Showing 3 results for Afshari Safavi
A Afshari Safavi , H Kazemzadeh Gharechobogh , M Rezaei,
Volume 11, Issue 3 (Vol 11, No 3 2015)
Abstract
Background and Objectives: Missing data is a big challenge in the research. According to the type of the study and of the variables, different ways have been proposed to work with these data. This study compared five popular imputation approaches in addressing missing data in the questionnaires.
Methods: In this study, 500 questionnaires were used for self-medication in diabetic patients. Missing in the observations was artificially generated by random selection of questions and then deleting them. Five imputation ways included: 1) the mean of the questions, 2) the mean of the person, 3) the mode of the person, 4) linear regression, and 5) EM algorithm. For each method, the mean and standard deviation were compared with imputation. The Spearman correlation coefficient, the percentage of incorrectly classified and kappa statistic were also calculated.
Results: A kappa higher than 0.81 represented almost perfect agreement at 10% missingness. The EM algorithm showed the highest level of agreement with the results of actual data with a Kappa of 0.886. With increasing missingness to 30%, the EM algorithm and the mean of the person showed a rather similar agreement with a Kappa of 0.697 and 0.687, respectively.
Conclusion: In this study, the EM algorithm was the most accurate method for handling missing data in all models. The mean of the person method is easy for handling missing data, especially for most non statisticians.
Sm Hosseini , A Afshari Safavi , A Esmaeil Zade , S Beig Rezaei ,
Volume 13, Issue 2 (Vol.13, No.2, Summer 2017)
Abstract
Background and Objectives: Using the anthropometric indicators of children is one of the ways of monitoring their growth. Because of the racial divisions and levels of health and welfare, comparing these indicators with the global reference is not reasonable; therefore, designing a local reference seems necessary. This study aimed to evaluate the growth indices for boys and girls aged 5 to 18 years old living in Isfahan and to compare the indices with standard values.
Methods: In this cross-sectional study, 53,839 subjects were included. Percentiles of body mass index, height, and weight were calculated using the LMS method in the LMS Light software. After normalization of the growth indices, their mean and standard deviation were calculated for each age group and anthropometric indices curves were plotted versus the 5th, 50th and 95th percentiles of the NCHS reference.
Results: In all age categories, the mean SDS scores of BMI in boys and girls was -0.004 ± 0.029 and 0.014 ± 0.062, respectively, indicating no difference with reference values. However, the 95th percentile of the body mass index for the reference population was consistent with the 90th percentile for the population studied. Also, weight in boys below 13 years of age was higher than the reference line while in girls, weight was always higher than the reference value.
Conclusion: Due to differences in the pattern of growth and also lower anthropometric values, particularly among boys, it seems that a national growth curve can be a better guide for future decisions.
H Tavakoli Ghouchani, A Delshad, Hr Shoraka, H Lashkardoost, A Afshari Safavi , J Rahimi,
Volume 16, Issue 5 (Vol 16, Special Issue 2021)
Abstract
Background and Objectives: The COVID-19 pandemic has led to major health and socioeconomic problems worldwide. This study was conducted to determine the clinical features and health behaviors related to COVID-19 in patients presenting to selected COVID-19 centers of North Khorasan University of Medical Sciences.
Methods: This cross-sectional study was carried out using stratified random sampling in 350 patients presenting to selected COVID-19 centers of North Khorasan University of Medical Sciences in August and September 2020. Demographic and clinical features and the data related to COVID-19 disease were collected using a researcher-made checklist and analyzed with the SPSS 24 software using chi-square test and logistic regression.
Results: Of 350 patients, 200 (57.1%) were male and the rest were female. The PCR test was positive in 72% of the patients. The highest percentage of infection was seen in self-employed subjects and driver, people in the age group 30-50 years, and male subjects. The highest observance of masking, hand washing, and social distancing was related to healthcare staff and the lowest was seen in self-employed people, drivers, and military staff. A history of attending a gas station increased the chance of a positive test by 2.3 times (95% CI: 1.13-4.79).
Conclusion: According to the results, age, gender, occupation and history of presence in crowded places are important determinants of infection and adherence to protocols.
