Vitamin D is a cofactor responsible for autoimmune disorders. There is no agreement in the studies investigating the association between vitamin D and fibromyalgia. This study aims to combine the conflicting results of the primary studies which compared these patients with control groups regarding the serum concentration of vitamin D. This meta-analysis has been designed based on PRISMA guidelines. Relevant keywords were searched in PubMed, Science direct, Scopus, Cochrane, and Google scholar and primary studies were selected. After screening the eligible studies according to inclusion/exclusion criteria, we investigated the risk of bias in the selected studies and also the heterogeneity between the primary results using Cochrane (Q) and I-squared (I2) indices. The primary results were combined using inverse variance method and Cohen statistics as well as a random effects model. Publication bias was assessed using Egger test. Sensitivity analysis was applied to investigate the influence of each primary study on the final result of the meta-analysis. Suspected factors in the heterogeneity were assessed using meta-regression models. We entered 12 eligible studies in the meta-analysis including 851 cases compared with 862 controls. The standardized mean difference of Vitamin D between the two groups was −0.56 (95% confidence interval: −1.05, −0.08). Our meta-analysis showed that vitamin D serum levels of patients with fibromyalgia was significantly lower than that of control group.
Bias (Epidemiology) ; Eligibility Determination ; Fibromyalgia* ; Humans ; Mass Screening ; Methods ; Myofascial Pain Syndromes ; Population Characteristics ; Publication Bias ; Vitamin D* ; Vitamins*

OBJECTIVES: Different factors are responsible for the silent epidemic of diabetes mellitus in developing and developed countries. This study aimed to determine the role of demographic factors, lipid profile, family history (the estimation of genetic association) and anthropometric factors on diabetes onset. METHODS: Data from the enrolment phase of the Tabari Cohort study was applied for this study and included 10,255 participants aged between 35–70 years. Anthropometric variables were measured by trained staff using standard tools. Blood specimens were collected for lipid profile and blood glucose measurements. Data analyses were performed using SPSS version 24, with univariate and multivariate logistic regression. RESULTS: The prevalence of diabetes mellitus was estimated to be 17.2% in the cohort population, 15.6% in men, and 18.3% in women. The adjusted odds ratios (95% confidence intervals) for age groups 40–49, 50–59 and over 60 were 2.58 (2.20–3.69), 5.80 (4.51–7.48) and 8.72 (6.67–11.39), respectively. In addition, the odds ratios (95% confidence intervals) for 2 (or more), and 1 affected family member were 4.12 (3.55–4.90) and 2.34 (2.07–2.65), respectively. Triglyceride concentrations more than 500, and abnormal high-density lipoprotein levels increased the odds of diabetes mellitus by 3.29- and 1.18-fold, respectively. CONCLUSION: The current study showed that old age and a family history were strong predictors for diabetes mellitus.
Blood Glucose ; Body Mass Index ; Cohort Studies ; Demography ; Developed Countries ; Diabetes Mellitus ; Female ; Humans ; Lipoproteins ; Logistic Models ; Male ; Odds Ratio ; Prevalence ; Statistics as Topic ; Triglycerides

OBJECTIVES: Enterobius vermicularis is a parasitic disease that is common in crowded areas such as schools and kindergartens. Primary investigations of electronic evidence have reported different prevalences of E. vermicularis in Iran. Therefore, we aimed to estimate the total prevalence of this infection among Iranian children using a meta-analysis. METHODS: Relevant studies were identified in national and international databases. We selected eligible papers for meta-analysis after investigating titles, abstracts, and full texts; assessing study quality; and applying inclusion/exclusion criteria. Data were extracted by two independent researchers. The results were combined using a random effects model in Stata v. 11 software. RESULTS: Among 19 eligible articles including 11,676 participants, the prevalences of E. vermicularis among all children, boys, and girls were 1.2%–66.1%, 2.3%–65.5%, and 1.7%–65.5%, respectively. Pooled prevalences (95% confidence interval) of E. vermicularis among all children, boys, and girls were 17.2% (12.6%–21.8%), 17.2% (12.6%–21.8%), and 16.9% (9.03%–24.8%), respectively. CONCLUSION: This meta-analysis showed that a great majority of Iranian children are infected with E. vermicularis, possibly due to poor public health.
Child* ; Enterobius* ; Female ; Humans ; Iran* ; Parasitic Diseases ; Prevalence* ; Public Health

OBJECTIVES: Tuberculin skin reaction size is one indicator of bacillus Calmette-Guérin (BCG) vaccine efficacy and a way to diagnose latent infection. Several primary studies have examined this issue. Combining the results of these studies using a meta-analysis will provide reliable evidence regarding this indicator for policymakers. This study aimed to estimate the total frequency of different tuberculin skin test reactions among Iranian children and teenagers who received the BCG vaccination at birth. METHODS: National and international databanks were searched using relevant keywords. After the search strategy was restricted and duplicates were excluded, the titles and abstracts of the remaining papers were screened. All included studies included healthy children who received the BCG vaccine without confirmed tuberculosis exposure. Heterogeneity of the results was assessed using the Cochrane test and I² index showed the random effects model as the best model for estimating the pooled results. RESULTS: We combined the results of 14 primary studies including purified protein derivative reaction test measures of 26,281 Iranian children. The frequencies (95% confidence intervals) of the reactions were 8.5% (6.2–10.8) for patients with a reaction size ≥ 10 mm, 29.9% (22.3–37.4) for a reaction size of 5–9 mm, and 60% (48.9–71.1) for a reaction size < 5 mm. CONCLUSION: Our study showed that large numbers of Iranian children and teens have no positive BCG vaccine reaction and a considerable number of children have been exposed to Mycobacterium tuberculosis.
Adolescent* ; Bacillus* ; BCG Vaccine ; Child* ; Humans ; Mycobacterium bovis ; Mycobacterium tuberculosis ; Parturition* ; Population Characteristics ; Skin Tests* ; Skin* ; Tuberculin* ; Tuberculosis ; Vaccination*

OBJECTIVES:: Investigating the survival of patients with cancer is vitally necessary for controlling the disease and for assessing treatment methods. This study aimed to compare various statistical models of survival and to determine the survival rate and its related factors among patients suffering from lung cancer. METHODS:: In this retrospective cohort, the cumulative survival rate, median survival time, and factors associated with the survival of lung cancer patients were estimated using Cox, Weibull, exponential, and Gompertz regression models. Kaplan-Meier tables and the log-rank test were also used to analyze the survival of patients in different subgroups. RESULTS:: Of 102 patients with lung cancer, 74.5% were male. During the follow-up period, 80.4% died. The incidence rate of death among patients was estimated as 3.9 (95% confidence [CI], 3.1 to 4.8) per 100 person-months. The 5-year survival rate for all patients, males, females, patients with non-small cell lung carcinoma (NSCLC), and patients with small cell lung carcinoma (SCLC) was 17%, 13%, 29%, 21%, and 0%, respectively. The median survival time for all patients, males, females, those with NSCLC, and those with SCLC was 12.7 months, 12.0 months, 16.0 months, 16.0 months, and 6.0 months, respectively. Multivariate analyses indicated that the hazard ratios (95% CIs) for male sex, age, and SCLC were 0.56 (0.33 to 0.93), 1.03 (1.01 to 1.05), and 2.91 (1.71 to 4.95), respectively. CONCLUSIONS:: Our results showed that the exponential model was the most precise. This model identified age, sex, and type of cancer as factors that predicted survival in patients with lung cancer.
Cohort Studies ; Female ; Follow-Up Studies ; Humans ; Incidence ; Iran ; Lung Neoplasms ; Lung ; Male ; Models, Statistical ; Multivariate Analysis ; Retrospective Studies ; Small Cell Lung Carcinoma ; Survival Rate

OBJECTIVES: : Investigating the survival of patients with cancer is vitally necessary for controlling the disease and for assessing treatment methods. This study aimed to compare various statistical models of survival and to determine the survival rate and its related factors among patients suffering from lung cancer. METHODS: : In this retrospective cohort, the cumulative survival rate, median survival time, and factors associated with the survival of lung cancer patients were estimated using Cox, Weibull, exponential, and Gompertz regression models. Kaplan-Meier tables and the log-rank test were also used to analyze the survival of patients in different subgroups. RESULTS: : Of 102 patients with lung cancer, 74.5% were male. During the follow-up period, 80.4% died. The incidence rate of death among patients was estimated as 3.9 (95% confidence [CI], 3.1 to 4.8) per 100 person-months. The 5-year survival rate for all patients, males, females, patients with non-small cell lung carcinoma (NSCLC), and patients with small cell lung carcinoma (SCLC) was 17%, 13%, 29%, 21%, and 0%, respectively. The median survival time for all patients, males, females, those with NSCLC, and those with SCLC was 12.7 months, 12.0 months, 16.0 months, 16.0 months, and 6.0 months, respectively. Multivariate analyses indicated that the hazard ratios (95% CIs) for male sex, age, and SCLC were 0.56 (0.33 to 0.93), 1.03 (1.01 to 1.05), and 2.91 (1.71 to 4.95), respectively. CONCLUSIONS : Our results showed that the exponential model was the most precise. This model identified age, sex, and type of cancer as factors that predicted survival in patients with lung cancer.