Basic Principles of Reporting Results of Conventional Statistical Tests in Scientific Biomedical Articles

A scientific article is written to convey information to the reader. The results section is the core component of an article and its objective is to report the findings obtained from statistical analyses for testing hypotheses. For multiple reasons, articles published in medical journals are statistically poor; however, few biomedical journals describe the basics of statistical results presentation to authors. As regards, the writing and presentation of statistical results are as important as statistical results finding. The objective of present article is providing an instruction for reporting the results obtained from data analyses by using some common statistical methods. This article contains two parts: general principles about the structure of results section and basic principles related to how to report descriptive and analytical statistics

Predictors of Exclusive Breastfeeding among Nulliparous Iranian Mothers: Application of the Theory of Planned Behavior

Background Although exclusive breastfeeding (EBF) is highly emphasized by the experts, nulliparous women do not adhere to this behavior at a desirable level. Since it seems that mothers’ beliefs and values play an important role in their adherence to these behaviors, the present study, aimed to perform a careful analysis of the behavior and evaluation of factors associated with the EBF in nulliparous women referring to healthcare centers in Bushehr using theory of planned behavior. Materials and Methods This is a cross-sectional study, which was conducted on 400 nulliparous mothers with children less than six-months who referred to healthcare centers in Bushehr, Iran. Stratified random-sample was used and data were collected using a researcher-made questionnaire and were later analyzed using statistical tests, including Pearson, Spearman, linear regression and logistic regression in SPSS version 22.0 Software. Results The results showed that 62.5% of infants were exclusively breast-fed. Variables such as infant' gender, father's occupation and type of pregnancy were significantly related with EBF behavior. Constructs, including attitude (P< 0. 001, r=0.295), subjective norms (P< 0. 001, r=0.376) and perceived behavioral control (P< 0. 001, r=514) were significantly correlated with the EBF intention. Subjective norms, perceived behavioral control and behavioral intention predicted 13.8% changes in mothers' breastfeeding behavior. Conclusion The theory of planned behavior is an appropriate framework to identify factors associated with the EBF behavior among nulliparous Iranian mothers. Therefore, designing interventions based on this theory seems to have the potential to improve the EBF practice

The efficacy of resveratrol in controlling hypertension: study protocol for a randomized, crossover, double-blinded, placebo-controlled trial

Background: Hypertension is a global health concern for which novel treatment strategies are necessary. The aim of this study is to evaluate the efficacy of resveratrol (trans-3, 5, 4′-trihydroxystilbene, a polyphenol present in grapes) in controlling blood pressure in participants diagnosed with prehypertension and stage 1 hypertension. Methods/design: In a randomized, crossover, double-blinded, placebo-controlled study, 50 participants with prehypertension (diastolic blood pressure and systolic blood pressure, 80–89 mmHg and 120–139 mmHg, respectively) and 50 participants with stage 1 hypertension (diastolic and systolic, 90–99 mmHg and 140–159 mmHg, respectively) will be assigned to receive resveratrol (99 % pure, from Biotivia Longevity Bioceuticals LLC Company, USA, in 500 mg capsules, twice daily for 4 weeks, orally) or placebo (500 mg neutral microcellulose capsules, twice daily for 4 weeks) in a 2 × 2 crossover design (4 weeks treatment—4 weeks washout—4 weeks treatment). The blood pressure of each participant will be recorded (a mean of two times within a 15-minute interval) every week during the study. The participants in the prehypertensive group will not receive any medication, while those in the stage 1 hypertensive group will continue to receive their routine medications during the study. Blood samples will be taken from all groups and examined for various biochemical parameters. Discussion: This trial will help to establish whether resveratrol is an effective antihypertensive agent in prehypertensive and stage 1-hypertensive patients. The trial outcome will provide novel insight into the clinical efficacy of resveratrol and provide valuable information for conducting future clinical studies with resveratrol. Trial registration: Iranian Registry of Clinical Trials, IRCT201407078129N7. Registered on 15 August 2014. Keywords: Resveratrol, Hypertension, Blood pressure, Polyphen

Comparison of the Prevalence of Psychiatric Disorders in Performance-Enhancing Drug Users and Nonuser Bodybuilders

Objective: The present study aimed at comparing the prevalence of major psychiatric disorders including major depressive disorder, bipolar disorder, schizophrenia, and generalized anxiety disorder between performance-enhancing drug users and nonuser bodybuilders. Moreover, the prevalence of major psychiatric disorders in bodybuilders was also reported. Method: In this study, 453 athletes were recruited from Bushehr bodybuilding gyms from February to May 2015. A structured questionnaire was used to collect the participants’ information, including demographic characteristics, sports’ status and performance-enhancing drug use. According to the condition of performance-enhancing drug use, the participants were divided into current users, non-current users, and nonusers. The psychiatric status of the participants was evaluated using DSM-IV diagnostic criteria for major depressive disorder, bipolar disorder, generalized anxiety disorder, and schizophrenia. We also asked about the acute psychotic disturbances after using performance-enhancing drugs, alcohol use, and history of aggressive behavior in bodybuilders. Data were analyzed using one-way analysis of variance and chi-square tests. Results: Prevalence of major depressive disorder, bipolar disorder, schizophrenia, generalized anxiety disorder, and the overall prevalence of psychiatric disorders in the bodybuilders was 19.7%, 3.8%, 1.5%, 16.6%, and 26.7%, respectively. After using performance-enhancing drugs, 33% of the bodybuilders had experienced acute psychological disturbances. There were no significant differences between current, non-current, and nonuser bodybuilding athletes in the measured psychiatric disorders. Conclusion: Prevalence of psychiatric disorders was not significantly different in performance-enhancing drug users and nonusers. Thus, it can be concluded that performance-enhancing drugs do not increase the risk of psychiatric disorders in bodybuilders

The Impact of Multimedia Education on Knowledge and Self-efficacy among Parents of Children with Asthma: A Randomized Clinical Trial

Introduction: Asthma is one of the most common chronic diseases among children, and is considered as a global health problem. According to the guidelines of childhood Asthma, parental education in order to improve their knowledge and self-efficacy should be considered in clinical care. Therefore, this study was performed with the purpose of investigating the influence of multimedia education on knowledge and self-efficacy among parents of children with Asthma. Methods: This study is a clinical trial which was carried out on 50 parents of children with Asthma. Three instruments, i.e. demographic information, assessing knowledge and self-efficacy among parents of children were administrated to collect the required data sets. Reliability and validity of the instruments were assessed and the multimedia education was carried out for the experimental group. Data analysis was done using SPSS 13 and descriptive inferential statistical tests (independent t-test and Mann-Whitney). Results: History of Asthma was present in majority 52% among families of the children and 54% reported smoking in their home. The average scores of knowledge and self-efficacy in the experimental group showed an increase after multimedia education methods, so that there was a statistically significant difference between the experimental and control groups. Conclusion: The results obtained in this study also demonstrate that educating parents through multimedia technology increase their knowledge and self–efficacy in their care of children

Chlamydia pneumoniae and Helicobacter pylori IgG seropositivities are not predictors of osteoporosis‑associated bone loss: a prospective cohort study

The potential link between infection with Chlamydia pneumoniae or Helicobacter pylori and osteoporosis has not been investigated in population-based longitudinal studies. A total of 250 healthy postmenopausal women who participated in a prospective cohort study were evaluated for IgG antibodies directed against C. pneumoniae and H. pylori, osteoprotegerin (OPG), the receptor activator of nuclear factor kappa B ligand (RANKL), CrossLaps, and osteocalcin. Bone mineral density (BMD) was measured at the femoral neck and lumbar spine at baseline and at follow- up 5.8 years later. There were no significant differences in age-adjusted bone turnover markers, OPG, RANKL, the RANKL/OPG ratio, and BMD between the C. pneumoniae and H. pylori IgG seropositive and seronegative subjects (P > 0.05). Neither C. pneumoniae nor H. pylori IgG seropositivity was associated with age-and body mass index-adjusted BMD at the femoral neck and lumbar spine or bone loss at the 5.8-year follow-up. In logistic regression analysis, neither C. pneumoniae nor H. pylori IgG seropositivities predicted incident lumbar or spine osteoporosis 5.8 years later. In conclusion, neither C. pneumoniae nor H. pylori IgG seropositivity was associated with bone turnover markers, the RANKL/OPG ratio, BMD, or bone loss in postmenopausal women. In addition, chronic infection with C. pneumoniae or H. pylori did not predict incident osteoporosis among this group of women

Association of serum uric acid with high-sensitivity C-reactive protein in postmenopausal women.

OBJECTIVES: To explore the independent correlation between serum uric acid and low-grade inflammation (measured by high-sensitivity C-reactive protein, hs-CRP) in postmenopausal women. METHODS: A total of 378 healthy Iranian postmenopausal women were randomly selected in a population-based study. Circulating hs-CRP levels were measured by highly specific enzyme-linked immunosorbent assay method and an enzymatic calorimetric method was used to measure serum levels of uric acid. Pearson correlation coefficient, multiple linear regression and logistic regression models were used to analyze the association between uric acid and hs-CRP levels. RESULTS: A statistically significant correlation was seen between serum levels of uric acid and log-transformed circulating hs-CRP (r = 0.25, p < 0.001). After adjustment for age and cardiovascular risk factors (according to NCEP ATP III criteria), circulating hs-CRP levels were significantly associated with serum uric acid levels (β = 0.20, p < 0.001). After adjustment for age and cardiovascular risk factors, hs-CRP levels ≥3 mg/l were significantly associated with higher uric acid levels (odds ratio =1.52, 95% confidence interval 1.18-1.96). CONCLUSION: Higher serum uric acid levels were positively and independently associated with circulating hs-CRP in healthy postmenopausal women. KEYWORDS: C-reactive protein; Uric acid; inflammation; postmenopaus

A Pooled Analysis of Diagnostic Value of 99mTc-Ubiquicidin (UBI) Scintigraphy in Detection of an Infectious Process

Purpose: Although the data are promising fromlimited studies with technetium- 99m ubiquicidin (99mTc-UBI) scintigraphy in detection of infection in humans, these studies have had a limited sample size. This study was conducted to provide a systematic review and meta-analysis of the reported diagnostic accuracy of 99mTc-UBI scintigraphy in detection of an infectious process. Materials and Methods: The PubMed/MEDLINE,Web of Science, EMBASE, and Google Scholar literature databases were systematically searched to find the relevant human studies on 99mTc-UBI scintigraphy. For each eligible study, the truepositive, false-positive, true-negative, and false-negative findings at 99mTc-UBI scintigraphy were recorded, and the overall statistical parameters were acquired. Result: Ten studies carried out from 2004 to 2010 were included in the analysis. The pooled data sensitivity was 94.5 % and with a 95% confidence interval of 91.2%Y96.8%. The pooled specificity was still as high as about 92.7%. The range of reported specificity was from 80% to 100%. The overall accuracy was 93.7% (95% CI: 91.2%Y95.7%). Conclusion: The study demonstrated that 99mTc-UBI scintigraphy can be used to identify an infectious process with admirable accuracy in early views; however, further investigations are recommended