Social network size estimation and determinants in Tehran province residents

Network scale-up is an indirect method for estimating the size of hidden, hard-to-count or high risk populations. Social network size estimation is the first step in this method. The present study was conducted with the purpose of estimating the social network size of the Tehran Province residents and its determinants. Maximum Likelihood Estimation was applied to estimate people's network sizes by using populations of known sizes and the scale-up method. Respondents were selected from Tehran province through convenience sampling in 2012. Out of thirteen selected subpopulations with known size, ten had minimum accuracy which used in our analysis. Of the 1029 respondents in this study, 46.7% were male. The social network size of Tehran Province residents was estimated to be 259.1 [CI[95%]: 242.2, 276] based on the ten known populations remained in this study. This size was 291.8 in men and 230.4 in women. Younger people [18-25 years old] had larger network sizes compared to the other age groups [P<0.001]. Our estimation for social network size of Tehran inhabitants was smaller than that previously estimated size for the whole country [c=380]. In addition, we found that the social network of subpopulations was different. This difference means that we need local estimations for sub-populations to improve the accuracy of population size estimation using network scale up method

Comparing the effects of group and home-based physical activity on mental health in the elderly

The present study focuses on comparing the effects of home based [HB] and group based [GB] physical activity on mental health in a sample of older adults in Shahr-e-kord. In this quasi-experimental study, a twice weekly physical activity program for 2 months was provided either individually at home or in a group format for 181 people who were divided into two groups [HB and GB]. The outcome, mental health, was measured with the 28 item General Health Questionnaire [GHQ 28]. Mental health status improved after participation in the physical activity program. The decrease in GHQ 28 total score in GB group, 3 months after intervention, was 3.61 +/- 2.28 [P < 0.001]. In HB group, this reduction was 1.20 +/- 2.32 during the same period [P < 0.001]. The difference of these "before-after differences" between the two groups in the GHQ 28 and all its subscales was statistically significant [P < 0.001]. Also, the effects of GB physical activity on mental health compared with HB physical activity, adjusted for related baseline variables, were significant. These findings reveal the probable effects of GB rather than HB physical activity on mental health among the elderly.

Important risk factors of mortality among children aged 1-59 months in rural areas of Shahroud, Iran: a community-based nested case-control study

The aim of the study was to evaluate potential risk factors of children mortality between 1-59 months of age. This nested case-control study was conducted among children born from June 1999 to March 2009 in rural areas of Shahroud, located in the central region of Iran using health care visit reports and follow-up data available in household health records. Mortality was significantly associated with breastfeeding duration [OR: 0.87, 95% CI: 0.81-0.93], total health care visits [OR: 0.90, 95% CI: 0.83-0.98] and low birth weight [LBW] [OR: 7.38, 95% CI: 1.37-39.67]. In our study, a longer breastfeeding period and more frequent health care visits were two important protective factors, while LBW was an important risk factor for 1-59 month child mortality. It seems, that complex and multiple factors may be involved in mortality of under 5-year-old children, so combined efforts would be necessary to improve child health indicators