فهرست مطالب mahboobeh rasouli

Hypertension is a health problem. The purpose of the present study was to compare perceived self-efficacy, benefits, and barriers of hypertension control between male and female patients.

This cross-sectional study was carried out on 400 patients referred to Rajaie Cardiovascular Medical and Research Center in Tehran from August 2020 through March 2021. The convenience sampling method was used. The data collection tools consisted of a digital sphygmomanometer, a demographic form, and a researcher-made questionnaire of perceived benefits, barriers, and self-efficacy of hypertension control, whose validity and reliability were obtained.

The mean age of the male and female patients was 54.02±12.93 years and 56.48±12.10 years, respectively. The mean score of perceived barriers in women was lower than that in men, and the mean perceived self-efficacy in women was higher than that in men (P<0.001). According to the regression test, history of smoking in men and family history of hypertension and age in women were predictors of perceived benefits. Further, occupation and history of smoking in men and education level, family history of hypertension, and history of smoking in women were predictors of perceived barriers. Additionally, marital status, education level, and disease duration in men and education level, family history of hypertension, history of smoking, and age in women were predictors of perceived self-efficacy (P<0.050).

In men, the mean score of perceived barriers was higher and the mean score of perceived self-efficacy was lower. Additionally, the predictors of each of these perceptions were determined.

Intellectual disability and specific cognition in down syndrome (DS) affect language development and processing. We assessed vocabulary and syntax reception among children with DS with typically developed (TD) Persian-speaking Iranian children. We also investigated the association between vocabulary and syntax reception in children with DS.

Using the Stanford–Binet intelligence scales test, 18 TD children (4-6 years old) and 18 DS children were matched based on non-verbal mental age. Vocabulary reception was assessed using the receptive picture vocabulary test (RPVT) and syntax reception by the Persian syntax comprehension test.

Mean total vocabulary reception was lower in children with DS (P<0.001). Syntax reception was also impaired in children with DS compared to the normal values of the test. Among children with DS, vocabulary reception was positively correlated with syntax reception. Every unit increase in total vocabulary reception score was associated with 0.08 (95% confidence interval, CI: 0.04-0.12) improvement in syntax score in children with DS.

Vocabulary and syntax reception in DS children, especially complex syntax structures, was impaired. The observed association between vocabulary and syntax reception shows that vocabulary reception improvement might result in progressing syntax reception in children with DS.

Pragmatics refers to how language is used in social communication. Pragmatics has different dimensions. This study investigated the turn-taking, topic maintenance, and duration of topic maintenance in children with Cochlear implants (CIs) and normal-hearing children matched with chronological age and language age.

In this cross-sectional study, pragmatics were compared in 15 CI children, 15 normal-hearing children matched with chronological age, and 15 normal-hearing children matched with language age. Pragmatic skills of subjects such as turn-taking, topic maintenance, and duration of topic maintenance in verbal conversation were observed and measured in two groups including CI children with age-matched peers and CI children with language-matched normal-hearing children. The children’s conversations were transcribed and the data were analyzed based on the normality of their distribution by independent-sample t-test and Mann-Whitney U tests.

Findings showed no significant difference between the mean of turn-taking, topic maintenance, and duration of topic maintenance skills of CI children with their hearing peers (P>0.05). Also, the results obtained by comparing the mean of turn-taking, topic maintenance, and duration of topic maintenance skills in CI children with normal-hearing children matched with language age did not show a significant difference (P>0.05).

Children with CIs achieved a level of skills in turn-taking, topic maintenance, and duration of topic maintenance, which was similar to age-matched and language-matched normal-hearing children. Probably, the duration of auditory experience after cochlear implantation, age of implantation of the prosthesis, age of diagnosis of hearing loss, age of rehabilitation intervention, and family follow-up have been effective in achieving these skills.

 Uncivil behavior in clinical learning environments is a growing challenge that severely disrupts the teaching and learning process.

 The aim of this study is to evaluate the incidence of uncivil behavior in clinical learning environments from the perspective of nursing students in western Iran.

 In this self-report descriptive cross-sectional study in the 2020 year, 135 undergraduate nursing students of semesters 3, 4, 6, and 8, who were taking training and internship courses, were enrolled. The standard UBCNE questionnaire with 20 questions based on the Likert scale and subscales of exclusionary, hostile/rude, and dismissive behaviors constituted research tools. Data were analyzed using SPSS version 21 and descriptive and inferential statistics.

 103 (76.3%) trainees and 32 (23.7%) interns with a mean age of 21.53 years (1.60) participated in this study. According to the results of the Kruskal-Wallis test, the mean scores of hostile/rude, exclusionary, and dismissive behaviors and the total score in different semesters were significantly different (P < 0.001). In terms of the semester, these behaviors had the highest rate in semester 6 students and the lowest in semester 8 students. There was no statistically significant relationship between gender and the mean incidence of these behaviors in students.

 The results show the students’ experience with different behaviors in clinical settings according to different contexts. Further research is required to understand these behaviors in clinical settings better and to provide strategies to minimize such behaviors.

Given the international recognition concerning the importance of digital literacy, and the increasing understanding of its importance in active learning, virtual education has recently attracted a great deal of attention. This method has provided an opportunity for teaching innovation in times of COVID-19. In this study, we aimed to compare the effects of virtual interactive education on improving nurses’ knowledge and performance in neonatal skin care. This quasi-experimental pre-post study was performed on 100 nurses working in the neonatal intensive care units. The participants were divided into three groups, namely the in-person workshop (n=34), virtual interactive education (n=33), and control (n=33). The instruments included Association of Women’s Health, Obstetric, and Neonatal Nurses (AWHONN) standardized questionnaire. The t test, exact fisher, and repeated measures ANCOVA were conducted to analyze the data using SPSS V. 16 software. The results revealed a significant difference between the pre and post test scores of workshop and multimedia groups in terms of the mean score of knowledge compared to the control group (P<0.001). Similarly, there was a significant difference between the pre- and post-test scores of the workshop and multimedia groups concerning the mean score of performance compared to the control group (P<0.001). The mean score of knowledge and performance increased in both multimedia (20.76±1.30) and workshop groups (15.32±1.95) after the intervention, but the mean score in the multimedia group was more than that of the workshop group (P<0.001). According to the results, the virtual multimedia training method could be used as a solution to address the growing demand for training nursing staff provided that we could lay the required foundation and design the right training methods.

Embryo donation, so to speak, is the transfer of the embryo resulting from the extrauterine insemination of the third couple's sperm into the applicant's womb, who for some reason is not capable of reproduction. Mutual respect is spoken, but an important issue such as the confidential relationship that is created as a result of this donation has remained silent, which can cause problems in the future. According to medical theories, the origin of the embryo is egg and sperm, so there is no doubt in assigning the donated embryo to the donor couple, but what is the subject of question and controversy is the relationship that the donated embryo has with the donor couple, or in other words, their biological parents. This article, which is written with a descriptive and analytical method, examines different theories and it is concluded that among the different jurisprudential and medical theories, the theory that the child is basically attributed to the donor couple, but in the case of the donor couple The recipient is in the status of a foster child in relation to the woman who owns the uterus and in the status of her godmother in relation to the husband of the woman who owns the womb; It is the most acceptable theory.

The research method is descriptive-analytical using library resources.

Ethical Considerations: 

In the upcoming research, it has been done by maintaining the originality of the content and respecting the principle of fairness and trustworthiness.

In this article, it can be seen that according to medical theories, the origin of the embryo is the egg and sperm. Therefore, there is no doubt in assigning the donated embryo to the donor couple, but what is the subject of question and dispute is the clarification of the legal position of the parties (donor and recipient) in this legal act and the legal relationship between the donor couple and the donor couple as a result of the legal act of donating the donated embryo. Or, in other words, the parents find their birth certificate, which recognizes the fetus as a gifted object, the one who gives the fetus is the donor and the one who receives the fetus is the one who receives the fetus.

Among the different jurisprudential and medical theories, this theory that basically the child is attributed to the donor couple, but in the case of the donor couple, the woman who owns the womb is considered as a foster child and the husband of the woman who owns the womb is considered as her foster child, among all the theories. This theory is the most acceptable theory.

Congenital heart defects are one of the most common congenital anomalies and delay in their diagnosis causes a significant increase in mortality and complications. The aim of this study was to determine the frequency of congenital heart diseases using pulse oximetry in neonates born in hospitals of Golestan University of Medical Sciences.

In this cross-sectional descriptive study, 357 seemingly healthy infants born from June 2016 to September 2017 in hospitals affiliated to Golestan University of Medical Sciences underwent right hand and foot pulse oximetry. If the oxygen saturation level was less than 94% in the baby's right hand and foot, it was checked again one hour later and if the result was repeated, the baby was referred to a specialist for further testing. Correspondingly, neonates who exhibited positive results underwent a follow up 3 months after the primary pulse oximetry test. Findings were divided into descriptive sections (mean, standard deviation and frequency distribution table) and inferential including multivariate regression analysis then they were analyzed. The significance level was 0.05.

Out of 357 neonates, 341 had an oxygen saturation level above 94%. Among the 16 cases who had a blood oxygen saturation less than 94%, 14 cases exhibited an oxygen saturation level above 94% after a second examination. 2 cases had a saturation level of less than 94%. The results showed that from the 357 infantes both the cases that exhibited lower oxygen saturationhad (0.6%) suffered from mild ASD during the study and after the follow-up carried out after 3 months. There was also a significant and direct relationship between maternal non-smoking (P<0.005), absence of maternal heart disease (P<0.005) and maternal family, no history of maternal abortion (P = 0.005) and number of abortions (P = 0.011), Absence of stillbirth (P<0.005) and number of stillbirths (P<0.005) and absence of serious diseases of diabetes, thyroid and hypertension and having other minor diseases (P<0.005) with neonatal oxygen saturation level.

According to the results of the present study, which showed a significant and direct relationship between maternal variables and neonatal blood oxygen saturation, accurate history and clinical examination along with pulse oximetry can be considered as an important tool to identify congenital heart disease in infants.

Cleft Palate (CP) with or without Cleft Lip (CL/P) are the most common craniofacial birth defects. Cleft Lip and Palate (CLP) can affect children’s communication skills. The present study aimed to evaluate language production skills concerning morphology and syntax (morphosyntactic) in children with CLP.

In the current cross-sectional study, 58 Persian-speaking children (28 children with CLP & 30 children without craniofacial anomalies=non-clefts) participated. Gathering the language samples of the children was conducted using the picture description method. The 50 consecutive intelligible utterances of children were analyzed by the Persian Developmental Sentence Scoring (PDSS), as a clinical morphosyntactic measurement tool.

The PDSS total scores of children with CLP were lower than those of the non-clefts children. A significant difference was found between the studied children with CLP and children without craniofacial anomalies in the mean value of PDSS total scores (P=0.0001). 

Children with CLP demonstrate a poor ability for using morphosyntactic elements. Therefore, it should be considered how children with CLP use the grammatical components.

Voice is influenced by personality. However, it is still questionable which acoustic features are influenced by personality traits. This study aimed to investigate the relationship between acoustic characteristics and personality dimensions.

Thirty-three participants with dysphonia and 33 participants without dysphonia were recruited to take part in this cross-sectional study. Personality dimensions were evaluated by the revised NEO personality inventory, and acoustic characteristics by using the Praat software. The tasks included prolongation of the vowel /a/, expression of declarative and interrogative sentences, reading, and connected speech. The acoustic features included fundamental frequency range, jitter, shimmer, harmonic-to-noise ratio, intensity, and duration. SPSS V. 23 was used for statistical analysis. For correlation analysis, the Pearson and Spearman correlation coefficients were employed.

In individuals with dysphonia, a significant relationship was observed between personality dimensions and the following acoustic features: A. extraversion and intensity in connected speech (P=0.045) and the reading task (P=0.036); B. openness and shimmer in /a/ vowel prolongation (P=0.003); C. openness and the harmonic-to-noise ratio in /a/ the vowel prolongation task (P=0.017); and D. agreeableness and duration in expressing interrogative sentences (P=0.019).

In Persian-speaking participants with and without dysphonia, some acoustic characteristics were significantly correlated with the mean score of the personality test (revised NEO personality inventory). It seems that each voice feature is influenced by personality dimensions. This finding indicates that changes in acoustic characteristics of voice due to personality can be evaluated in laboratory and hearing examinations.

Decades after the introduction of nanotechnology as a new field of research and production, the pace of development of this field has been remarkable. These advances have enabled nanomaterials to be used in various sectors and industries including electronics, optics, consumer goods, energy production and storage, soil and water conservation, as well as in medicine for therapeutic and diagnostic purposes. Worldwide sales of nanomaterials were $ 22.9 billion in 2013 and with annual growth of 19.8%, it is expected to reach US $ 64.2 billion by the end of 2019; Therefore, many economists consider the production and use of nanomaterials an integral part of future economic activities. These advances are due to the unique physico-chemical and biological properties of nanoscale materials. The large surface-to-volume ratio, size and surface characteristics of nanomaterials are the most important physico-chemical properties of them. The specific physico-chemical properties of nanomaterials have led them to show specific behaviors in interaction with biological systems; The most important of these behaviors are moving towards secondary target organs, poor clearance by macrophages, the ability to transmit through the axons of sensory neurons, and to reach intracellular structures such as mitochondria and the nucleus. These properties, in addition to their many applications, have also raised concerns about the potential effects of these substances on human health and the environment. These concerns have generated a large wave of research in the fields of nanomaterials safety, health and toxicology. Forecasts show that the number of staff exposed to nanomaterials will reach about 6 million by the end of 2020. Concerns are increasing day by day as the number of workers exposed to nanomaterials increases. In our country more than 200 companies are active in the field of production and using nanomaterials. These companies have received 517 nanoscale certification for their products, until January 2019. Their products are exported to 49 countries and 5 continents worldwide. The increasing growth of these activities in the country necessitates attention to the safety, health and environmental aspects of nanotechnology. According to what was said, this study aimed to investigate the relationship between the symptoms of employees of nanomaterials producing and consuming companies with chemical composition (as a factor affecting the type and severity of effects) and physical state (as an influencing factor on exposure) of the nanomaterials.

The present study is a descriptive cross-sectional study carried out in 2018 among employees of nanotechnology companies in Tehran. Specifications of the companies were provided by correspondence with the Ministry of Industry, Mine & Trade. Of the companies invited, 52 companies agreed to participate in the study. Staff symptoms were assessed using a nonspecific symptoms questionnaire. The questionnaire was designed and validated in a period of two months by a team of 19 experts in the fields of occupational health, occupational medicine, toxicology, medical nanotechnology and health education. The required information about the occupational characteristics, chemical composition and physical state of the nanomaterials used in the companies was also collected using the NanoTool method form. The questionnaire and the form were then emailed to staff exposed to nanomaterials. Staff inclusion criteria were "to have direct exposure to nanomaterials, that is, to produce or consume nanomaterials during their daily working processes" and "to have at least one year of experience". Of the 52 companies that agreed to participate in the study, 198 completed questionnaires and completed forms were received. Finally, data were analyzed using SPSS.22 software. Frequency distribution tables and Chi-squared test, Fisher exact test and Kruskal-Wallis test were used for this purpose.

The study of the characteristics of the subjects showed that their mean age was 33.76 (SD = 6.108) years; Their average work experience was 6.76 (SD = 5.217) years. Study participants were well educated, with 61.2% having a masterchr('39')s or doctorate degree. 49% (96) of the subjects were men and 51% (100) of them were women. Manufactured / consumed nanomaterials in companies were investigated in similar groups in terms of chemical composition (metal, metal oxide, carbonous and the others) and physical state (dry powder, suspension/ emulsion, paste/gel and the others). The results of investigating the frequency of symptoms of nanotechnology companies’ employees using nonspecific symptoms questionnaire showed that the frequency of some skin symptoms such as "redness", "itching" and "roughness" were 72.7%, 67.2% and 62.6%, respectively. the frequency of some respiratory symptoms were also high; "cough" (64.1%), "sneezing" (60.6%) and "sore throat" (60.1%). High-frequency ocular symptoms included "eye irritation" (66.2%), "itchy eyes" (28.3%), and "red eyes" (25.3%).Investigation of the correlation between the skin symptoms of the employees with the chemical composition and physical state of the nanomaterials used in the companies showed that the symptoms "skin roughness", "skin itching", "skin rash" and "hair loss" have significant correlation with the physical state of nanomaterials and "skin redness", " Skin darkness "and" skin rash" have significant relationship with the chemical composition of nanomaterials. Investigation of the relationship between employeeschr('39') gastrointestinal symptoms with the chemical composition and physical state of the nanomaterials used in the companies showed that the symptoms "appetite suppression", "thirst", "nausea/vomiting" and "darkness of stool color" have significant relationship with the physical state of nanomaterials and "thirst", "Nausea/vomiting" and "inability to detect taste" have significant relationship with the chemical composition of nanomaterials. Evaluation of the relationship between neurological symptoms of staff with the physical state and chemical composition of nanomaterials showed the significant relationship between "movement problems" and chemical composition of nanomaterials. Also, "dizziness" and "sleeplessness/wakefulness" were significantly associated with both the chemical composition and the physical state of the nanomaterials. Investigating the relationship between the chemical composition and physical state of the nanomaterials with the respiratory symptoms of staff revealed "shortness of breath", "wheezing", "chest heaviness", "difficult breathing", "increased phlegm" and "voice change" significantly correlated with Both the chemical composition and the physical state of the nanomaterials. "Cough" was also significantly associated with the chemical composition of the nanomaterials. Examination of the correlation between ophthalmic symptoms and chemical composition and physical state of nanomaterials indicated that the symptoms "blurred vision" and "visual impairment" were significantly correlated with the chemical composition of the nanomaterials. Also, "increased eye gum" and "red eyes" were significantly associated with both the chemical composition and the physical state of the nanomaterials.

Given the frequency of symptoms in staff exposed to nanomaterials, their statistical association with the chemical composition and physical state of nanomaterials, Staffchr('39')s attitude toward nanomaterials that are generally considered safe, inadequate and generally inappropriate use of personal protective equipment appropriate to work with nanomaterials and lack of education and training about the effects of nanomaterials on health and the environment, existing these problems among the employees of these companies are reasonable and that is an important issue. Therefore, the following are suggested to reduce occupational exposure to nanomaterials: Provide adequate training to the staff of these companies in the areas of basic concepts of nanosafety, standard work procedures when working with nanomaterials, appropriate personal protective equipment for working with nanomaterials and using them properly and waste management of nanomaterials.

Anxiety is a common symptom in patients with the Acute Coronary Syndrome (ACS), which can threaten their quality of life. This study was done to compare the effects of aromatherapy using lavender and Benson’s relaxation technique on the anxiety of patients with ACS.

In this randomized clinical trial, 96 patients with ACS were selected using consecutive sampling method from two hospitals in an urban area of Iran. The patients were randomly assigned to three groups of aromatherapy (n=32), Benson’s relaxation (n=32), and control (n=32) using the block size of six. The interventions were performed on two consecutive days, once a day for 20 min. Anxiety was measured before and immediately after the intervention using the Spielberger’s Anxiety Inventory. Data were analyzed using the Chi-square test, Fisher’s exact test, one-way Analysis Of Variance (ANOVA), Bonferroni post hoc test, and mixed-model repeated-measures ANOVA with a 3*2*2 design by the SPSS V. 16.

There was no statistically significant difference in state and trait anxiety scores between the groups after the intervention on different time points (P> 0.05). The time (P=0.001), group-day interaction (P=0.005), and time (pretest and posttest) and day (P=0.029) effect on state anxiety was statistically significant. The time (P<0.001) and the group-day interaction (P<0.001) effect on trait anxiety was statistically significant.

Benson’s relaxation method and lavender aromatherapy did not significantly reduce anxiety in patients with ACS. Considering the anxiety and its complications in patients with ACS and the importance of its management, further studies are needed to determine appropriate care and treatment for these patients and reduce their anxiety.

There is no agreement on how the hands are positioned in cardiopulmonary resuscitation (CPR). In this study, the effects of two methods of positioning the hands during basic and advanced cardiovascular life support on the chest compression depth are compared.

In this observational simulation, the samples included 62 nursing students and emergency medicine students trained in CPR. Each student performed two interventions in both basic and advanced situations on manikins and two positions of dominant hand on non-dominant hand, and vice versa, within four weeks. At each compression, the chest compression depth was numerically expressed in centimeter. Each student was assessed individually and without feedback.

The highest mean chest compression depth was related to Basic Cardiovascular Life Support (BCLS) and the position of the dominant hand on non-dominant hand (5.50 ± 0.6) and (P = 0.04). There was no statistically significant difference in the basic and advanced regression variables in men and women except in the case of Advanced Cardiovascular Life Support (ACLS) with dominant hand on non-dominant hand (P = 0.018). There was no significant difference in mean chest compression during basic and advanced cardiovascular life support in left- and right-handed individuals (P = 0.09).

When the dominant hand is on the non-dominant hand, more pressure with greater depth is applied.

Nowadays, using nanomaterials is provided in various fields of science and technology due to their unique size and characteristics. On the other hand, these unique properties have created many concerns about the potential effects of nanomaterials on human and the environment. Occupational exposure is the most important way of human exposure with nanomaterials. Therefore, this study was conducted to investigate the symptoms of the workers of the nanotechnology companies in Tehran.

At first, a non-specific symptom questionnaire was designed and validated by a group of specialists. Then, nanotechnology companies were identified and questionnaires were provided to the employees of these companies. Finally, the data were analyzed using SPSS.22 software.

The results showed that the designed questionnaire had a good validity and reliability for the study. The average age of employees was less than 34 years and the average working experience was less than 7 years, indicating Newness of nanotechnology in the country. The results showed that the frequency of skin symptoms (such as roughness, itching and redness), respiratory symptoms (such as coughing, sneezing and sore throat) and ocular symptoms (such as burning, itching and redness) are relatively high among the workers of the nanotechnology companies.

Because the results indicated that the frequency of some of the symptoms were high among the workers of the companies under investigation, it is necessary to use control measures to reduce the exposure and contact of the workers with nanomaterial.

Patients with coronary heart diseases need knowledge aboutshould know the risk factors of the disease to manage their illnesses. The aim of This study was aimed to investigate the relationship between knowledge about of coronary heart diseases risk factors and health-promoting lifestyle in adults living in Tabriz City.  This descriptive correlational study was performed conducted on 346 adults above older than 18 years old that were selected by convenience sampling method from public places in Tabriz. The study Data data were collected by a demographic characteristics form, Heart Disease Fact Questionnaire (HDFQ) and Health-Promoting Lifestyle Profile (HPLP) and. Then the obtained data were analyzed by analysis of variance, the Iindependent t-test, the Pearson correlation coefficient, and linear regression analysis using in SPSS V. 22. The knowledge of 57.51% of the participants about coronary heart disease risk factors was goodacceptable. Their Mean±SD score of health- promoting lifestyle was 136.30 ±21.15 (in at a moderate level). Spiritual growth dimension (M=26.8) and exercise and physical activity dimension (M=16.54) had the highest and lowest mean scores, respectively. The results also showed that there is a significant relationship between knowledge of coronary heart diseases risk factors and health-promoting lifestyle (P<0.001). There was a significant relationship between the knowledge of coronary heart disease risk factors with and variables of age, marital status, occupational status, economic status, history of diabetes, and lipid profile (P<0.05); but However, health-promoting lifestyle was only associated with history of diabetes (P=0.03). Performing Educational interventions at different levels of prevention could be suggested to increase the knowledge of these patients about the risk factors of coronary heart disease and hopefully in hope of promoting their people’s lifestyle.

Menopause is the most important event in middle-age. Women, in this period, face several changes. Vasomotor symptoms and skin changes are prevalent in the middle-age. This study, mainly, was performed identifying the vasomotor symptoms and skin changes in menopausal women.

Study sample was consisted of 150 women who have visited the healthcare centers, experienced natural menopause as discontinuity of menstrual at least for 12-monthes. They have been selected randomly. Survey instruments were structured questionnaire, informational records, symptoms and signs checklist, centi-meter and balance and the data collecting method was through interview, observation, and examination. The data were analyzed using logistic regression.

According to study results, skin warming and hotness (55.3%), hands and legs nipping (63.3%), hirsutism of pinion lip (27.3%), reduction of armpit hair (38%), acne (12%), Skin extenuation and wrinkling (51.3%) were reported. The most important point of the study is the significant relationship between amount of tea consumption and flushing severity (P=0.008, OR=3.18). Also, there was a significant relation between education and menopause duration, sleep disorders and severity of flushing, menopause duration and skin collagen reduction (P<0.05).

Skin and vasomotor changes is prevalent in these women. Flushing severity influenced by tea consumption, such that drinking more tea will decrease the flushing, is the start point of more researches in this field.

esophageal cancer is the 8th most common cancer and the 6th leading cause of cancer-related death, worldwide. In Iran, the high incidence rates of this type of cancer have been reported from the Caspian Sea region. This study aimed at assessing the factors affecting survival of patients with esophageal cancer in neighbor provinces around Caspian Sea using parametric and semi-parametric models with univariate gamma frailty model. In this study, we performed a prospective review of 359 patients presenting with esophageal cancer from 1990 to 1991. The data were obtained using the Cancer Registry information existed in Babol research center in Iran. Study participants were followed-up until 2006 for a period of 15 years. Hazard ratio was used to interpret the risk of death. The Akaike Information Criterion (AIC) was considered as a criterion to select the best model(s). Of the 359 patients, 225 (62.7%) were male with a mean age of 60.0 years and 134 (37.3%) were female with a mean age of 55.3 at the time of diagnosis. 1-, 3- and 5-year survival rates after diagnosis were 23%, 15% and 13%, respectively. Comparison between Cox and parametric models of AIC showed that the overall fitting was improved under parametric models. Among parametric models, the log-logistic model with gamma frailty provided better performance than other models. Using this model, we found that gender (p=0.012) and family history of cancer (p= 0.003) were significant predictors. Since the proportionality assumption of the Cox model was not held (p = 0.01), the Cox regression model was not an appropriate choice for analyzing our data. According to our findings, log logistic model with gamma frailty could be considered as a useful statistical model in survival analysis of patients with esophageal cancer rather than Cox and log-normal models.

In survival analysis because are still unknown some of the important factors related to disease, it is too difficult or impossible measure all the appropriate factors and related diseases. Not consider these common unknown risk factors causes dependence among survival times, the results from Cox proportional hazard model and parametric models are not reliable. In this case, we use to confront the above problem of frailty models. The purpose of this study was to examine factors affecting survival of patients with gastric cancer using the log-logistic parametric model with gamma frailty and to compare these results with Cox model. This study includes Information of 110 cases with gastric cancer was collected from Babol cancer registry during 1990 through 1991, who were followed up for a period of 15 years by the year 2006. In order to explore factors affecting survival of patients, Cox model and also parametric model Log-logistic with gamma frailty were examined and the Akaike information criterion (AIC) was considered as a criterion to select the best model (s). For the statistical analysis, the statistical softwares SAS 9.1 and STATA 8.0 were used. All P<0.05 were defined as statistical significance. Sample of subjects encompassed 75.4% men and 24.6% women. The mean age at diagnosis was 60.2 yr for men and 57.5 yr for women. The median survival time reached 8.6 months, and survival rates in 1, 3, and 5 years following diagnosis were 25%, 18%, and 17%, respectively. Multivariate analysis showed that family history of cancer might increase significantly the risk of death from cancer according to Cox and parametric models by including and not including heterogeneity effect. According to AIC criterion and the nature of the data (hazard rate is non-monotonic), parametric model (with and without gamma frailty) had better performance when compared to Cox model. And among, log logistic model with gamma frailty seemed more appropriate. In this model, age and family history of cancer were significant predictors. Results indicated that early preventative care for patients with family history of cancer might be of importance to decrease the risk of death in patients with gastric cancer, and being younger, on the other hand, would cause a potential decline in the corresponding risk of death. According to our findings, based on the Akaike criterion and also the nature of the data (the hazard rate is hump-shaped), log logistic model with gamma frailty could be considered as a useful statistical model in survival analysis of patients with gastric cancer rather than Cox model.