chance of sural nerve injury. LEVELS OF EVIDENCE: Therapeutic, Level III: Retrospective.

5.
BMC Urol ; 22(1): 133, 2022 Aug 29.
Article in English | MEDLINE | ID: mdl-36038861

ABSTRACT

BACKGROUND: The significance of total and specific subpopulations of tumor-infiltrating lymphocytes (TILs) in cancer is now well-documented. In the present study, we investigated the relevance of CD3+, CD8 +, CD45RO +, and FOXP3 + TILs to the prognosis and survival of patients with bladder cancer and the disease's clinical-pathological parameters. METHODS: Infiltration of each subset was immunohistochemically evaluated in both stromal and intratumoral regions of tumor tissues from 85 patients with urothelial cell carcinoma of the bladder, with known survival. RESULTS: Our results indicated that intratumoral CD45RO+ lymphocytes were significantly higher in high-grade tumors than in low-grade ones (P = 0.028). The frequencies of intratumoral CD3+ (P = 0.002), CD8 + (P = 0.008), intratumoral (P = 0.002), and stromal (P = 0.017) CD45RO+ lymphocytes were also higher in patients with muscular invasion than those without invasion. The frequencies of intratumoral CD3+ (P = 0.043), CD8+ (P = 0.003), CD45RO+ (P = 0.023), and total CD45RO+ (P = 0.015), showed variation in patients with different T-stage, as well; mostly increased in T2 versus Ta and T1. Comparing patients in different stages revealed an increase in the frequencies of total CD3+ (P = 0.011), intratumoral CD3+ (P = 0.006), total CD8+ (P = 0.012), intratumoral CD8+ (P = 0.009) and stromal CD8+ (P = 0.034), as well as total and stromal CD45RO+ lymphocytes (P = 0.01 and P = 0.034, respectively) in stage II comparing to stage I, while the frequencies of stromal CD3+ (P = 0.077) and CD8+ (P = 0.053) cells tended to be decreased in stage III compared to stage II. CONCLUSIONS: We collectively observed that the frequency of immune cells, especially CD45RO+, CD3+, and CD8+ lymphocytes, were significantly higher in early-progressed tumors. This observation could be explained by continuous and prolonged stimulation of immune cells with tumor antigens during tumor progression or an increase in the recruiting factors, especially in the early stages, to eliminate tumor cells. However, with tumor progression to the late stages, the inhibitory microenvironment provided by tumor cells suppresses or changes the functionality of the effector and memory immune cells to help tumor growth. However, more functional studies with larger sample sizes are needed to reveal the real status of the immune system in patients with bladder cancer.


Subject(s)
Carcinoma, Transitional Cell , Urinary Bladder Neoplasms , Biomarkers , CD8-Positive T-Lymphocytes/pathology , Carcinoma, Transitional Cell/pathology , Humans , Leukocyte Common Antigens , Lymphocytes, Tumor-Infiltrating/pathology , Prognosis , Tumor Microenvironment , Urinary Bladder Neoplasms/pathology
6.
EXCLI J ; 21: 93-103, 2022.
Article in English | MEDLINE | ID: mdl-35221837

ABSTRACT

The aim of this study was to investigate the COVID-19 vaccination acceptance rate and its determinants among healthcare workers in a multicenter study. This was a cross-sectional multi-center survey conducted from February 5 to April 29, 2021. The questionnaire consisted of 26 items in 6 subscales. The English version of the questionnaire was translated into seven languages and distributed through Google Forms using snowball sampling; a colleague in each country was responsible for the forward and backward translation, and also the distribution of the questionnaire. A forward stepwise logistic regression was utilized to explore the variables and questionnaire factors tied to the intention to COVID-19 vaccination. 4630 participants from 91 countries completed the questionnaire. According to the United Nations Development Program 2020, 43.6 % of participants were from low Human Development Index (HDI) regions, 48.3 % high and very high, and 8.1 % from medium. The overall vaccination hesitancy rate was 37 %. Three out of six factors of the questionnaire were significantly related to intention to the vaccination. While 'Perceived benefits of the COVID-19 vaccination' (OR: 3.82, p-value<0.001) and 'Prosocial norms' (OR: 5.18, p-value<0.001) were associated with vaccination acceptance, 'The vaccine safety/cost concerns' with OR: 3.52, p-value<0.001 was tied to vaccination hesitancy. Medical doctors and pharmacists were more willing to take the vaccine in comparison to others. Importantly, HDI with OR: 12.28, 95 % CI: 6.10-24.72 was a strong positive determinant of COVID-19 vaccination acceptance. This study highlighted the vaccination hesitancy rate of 37 % in our sample among HCWs. Increasing awareness regarding vaccination benefits, confronting the misinformation, and strengthening the prosocial norms would be the primary domains for maximizing the vaccination coverage. The study also showed that the HDI is strongly associated with the vaccination acceptance/hesitancy, in a way that those living in low HDI contexts are more hesitant to receive the vaccine.

7.
Chin J Traumatol ; 25(3): 170-176, 2022 May.
Article in English | MEDLINE | ID: mdl-35101294

ABSTRACT

PROPOSE: In this study, we re-assessed the criteria defined by the radiological society of North America (RSNA) to determine novel radiological findings helping the physicians differentiating COVID-19 from pulmonary contusion. METHODS: All trauma patients with blunt chest wall trauma and subsequent pulmonary contusion, COVID-19-related signs and symptoms before the trauma were enrolled in this retrospective study from February to May 2020. Included patients (Group P) were then classified into two groups based on polymerase chain reaction tests (Group Pa for positive patients and Pb for negative ones). Moreover, 44 patients from the pre-pandemic period (Group PP) were enrolled. They were matched to Group P regarding age, sex, and trauma-related scores. Two radiologists blindly reviewed the CT images of all enrolled patients according to criteria defined by the RSNA criteria. The radiological findings were compared between Group P and Group PP; statistically significant ones were re-evaluated between Group Pa and Group Pb thereafter. Finally, the sensitivity and specificity of each significant findings were calculated. The Chi-square test was used to compare the radiological findings between Group P and Group PP. RESULTS: In the Group PP, 73.7% of all ground-glass opacities (GGOs) and 80% of all multiple bilateral GGOs were detected (p < 0.001 and p = 0.25, respectively). Single bilateral GGOs were only seen among the Group PP. The Chi-square tests showed that the prevalence of diffused GGOs, multiple unilateral GGOs, multiple consolidations, and multiple bilateral consolidations were significantly higher in the Group P (p = 0.001, 0.01, 0.003, and 0.003, respectively). However, GGOs with irregular borders and single consolidations were more significant among the Group PP (p = 0.01 and 0.003, respectively). Of note, reticular distortions and subpleural spares were exclusively detected in the Group PP. CONCLUSION: We concluded that the criteria set by RSNA for the diagnosis of COVID-19 are not appropriate in trauma patients. The clinical signs and symptoms are not always useful either. The presence of multiple unilateral GGOs, diffused GGOs, and multiple bilateral consolidations favor COVID-19 with 88%, 97.62%, and 77.7% diagnostic accuracy.


Subject(s)
COVID-19 , Contusions , Lung Injury , Contusions/diagnostic imaging , Humans , Lead , Lung/diagnostic imaging , Lung Injury/diagnostic imaging , Lung Injury/etiology , Retrospective Studies , SARS-CoV-2 , Tomography, X-Ray Computed/methods
8.
Biomed Res Int ; 2021: 6854477, 2021.
Article in English | MEDLINE | ID: mdl-34957307

ABSTRACT

Assessing differential item functioning (DIF) using the ordinal logistic regression (OLR) model highly depends on the asymptotic sampling distribution of the maximum likelihood (ML) estimators. The ML estimation method, which is often used to estimate the parameters of the OLR model for DIF detection, may be substantially biased with small samples. This study is aimed at proposing a new application of the elastic net regularized OLR model, as a special type of machine learning method, for assessing DIF between two groups with small samples. Accordingly, a simulation study was conducted to compare the powers and type I error rates of the regularized and nonregularized OLR models in detecting DIF under various conditions including moderate and severe magnitudes of DIF (DIF = 0.4 and 0.8), sample size (N), sample size ratio (R), scale length (I), and weighting parameter (w). The simulation results revealed that for I = 5 and regardless of R, the elastic net regularized OLR model with w = 0.1, as compared with the nonregularized OLR model, increased the power of detecting moderate uniform DIF (DIF = 0.4) approximately 35% and 21% for N = 100 and 150, respectively. Moreover, for I = 10 and severe uniform DIF (DIF = 0.8), the average power of the elastic net regularized OLR model with 0.03 ≤ w ≤ 0.06, as compared with the nonregularized OLR model, increased approximately 29.3% and 11.2% for N = 100 and 150, respectively. In these cases, the type I error rates of the regularized and nonregularized OLR models were below or close to the nominal level of 0.05. In general, this simulation study showed that the elastic net regularized OLR model outperformed the nonregularized OLR model especially in extremely small sample size groups. Furthermore, the present research provided a guideline and some recommendations for researchers who conduct DIF studies with small sample sizes.


Subject(s)
Psychometrics/methods , Computer Simulation , Humans , Likelihood Functions , Logistic Models , Machine Learning , Models, Statistical , Sample Size , Surveys and Questionnaires
9.
Foot Ankle Spec ; : 19386400211055274, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34724836

ABSTRACT

BACKGROUND: The aim of this study was to determine morphological variations and normal parameters of the cross-sectional tibiofibular syndesmotic anatomy. METHODS: Configurations of syndesmosis, anterior syndesmotic width (ASW), posterior syndesmotic width (PSW), and overlap distance, defined as the overlap of medial fibula with a drawn line from tip of anterior tubercle of incisura fibularis to the posterior tip, were measured on normal computed tomography (CT) scans of 110 cases. Results: Seventy seven male (70%) and 33 female (30%) (left: 50 and right: 60) were assessed. Mean age of the cases was 33 ± 13 (range: 15-80) years. Three different syndesmotic configurations were crescent (55.5%), rectangular (39.1 %), and semicircle (5.4 %). Overall, mean ASW, PSW, and overlap distance were 2.72, 3.98, and 1.02 mm, respectively. Upper limit of normal ASW in crescent, rectangular, and semicircle was 4.80, 4.85, and 3.89 mm, respectively. The maximum of PSW in crescent, rectangular, and semicircle was 6.25, 6.50, and 4.97 mm, respectively. There was not significant difference between syndesmotic configurations based on age (P = .69) and sex (P = .16). CONCLUSIONS: During interpreting axial CT scan to diagnose syndesmotic injuries, the normal range of parameters according to the different configurations of the tibiofibular syndesmosis should be carefully considered. LEVEL OF EVIDENCE: Level 4.

10.
Trauma Surg Acute Care Open ; 6(1): e000726, 2021.
Article in English | MEDLINE | ID: mdl-34222675

ABSTRACT

OBJECTIVES: The triage of trauma patients with potential COVID-19 remains a major challenge given that a significant number of patients may be asymptomatic or pre-symptomatic. This study aimed to compare the specificity and sensitivity of available triage systems for COVID-19 among trauma patients. Furthermore, it aimed to develop a novel triage system for SARS-CoV-2 detection among trauma patients in centers with limited resources. METHODS: All patients referred to our center from February to May 2020 were enrolled in this prospective study. We evaluated the SARS-CoV-2 triage protocols from the WHO, the Iranian Ministry of Health and Medical Education (MOHME), and the European Centre for Disease Control and Prevention (ECDC) for their effectiveness in finding COVID-19 infected individuals among trauma patients. We then used these data to design a stepwise triage protocol to detect COVID-19 positive patients among trauma patients. RESULTS: According to our findings, the WHO protocol showed 100% specificity and 13.3% sensitivity. The MOHME protocol had 99% specificity and 23.3% sensitivity. While the ECDC protocol showed 93.3% sensitivity and 89.5% specificity, it did not prioritize patients based on traumatic injuries and unstable conditions. Our stepwise triage protocol, which prioritizes traumatic injuries, had 93.3% sensitivity and 90.3% specificity. CONCLUSION: Our study shows that the triage protocols from the WHO, MOHME and ECDC are not best equipped to diagnose SARS-CoV-2 infected individuals among trauma patients. In our proposed stepwise triage system, patients are triaged according to their hemodynamic conditions, COVID-19 related clinical states, and COVID-19 related laboratory findings. Our triage model can lead to more accurate and resource-effective management of trauma patients with potential COVID-19 infection. LEVEL OF EVIDENCE: Level Ⅲ.

11.
East Mediterr Health J ; 26(11): 1339-1346, 2020 Nov 11.
Article in English | MEDLINE | ID: mdl-33226101

ABSTRACT

BACKGROUND: Medical errors frequently occur in health care facilities, jeopardizing patient safety and increasing associated costs. AIMS: This cross-sectional investigation examined the rates of and reasons for non-reporting of medical errors at Nemazee Hospital, Shiraz, Islamic Republic of Iran. METHODS: Self-administered questionnaires were completed by 283 staff members, including physicians, nurses and medical students. One-way analysis of variance, Fisher's least significant difference post hoc, Spearman correlation coefficient and intraclass correlation tests were used for statistical analyses. RESULTS: Almost all (95.8%) participants had observed at least 1 medical error during the previous year, with over half (50.5%) observing 3-10 errors. The preferred method for reporting medical errors among physicians and medical students was verbal and informal (40.3% and 41.8% respectively), while nurses preferred written forms (45.7%). The results indicated significant differences between groups concerning individual and organizational barriers in general, and among all sub-categories (P < 0.001). CONCLUSION: Concerns of legal entanglements and confidentiality issues were recognized as the main barriers to reporting medical errors.


Subject(s)
Attitude of Health Personnel , Medical Errors , Cross-Sectional Studies , Hospitals , Humans , Iran/epidemiology , Prevalence , Surveys and Questionnaires
12.
Am J Infect Control ; 48(12): 1559-1561, 2020 12.
Article in English | MEDLINE | ID: mdl-32798630

ABSTRACT

BACKGROUND: Iranian were advice to wear a mask and not touch their face during COVID-19 restrictions in Iran. METHODS: One-thousand people were observed for 15-30 minutes in public places between April 22 and May 9, 2020. The average number of touches to the mucosal zone was calculated per hour and mask wearers (N = 568) were compared with those not wearing a mask (N = 432). FINDINGS: Ninety-two percent were observed touching their face at least once an hour and averaged 10 (SD 6) touches per hour. Nonmask wearers touched their face significantly more often than mask wearers (11 vs 8 times per hour, P < .001). Nonmask wearers were 1.5 (95%CI OR 1.2-2.0) times more likely to touch their mucosal zone than mask wearers (P < .001). CONCLUSION: Face touching is a common behavior and may have a role in COVID-19 transmission in the absence of hand hygiene. Mask use decrease the frequency of touching the mucosal zone.


Subject(s)
COVID-19/prevention & control , Face/virology , Hand Hygiene , Health Behavior , Touch , Adult , COVID-19/virology , Female , Humans , Iran , Male , SARS-CoV-2
13.
Comput Math Methods Med ; 2020: 7827434, 2020.
Article in English | MEDLINE | ID: mdl-32587630

ABSTRACT

This study presents a novel methodology to investigate the nonparametric estimation of a survival probability under random censoring time using the ranked observations from a Partially Rank-Ordered Set (PROS) sampling design and employs it in a hematological disorder study. The PROS sampling design has numerous applications in medicine, social sciences and ecology where the exact measurement of the sampling units is costly; however, sampling units can be ordered by using judgment ranking or available concomitant information. The general estimation methods are not directly applicable to the case where samples are from rank-based sampling designs, because the sampling units do not meet the identically distributed assumption. We derive asymptotic distribution of a Kaplan-Meier (KM) estimator under PROS sampling design. Finally, we compare the performance of the suggested estimators via several simulation studies and apply the proposed methods to a real data set. The results show that the proposed estimator under rank-based sampling designs outperforms its counterpart in a simple random sample (SRS).


Subject(s)
Kaplan-Meier Estimate , Survival Analysis , Algorithms , Child , Computational Biology , Computer Simulation , Databases, Factual/statistics & numerical data , Hematologic Neoplasms/mortality , Humans , Mathematical Concepts , Models, Statistical , Probability , Sampling Studies , Statistics, Nonparametric
14.
Iran J Kidney Dis ; 14(1): 44-51, 2020 01.
Article in English | MEDLINE | ID: mdl-32156841

ABSTRACT

INTRODUCTION: Understanding the factors affecting the survival of patients undergoing hemodialysis is the mainstay of care in this population. The present study aims at finding these features using novel cure models that discover factors important in both long term and short-term survival of patients undergoing HD. METHODS: Data were retrospectively collected from the database of Shiraz University of Medical Sciences Special Diseases Administration including patients of 34 HD centers during 2011 to 2015. The primary outcome was death. Considering people with no death event as cured, the rest of the patients considered as uncured. To evaluate the factors affecting mortality, we used a mixture cure model (MCM) that model the long-term and short-term survival of patients separately. RESULTS: Of 506 patients, 68.75% of women and 75.0% of men were long-term survivors. The mean (± SD) age of the patients was 57.5 (± 16.5) years and the empirical value of the cure rate was 72.9%. Sex, age, and Kt/Vurea were recognized as important factors in the long-term survival. In other words, lower age, male sex, and Kt/ Vurea ≥ 1.2 significantly increased the odds of being cured. The factors effective in short-term survival were mean corpuscular hemoglobin concentration (MCHC) and serum hemoglobin. The serum hemoglobin between 11 and 12.5 and a high MCHC decreased the risk of death. CONCLUSION: Using cure model survival analysis, it was found that factors affecting the proportion of the patients with long-term survival might be different from those affecting short-term survival.


Subject(s)
Models, Statistical , Renal Dialysis/mortality , Adult , Aged , Female , Humans , Iran/epidemiology , Male , Middle Aged , Retrospective Studies , Risk Factors , Survival Rate
15.
Foot Ankle Surg ; 26(1): 94-97, 2020 Jan.
Article in English | MEDLINE | ID: mdl-30587438

ABSTRACT

BACKGROUND: Sanders classification, based on the number of displaced fractured fragments of posterior facet, can predict the prognosis of calcaneal intraarticular fractures. The aim of the study was assessing not only intraobserver reproducibility and interobserver reliability of Sanders classification but also the agreement between preoperative reported types based on computed tomography (CT) scan and direct observation during the surgery. METHODS: In this cross-sectional study, preoperative CT scans of 100 patients with intra-articular calcaneal fracture operated by a single surgeon were studied by two orthopedic and trauma surgeons (A & B), twice with an interval of three weeks. Their result were compared with each other and with the number of displaced fractured fragments recorded in the operation notes. Quadratic weighted kappa test was used to check the agreement between two observers and between the observers and the surgeon. RESULTS: Intraobserver reproducibility for Sanders classification of intraarticular calcaneal fractures was found to be good to excellent (A1-A2: 0.91 and B1-B2: 0.75). There was a moderate agreement between the two observers (A1-B1: 0.56, A1-B2:0.58, A2-B1:0.48, and A2-B2:0.51). The agreement between reported types of Sanders classification and the number of displaced fractured fragments seen during the surgery was fair (A1-surgeon: 0.27, A2-surgeon: 0.29, B1-surgeon: 0.38, and B2-surgeon: 0.50). CONCLUSIONS: Agreement between Sanders classification and what is real during surgery is fair. Hence, Sanders classification as determined in the widest cut of coronal CT scan extended posteriorly should be cautiously interpreted for surgery.


Subject(s)
Ankle Injuries/classification , Calcaneus/surgery , Fractures, Bone/classification , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Ankle Injuries/diagnosis , Ankle Injuries/surgery , Calcaneus/diagnostic imaging , Cross-Sectional Studies , Female , Fractures, Bone/diagnosis , Fractures, Bone/surgery , Humans , Intraoperative Period , Male , Middle Aged , Prognosis , ROC Curve , Reproducibility of Results , Young Adult
16.
BMC Infect Dis ; 19(1): 1094, 2019 Dec 30.
Article in English | MEDLINE | ID: mdl-31888541

ABSTRACT

BACKGROUND: Human Immunodeficiency Virus (HIV) infection has become a global concern. Determining the factors leading to death among HIV patients helps controlling Acquired Immune Deficiency Syndrome (AIDS) epidemic. Up to now, little is known about mortality and its determinants among people living with HIV in the Middle East and North Africa (MENA) region, including Iran. The purpose of this study was to assess the risk factors of AIDS-Related Mortality (ARM) and Non-AIDS-Related Mortality (NARM) among people with HIV in Iran. METHODS: This 20-year retrospective study was conducted on 1160 people with HIV whose data were collected from 1997 to 2017. The association of the study outcomes (ARM and NARM) with various study variables, including demographic status at the time of diagnosis and clinical indexes during the follow-up were examined to define the predictors of mortality among the patients. Regarding, Cox proportional hazard and competing risk models were fitted and Adjusted Hazard Ratios (AHR), Sub-distribution Hazard Ratio (SHR) and the 95% Confidence Intervals (CI) were reported. RESULTS: during the follow-up period, 391 individuals (33.7%) died with 86,375 person-years of follow-up. Of the total deaths, 251 (64.2%) and 140 (35.8%) were ARM and NARM, respectively. Rates of the mortality caused by AIDS and non-AIDS were 3.2 and 4.5 per 1000 person-months, respectively. Responding to combined Antiretroviral Treatment (cART) 6 months after initiation, receiving Pneumocystis Pneumonia (PCP) prophylaxis, and higher CD4 count at diagnosis, reduced the hazard of ARM and NARM. However, older age, late HIV diagnosis, and last HIV clinical stages increased the hazard of AIDS related to mortality. Additionally, male gender, older age, incarceration history, and last HIV clinical stages increased the non-AIDS mortality. CONCLUSIONS: Mortality caused by AIDS and non-AIDS remains high among people with HIV in Iran, particularly among males and those with late diagnosis. It seems that applying effective strategies to identify infected individuals at earlier stage of the infection, and targeting individuals with higher risk of mortality can decrease the mortality rate among HIV infected people.


Subject(s)
Acquired Immunodeficiency Syndrome/mortality , Acquired Immunodeficiency Syndrome/drug therapy , Adult , Anti-Retroviral Agents/therapeutic use , Antibiotic Prophylaxis , CD4 Lymphocyte Count , Delayed Diagnosis , Female , Follow-Up Studies , Humans , Iran , Male , Middle Aged , Mortality , Pneumonia, Pneumocystis/prevention & control , Proportional Hazards Models , Retrospective Studies , Risk Factors , Treatment Outcome
17.
Med J Islam Repub Iran ; 33: 139, 2019.
Article in English | MEDLINE | ID: mdl-32280645

ABSTRACT

Background: White blood cell (WBC) counts are commonly used for the diagnosis of acute appendicitis in the early stages of pain. However, the effect of certain confounders, particularly age and sex, has been less focused. The purpose of this study was to investigate the diagnostic accuracy of white blood cells in the prediction of acute appendicitis using age-sex-adjusted receiver operating characteristic (ROC) curve. Methods: In this cross sectional study, 131 patients who had undergone appendectomy were studied during 2010-2011. Patients were placed in the normal appendix and acute appendicitis groups. ROC regression was used to identify the effects of the variables of age and sex on the diagnostic accuracy of WBCs using the area under the ROC curve (AUC). Statistical analysis was conducted in Stata 12 software. Results: In ROC regression method, the AUC for the variable of WBC was 0.643 (95% CI: 0.555-0.725) without adjustment for age and sex variables, 0.672 (0.584-0.751) with an age-adjusted variable, 0.698 (0.612-0.775) with a sex-adjusted variable, and 0.710 (0.624-0.786) with both age-sex adjusted variables. Conclusion: Results indicated that age-sex adjusted variables increased the diagnostic accuracy of the WBC test for predicting acute appendicitis using ROC regression method for the WBC test.

18.
Electron Physician ; 10(3): 6540-6547, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29765580

ABSTRACT

BACKGROUND AND AIM: Accurate prediction of prognosis of patients admitted to intensive care units (ICUs) is very important for the clinical management of the patients. The present study aims to identify independent factors affecting death and discharge in ICUs using competing risk modeling. METHODS: This retrospective cohort study was conducted on enrolling 880 patients admitted to emergency ICU in Namazi hospital, Shiraz University of Medical Sciences, Shiraz, Iran during 2013-2015. The data was collected from patients' medical records using a researcher-made checklist by a trained nurse. Competing risk regression models were fitted for the factors affecting the occurrence of death and discharge in ICU. Data analysis was conducted using STATA 13 and R 3.3.3 software. RESULTS: Among these patients, 682 (77.5%) were discharged and 157 (17.8%) died in the ICU. The patients' mean ± SD age was 48.90±19.52 yr. Among the study patients, 45.57% were female and 54.43% were male. In the competing risk model, age (Sub-distribution Hazard Ratio (SHR)) =1.02, 95% CI: 1.007-1.032), maximum heart rate (SHR=1.009, 95% CI: 1.001-1.019), minimum sodium level (SHR=1.035, 95% CI: 1.007-1.064), PH (SHR=7.982, 95% CI: 1.259-50.61), and bilirubin (SHR=1.046, 95% CI: 1.015-1.078) increased the risk of death, while maximum sodium level (SHR=0.946, 95% CI: 0.908-0.986) and maximum HCT (SHR=0.938, 95% CI: 0.882-0.998) reduced the risk of death. CONCLUSION: In conclusion, the results of this study revealed several variables that were effective in ICU length of stay (LOS). The variables that independently influenced time-to-discharge were age, maximum systolic blood pressure, minimum HCT, maximum WBC, and urine output, maximum HCT and Glasgow coma score. The results also showed that age, maximum heart rate, maximum sodium level, PH, urine output, and bilirubin, minimum sodium level and maximum HCT were the predictors of death. Furthermore, our findings indicated that the competing risk model was more appropriate than the Cox model in evaluating the predictive factors associated with the occurrence of death and discharge in patients hospitalized in ICUs. Hence, this model could play an important role in managers' and clinicians' decision-making and improvement of the standard of care in ICUs.

19.
J Emerg Trauma Shock ; 11(1): 38-41, 2018.
Article in English | MEDLINE | ID: mdl-29628667

ABSTRACT

BACKGROUND: Uncontrolled hemorrhage still remains a major cause of trauma-associated mortality. The events resulting in acute traumatic coagulopathy, particularly hypofibrinogenemia, make control of bleeding difficult. It is essential to timely predict, diagnose, and manage trauma-induced coagulopathy. AIMS: The aim of this study is to determine clinical and easily available laboratory variables that are predictive of hypofibrinogenemia in acute trauma patients. SETTINGS AND DESIGN: This 2-year retrospective work examined the data of major trauma patients that were referred to Shahid Rajaee Hospital's emergency room in hemorrhagic shock condition. MATERIALS AND METHODS: Fibrinogen level was assessed for these patients on their arrival at our facility. Along with clinical and routine paraclinical variables, we evaluated the predictive value of these variables for a fibrinogen level below 100 mg/ml. RESULTS: A total of 855 cases were included (females: 16.4%; and males: 83.6%) in the study. The mean ± SD age was 36 ± 17.9 years, and the mean ± SD injury severity score was 12.2 ± 9. Motor vehicle accident was the most common cause of injury. Three factors, including arterial pH (cut off point = 7.34; area under the curve [AUC]: 0.59), base excess (cutoff point = -4.3; AUC: 0.60), and patients' gender had a significant association with the fibrinogen level under 100 mg/ml. When three factors of pH, BE, and patients' gender are being assessed simultaneously, the AUC became 0.62 (the predictive ability improved). CONCLUSIONS: Variables, including arterial pH, BE level, and patients' gender have predictive value for fibrinogen transfusion in trauma.

20.
Asian Pac J Cancer Prev ; 19(3): 749-753, 2018 Mar 27.
Article in English | MEDLINE | ID: mdl-29582630

ABSTRACT

Objective: There are a number of models for determining risk factors for survival of patients with gastric cancer. This study was conducted to select the model showing the best fit with available data. Methods: Cox regression and parametric models (Exponential, Weibull, Gompertz, Log normal, Log logistic and Generalized Gamma) were utilized in unadjusted and adjusted forms to detect factors influencing mortality of patients. Comparisons were made with Akaike Information Criterion (AIC) by using STATA 13 and R 3.1.3 softwares. Results: The results of this study indicated that all parametric models outperform the Cox regression model. The Log normal, Log logistic and Generalized Gamma provided the best performance in terms of AIC values (179.2, 179.4 and 181.1, respectively). On unadjusted analysis, the results of the Cox regression and parametric models indicated stage, grade, largest diameter of metastatic nest, largest diameter of LM, number of involved lymph nodes and the largest ratio of metastatic nests to lymph nodes, to be variables influencing the survival of patients with gastric cancer. On adjusted analysis, according to the best model (log normal), grade was found as the significant variable. Conclusion: The results suggested that all parametric models outperform the Cox model. The log normal model provides the best fit and is a good substitute for Cox regression.


Subject(s)
Factor Analysis, Statistical , Models, Statistical , Stomach Neoplasms/mortality , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Risk Factors , Stomach Neoplasms/pathology , Stomach Neoplasms/therapy , Survival Rate
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