Hossein Rahbar - Academia.edu (original) (raw)
Papers by Hossein Rahbar
African Journal of Microbiology Research, 2009
Extrapulmonary tuberculosis is one of the major problems in clinical practice. The aim of this st... more Extrapulmonary tuberculosis is one of the major problems in clinical practice. The aim of this study was to evaluate the rate of all diagnosed tuberculosis cases among those urban patients referred to private clinical laboratories, and comparing the results of PCR technique with traditional methods. In the present study, we examined 2123 specimens who were referred from private clinical laboratories between 2006 till 2008. All specimens were stained for acid fast bacilli, cultured with standard procedures and tested with PCR using signal based method after ensuring of nucleic acid purification. One hundred and thirteen patients were positive for TB, pulmonary tuberculosis were proved in 48 patients whilst the remaining 65 cases were classified as extrapulmonary tuberculosis. Positive rates for PCR, culture and staining were 41, 23 and 12 respectively. The respective figures for extrapulmonary tuberculosis were 46, 26 and 14. This study demonstrates that PCR has a high sensitivity in diagnosis of TB than traditional method.
Health Policy and Planning, 1999
Social Science and Medicine, Apr 7, 2015
To explore traditional neonatal beliefs and care practices and to assess the predictors for givin... more To explore traditional neonatal beliefs and care practices and to assess the predictors for giving prelacteal feeds, a qualitative and quantitative study was conducted in low socioeconomic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth semi-structured interviews were conducted in July and August 2000; structured questionnaires were administered to 525 recently delivered women through November.
![Research paper thumbnail of Elevated blood lead levels in Karachi children [letter]](https://attachments.academia-assets.com/48477525/thumbnails/1.jpg)
](Bulletin of the World Health Organization, May 8, 2015
Iranian Journal of Public Health, 2005
Tuberculose has increased in the recent years. Use of a sensitive screening method, can be one of... more Tuberculose has increased in the recent years. Use of a sensitive screening method, can be one of the influential parameters in reduction of pulmonary tuberculosis. Current screening method in the laboratories is based on observation of bacilli in stained smear by Ziel-Neelsen procedure. The aim of this research was to study the PCR efficiency in all confirmed patients of Hamadan province. Twenty eight patients were registered as having pulmonary tuberculosis by the tuberculosis comity of the Hamadan province. All these patients had positive results for staining and culture. Amonst these registered patients, we could access only to the 12 patients during the study. Sputums were collected from early stage of diagnosis and continued during treatment at the end of each month. All these patients were under the treatment by the DOTs protocols. All samples were tested by PCR and the results were compared with Ziehl-Neelsen staining method that is recommended procedure by WHO. Compared results showed none of the samples were positive by staining method at the end of second month up to the last month of treatment, while PCR changed to negative gradually. It was negative in 5 and 4 patients at the end of the third and forth month, respectively. Specimens of the three remanied patients were continuously positive up to the end of treatment period. Gradually changing PCR results to negative in three forth of studied patients means it can be applicable screening tools, but one forth remained positive cases needs more study for the evaluation of target gene role and efficiency of the test.
The aim of this study was to determine the prevalence of methicillin resistant S. aureus (MRSA), ... more The aim of this study was to determine the prevalence of methicillin resistant S. aureus (MRSA), vancomycin resistant or vancomycin intermediate resistant S. aurues (aureus) (VRSA/VISA) among clinical isolates. Study Design: S.aureus isolates used in this study were randomly collected from in-patient and outpatient of several hospitals of 7 cities in Iran (Tehran, Shiraz, Zahedan, Tabriz, Sannandaj, Sari, and Ahvaz) during 2006-2008. Methodology: Antibiotic susceptibility of 250 strains of Staphylococcus aureus isolated from Iranian hospitals were determined by disk diffusion method. Minimum inhibitory concentration (MICs) were determined for oxacillin and vancomycin by E-test. PCRs were used by specific primers (PCR used specific primers) for detection of mecA, vanA, vanB genes. Results: The percentage of resistance by disk diffusion method was as below: methicillin 46%, vancomycin 0%, penicillin 86%, erythromycin 42%, ciprofloxacin 29%, gentamicin 39% and clindamycin 33%. E-test MIC method showed that 43% isolates were resistant to British Microbiology Research Journal, 4(4): 454-461, 2014 455 methicillin and 4% isolates were VISA (≤ 8µg/ml). The prevalence of resistance genes in the clinical isolates were: mecA 44%, vanA 0%, vanB 0%. Conclusion: This study revealed that clinical isolates have rather high resistance to methicillin, erythromycin, gentamicin, penicillin and clindamycin We did not observe resistance to vancomycin. In order to avoid a possible outbreak involving VISA), vancomycin should be used carefully as a drug for treatment of S. aureus infections.
International Journal of Antimicrobial Agents, Feb 1, 2008
Iranian Journal of Parasitology, 2007
of urinary tract infections (UTIs) in hospitalized patients. The aim of this study was to determi... more of urinary tract infections (UTIs) in hospitalized patients. The aim of this study was to determine prevalence of UTI caused by VRE in an Iranian 1000-bed hospital and to assess the activity of commonly used antibiotics including nitrofurantoin against VRE isolates.
Social Science Medicine, Mar 31, 2008
Underlying maternal vascular disease has been implicated as one of several pathways contributing ... more Underlying maternal vascular disease has been implicated as one of several pathways contributing to preterm delivery (PTD) and psychosocial factors such as hostility, anomie, effortful coping, and mastery may be associated with PTD by affecting maternal vascular health. Using data from the Pregnancy Outcomes and Community Health (POUCH) study, we included 2,018 non-Hispanic White and 743 African American women from 52 clinics in 5 Michigan, USA communities who were interviewed at 15−27 weeks' gestation and followed to delivery. We found that relations between psychosocial factors and PTD subtypes (i.e. medically indicated, premature rupture of membranes, spontaneous labor) varied by race/ethnicity and socioeconomic position (Medicaid insurance status). Among African American women not insured by Medicaid, anomie levels in midpregnancy were positively associated with medically indicated PTD after adjusting for maternal age and education. Among all women not insured by Medicaid, hostility levels were positively associated with spontaneous PTD after adjusting for maternal race/ethnicity, age, and education. Failure to detect links between psychosocial factors and PTD risk in poorer women may be due to their excess risk in multiple PTD pathways and/or a more complex web of contributing risk factors.
The wide use of subway system by citizens underlines the importance of hygienic issues including ... more The wide use of subway system by citizens underlines the importance of hygienic issues including indoor air pollution in these public places especially in metro stations. The aim of this study was to investigate the bacterial contamination in indoor and outdoor air of two metro stations (Imam Khomeini and Sadeghiyeh stations) in Tehran subway system. In this cross sectional study, three sampling locations were selected in each station. Also, sampling was conducted in indoor air of two types (old and new) of trains. The range of bacterial colony count was 35-1501 CFU/m 3 . Maximum and minimum bacterial contamination levels in Imam Khomeini and Sadeghiyeh platform stations were averagely 1073 CFU/m 3 and 242 CFU/m 3 , respectively. 14 bacterial species and genera were isolated; among them the dominant species were Staphylococcus epidermidis, Micrococcus luteus and Bacillus spp. Results showed that bacterial concentrations in indoor air were higher than the outdoor air; also the bacterial counts correlated significantly with number of the passengers (p<0.001) and air temperature (p<0.001).
Http Dx Doi Org 10 1080 10543406 2013 789884, Jun 20, 2013
In this article, we discuss an approach for optimal sample size allocation in designing multicent... more In this article, we discuss an approach for optimal sample size allocation in designing multicenter clinical trials. The method we studied was adapted from a stratified sampling survey design. The sample size allocated to centers is a function of the center&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s treatment cost, the standard deviation of the endpoint, and the availability of patients. We illustrate our approach using two hypothetical scenarios derived from our experiences in designing and conducting multicenter clinical trials. Simulation results are also presented.
Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health o... more Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health of children. Previous studies from Jamaica reported that mean lead levels in soil are four times that of lead levels in some other parts of the world. Other studies detected lead levels in fruits and root vegetables, which were grown in areas with lead contaminated soil. In this study, we investigate environmental factors associated with blood lead concentrations in Jamaican children. The participants in this study comprised 125 typically developing (TD) children (ages 2-8 years) who served as controls in an age- and sex-matched case-control study that enrolled children from 2009-2012 in Jamaica. We administered a questionnaire to assess demographic and socioeconomic information as well as potential exposures to lead through food. Using General Linear Models (GLMs), we identified factors associated with blood lead concentrations in Jamaican children. The geometric mean blood lead concentration (GMBLC) in the sample of children in this study was 2.80 μg dL(-1). In univariable GLM analyses, GMBLC was higher for children whose parents did not have education beyond high school compared to those whose parents had attained this level (3.00 μg dL(-1) vs. 2.31 μg dL(-1); P = 0.05), children living near a high traffic road compared to those who did not (3.43 μg dL(-1) vs. 2.52 μg dL(-1); P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), and children who reported eating ackee compared to those who did not eat this fruit (2.89 μg dL(-1) vs. 1.65 μg dL(-1); P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). In multivariable analysis, living near a high traffic road was identified as an independent risk factor for higher adjusted GMBLC (3.05 μg dL(-1) vs. 2.19 μg dL(-1); P = 0.01). While our findings indicate that GMBLC in Jamaican children has dropped by at least 62% during the past two decades, children living in Jamaica still have GMBLC that is twice that of children in more developed countries. In addition, we have identified significant risk factors for higher blood lead concentrations in Jamaican children. We believe increasing awareness among parents regarding these risk factors could potentially lead to a lower level of lead exposure in Jamaican children.
This article presents the results of a systematic literature review to locate peer-reviewed journ... more This article presents the results of a systematic literature review to locate peer-reviewed journal articles that offer equivalent or absorbed radiation dose measurements for locations in outer space.
Bulletin of the World Health Organization, 2002
To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to i... more To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity we...
Social Science & Medicine, 2004
To explore traditional beliefs and practices, to assess puerperal morbidity, and to understand ca... more To explore traditional beliefs and practices, to assess puerperal morbidity, and to understand care-seeking behaviors, a qualitative and quantitative study was conducted in low socio-economic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth interviews were conducted in July and August 2000. 525 Muslim women, who were 6-8 weeks post-partum, were then interviewed at home. Maternal care was relatively good-more than three-quarters of recent mothers sought antenatal care and more than half (267/525) delivered in a hospital or maternity home. Counseling to attend post-partum clinics among facility deliveries was 16% (43/267), of which only 26% (11/43) attended. Practices during the delivery and puerperium, such as massaging the vaginal walls with mustard oil during labor to facilitate delivery and inserting vaginal or rectal herbal pessaries to facilitate 'shrinkage of the uterus' and/or 'strengthening of the backbone', were pervasive.
Social Science & Medicine, 2005
To explore traditional neonatal beliefs and care practices and to assess the predictors for givin... more To explore traditional neonatal beliefs and care practices and to assess the predictors for giving prelacteal feeds, a qualitative and quantitative study was conducted in low socioeconomic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth semi-structured interviews were conducted in July and August 2000; structured questionnaires were administered to 525 recently delivered women through November.
Maternal and Child Health Journal, 2006
To examine the prevalence of depressive symptoms in mid-pregnancy and their relation to life circ... more To examine the prevalence of depressive symptoms in mid-pregnancy and their relation to life circumstances across the life course in a community-based sample. The Pregnancy Outcomes and Community Health (POUCH) Study enrolled women at 16-26 weeks&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; gestation from 52 clinics in five Michigan communities. At enrollment women completed a screening instrument for depressive symptoms (CES-D) and questions about life circumstances covering three &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;periods,&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; i.e. previous 6 months, adulthood, and childhood. Questions were grouped into sub-constructs (e.g., abuse, economic, substance use, loss, and legal) for each &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;period&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; and evaluated in relation to CES-D scores. Analyses included 1321 POUCH participants divided into three subgroups: teens; women &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =20 years insured by Medicaid (disadvantaged); and women &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =20 years not insured by Medicaid (advantaged). A positive CES-D screen (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =16) was more common in teens (46%) and disadvantaged women (47%) than in advantaged women (23%). Recent problems (previous 6 months) with abuse, economics, and substance use in someone close were each associated with higher adjusted mean CES-D scores (2.3-7.5 increase) in the three subgroups of women. In life course analyses, abuse and substance use in teens, and abuse and economic problems in disadvantaged and advantaged women were strongly linked to higher adjusted mean CES-D scores when these problems occurred both in childhood and adulthood (range 2.2-7.1 increase), whereas the associations were more modest when problems were confined to childhood. Strategies for addressing the public health problem of depressive symptoms in mid-pregnancy will benefit from a life course perspective.
Journal of the American Geriatrics Society, 2000
African Journal of Microbiology Research, 2009
Extrapulmonary tuberculosis is one of the major problems in clinical practice. The aim of this st... more Extrapulmonary tuberculosis is one of the major problems in clinical practice. The aim of this study was to evaluate the rate of all diagnosed tuberculosis cases among those urban patients referred to private clinical laboratories, and comparing the results of PCR technique with traditional methods. In the present study, we examined 2123 specimens who were referred from private clinical laboratories between 2006 till 2008. All specimens were stained for acid fast bacilli, cultured with standard procedures and tested with PCR using signal based method after ensuring of nucleic acid purification. One hundred and thirteen patients were positive for TB, pulmonary tuberculosis were proved in 48 patients whilst the remaining 65 cases were classified as extrapulmonary tuberculosis. Positive rates for PCR, culture and staining were 41, 23 and 12 respectively. The respective figures for extrapulmonary tuberculosis were 46, 26 and 14. This study demonstrates that PCR has a high sensitivity in diagnosis of TB than traditional method.
Health Policy and Planning, 1999
Social Science and Medicine, Apr 7, 2015
To explore traditional neonatal beliefs and care practices and to assess the predictors for givin... more To explore traditional neonatal beliefs and care practices and to assess the predictors for giving prelacteal feeds, a qualitative and quantitative study was conducted in low socioeconomic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth semi-structured interviews were conducted in July and August 2000; structured questionnaires were administered to 525 recently delivered women through November.
Bulletin of the World Health Organization, May 8, 2015
Iranian Journal of Public Health, 2005
Tuberculose has increased in the recent years. Use of a sensitive screening method, can be one of... more Tuberculose has increased in the recent years. Use of a sensitive screening method, can be one of the influential parameters in reduction of pulmonary tuberculosis. Current screening method in the laboratories is based on observation of bacilli in stained smear by Ziel-Neelsen procedure. The aim of this research was to study the PCR efficiency in all confirmed patients of Hamadan province. Twenty eight patients were registered as having pulmonary tuberculosis by the tuberculosis comity of the Hamadan province. All these patients had positive results for staining and culture. Amonst these registered patients, we could access only to the 12 patients during the study. Sputums were collected from early stage of diagnosis and continued during treatment at the end of each month. All these patients were under the treatment by the DOTs protocols. All samples were tested by PCR and the results were compared with Ziehl-Neelsen staining method that is recommended procedure by WHO. Compared results showed none of the samples were positive by staining method at the end of second month up to the last month of treatment, while PCR changed to negative gradually. It was negative in 5 and 4 patients at the end of the third and forth month, respectively. Specimens of the three remanied patients were continuously positive up to the end of treatment period. Gradually changing PCR results to negative in three forth of studied patients means it can be applicable screening tools, but one forth remained positive cases needs more study for the evaluation of target gene role and efficiency of the test.
The aim of this study was to determine the prevalence of methicillin resistant S. aureus (MRSA), ... more The aim of this study was to determine the prevalence of methicillin resistant S. aureus (MRSA), vancomycin resistant or vancomycin intermediate resistant S. aurues (aureus) (VRSA/VISA) among clinical isolates. Study Design: S.aureus isolates used in this study were randomly collected from in-patient and outpatient of several hospitals of 7 cities in Iran (Tehran, Shiraz, Zahedan, Tabriz, Sannandaj, Sari, and Ahvaz) during 2006-2008. Methodology: Antibiotic susceptibility of 250 strains of Staphylococcus aureus isolated from Iranian hospitals were determined by disk diffusion method. Minimum inhibitory concentration (MICs) were determined for oxacillin and vancomycin by E-test. PCRs were used by specific primers (PCR used specific primers) for detection of mecA, vanA, vanB genes. Results: The percentage of resistance by disk diffusion method was as below: methicillin 46%, vancomycin 0%, penicillin 86%, erythromycin 42%, ciprofloxacin 29%, gentamicin 39% and clindamycin 33%. E-test MIC method showed that 43% isolates were resistant to British Microbiology Research Journal, 4(4): 454-461, 2014 455 methicillin and 4% isolates were VISA (≤ 8µg/ml). The prevalence of resistance genes in the clinical isolates were: mecA 44%, vanA 0%, vanB 0%. Conclusion: This study revealed that clinical isolates have rather high resistance to methicillin, erythromycin, gentamicin, penicillin and clindamycin We did not observe resistance to vancomycin. In order to avoid a possible outbreak involving VISA), vancomycin should be used carefully as a drug for treatment of S. aureus infections.
International Journal of Antimicrobial Agents, Feb 1, 2008
Iranian Journal of Parasitology, 2007
of urinary tract infections (UTIs) in hospitalized patients. The aim of this study was to determi... more of urinary tract infections (UTIs) in hospitalized patients. The aim of this study was to determine prevalence of UTI caused by VRE in an Iranian 1000-bed hospital and to assess the activity of commonly used antibiotics including nitrofurantoin against VRE isolates.
Social Science Medicine, Mar 31, 2008
Underlying maternal vascular disease has been implicated as one of several pathways contributing ... more Underlying maternal vascular disease has been implicated as one of several pathways contributing to preterm delivery (PTD) and psychosocial factors such as hostility, anomie, effortful coping, and mastery may be associated with PTD by affecting maternal vascular health. Using data from the Pregnancy Outcomes and Community Health (POUCH) study, we included 2,018 non-Hispanic White and 743 African American women from 52 clinics in 5 Michigan, USA communities who were interviewed at 15−27 weeks' gestation and followed to delivery. We found that relations between psychosocial factors and PTD subtypes (i.e. medically indicated, premature rupture of membranes, spontaneous labor) varied by race/ethnicity and socioeconomic position (Medicaid insurance status). Among African American women not insured by Medicaid, anomie levels in midpregnancy were positively associated with medically indicated PTD after adjusting for maternal age and education. Among all women not insured by Medicaid, hostility levels were positively associated with spontaneous PTD after adjusting for maternal race/ethnicity, age, and education. Failure to detect links between psychosocial factors and PTD risk in poorer women may be due to their excess risk in multiple PTD pathways and/or a more complex web of contributing risk factors.
The wide use of subway system by citizens underlines the importance of hygienic issues including ... more The wide use of subway system by citizens underlines the importance of hygienic issues including indoor air pollution in these public places especially in metro stations. The aim of this study was to investigate the bacterial contamination in indoor and outdoor air of two metro stations (Imam Khomeini and Sadeghiyeh stations) in Tehran subway system. In this cross sectional study, three sampling locations were selected in each station. Also, sampling was conducted in indoor air of two types (old and new) of trains. The range of bacterial colony count was 35-1501 CFU/m 3 . Maximum and minimum bacterial contamination levels in Imam Khomeini and Sadeghiyeh platform stations were averagely 1073 CFU/m 3 and 242 CFU/m 3 , respectively. 14 bacterial species and genera were isolated; among them the dominant species were Staphylococcus epidermidis, Micrococcus luteus and Bacillus spp. Results showed that bacterial concentrations in indoor air were higher than the outdoor air; also the bacterial counts correlated significantly with number of the passengers (p<0.001) and air temperature (p<0.001).
Http Dx Doi Org 10 1080 10543406 2013 789884, Jun 20, 2013
In this article, we discuss an approach for optimal sample size allocation in designing multicent... more In this article, we discuss an approach for optimal sample size allocation in designing multicenter clinical trials. The method we studied was adapted from a stratified sampling survey design. The sample size allocated to centers is a function of the center&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s treatment cost, the standard deviation of the endpoint, and the availability of patients. We illustrate our approach using two hypothetical scenarios derived from our experiences in designing and conducting multicenter clinical trials. Simulation results are also presented.
Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health o... more Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health of children. Previous studies from Jamaica reported that mean lead levels in soil are four times that of lead levels in some other parts of the world. Other studies detected lead levels in fruits and root vegetables, which were grown in areas with lead contaminated soil. In this study, we investigate environmental factors associated with blood lead concentrations in Jamaican children. The participants in this study comprised 125 typically developing (TD) children (ages 2-8 years) who served as controls in an age- and sex-matched case-control study that enrolled children from 2009-2012 in Jamaica. We administered a questionnaire to assess demographic and socioeconomic information as well as potential exposures to lead through food. Using General Linear Models (GLMs), we identified factors associated with blood lead concentrations in Jamaican children. The geometric mean blood lead concentration (GMBLC) in the sample of children in this study was 2.80 μg dL(-1). In univariable GLM analyses, GMBLC was higher for children whose parents did not have education beyond high school compared to those whose parents had attained this level (3.00 μg dL(-1) vs. 2.31 μg dL(-1); P = 0.05), children living near a high traffic road compared to those who did not (3.43 μg dL(-1) vs. 2.52 μg dL(-1); P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), and children who reported eating ackee compared to those who did not eat this fruit (2.89 μg dL(-1) vs. 1.65 μg dL(-1); P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). In multivariable analysis, living near a high traffic road was identified as an independent risk factor for higher adjusted GMBLC (3.05 μg dL(-1) vs. 2.19 μg dL(-1); P = 0.01). While our findings indicate that GMBLC in Jamaican children has dropped by at least 62% during the past two decades, children living in Jamaica still have GMBLC that is twice that of children in more developed countries. In addition, we have identified significant risk factors for higher blood lead concentrations in Jamaican children. We believe increasing awareness among parents regarding these risk factors could potentially lead to a lower level of lead exposure in Jamaican children.
This article presents the results of a systematic literature review to locate peer-reviewed journ... more This article presents the results of a systematic literature review to locate peer-reviewed journal articles that offer equivalent or absorbed radiation dose measurements for locations in outer space.
Bulletin of the World Health Organization, 2002
To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to i... more To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity we...
Social Science & Medicine, 2004
To explore traditional beliefs and practices, to assess puerperal morbidity, and to understand ca... more To explore traditional beliefs and practices, to assess puerperal morbidity, and to understand care-seeking behaviors, a qualitative and quantitative study was conducted in low socio-economic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth interviews were conducted in July and August 2000. 525 Muslim women, who were 6-8 weeks post-partum, were then interviewed at home. Maternal care was relatively good-more than three-quarters of recent mothers sought antenatal care and more than half (267/525) delivered in a hospital or maternity home. Counseling to attend post-partum clinics among facility deliveries was 16% (43/267), of which only 26% (11/43) attended. Practices during the delivery and puerperium, such as massaging the vaginal walls with mustard oil during labor to facilitate delivery and inserting vaginal or rectal herbal pessaries to facilitate 'shrinkage of the uterus' and/or 'strengthening of the backbone', were pervasive.
Social Science & Medicine, 2005
To explore traditional neonatal beliefs and care practices and to assess the predictors for givin... more To explore traditional neonatal beliefs and care practices and to assess the predictors for giving prelacteal feeds, a qualitative and quantitative study was conducted in low socioeconomic settlements of Karachi, Pakistan. Five focus group discussions and 15 in-depth semi-structured interviews were conducted in July and August 2000; structured questionnaires were administered to 525 recently delivered women through November.
Maternal and Child Health Journal, 2006
To examine the prevalence of depressive symptoms in mid-pregnancy and their relation to life circ... more To examine the prevalence of depressive symptoms in mid-pregnancy and their relation to life circumstances across the life course in a community-based sample. The Pregnancy Outcomes and Community Health (POUCH) Study enrolled women at 16-26 weeks&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; gestation from 52 clinics in five Michigan communities. At enrollment women completed a screening instrument for depressive symptoms (CES-D) and questions about life circumstances covering three &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;periods,&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; i.e. previous 6 months, adulthood, and childhood. Questions were grouped into sub-constructs (e.g., abuse, economic, substance use, loss, and legal) for each &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;period&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; and evaluated in relation to CES-D scores. Analyses included 1321 POUCH participants divided into three subgroups: teens; women &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =20 years insured by Medicaid (disadvantaged); and women &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =20 years not insured by Medicaid (advantaged). A positive CES-D screen (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =16) was more common in teens (46%) and disadvantaged women (47%) than in advantaged women (23%). Recent problems (previous 6 months) with abuse, economics, and substance use in someone close were each associated with higher adjusted mean CES-D scores (2.3-7.5 increase) in the three subgroups of women. In life course analyses, abuse and substance use in teens, and abuse and economic problems in disadvantaged and advantaged women were strongly linked to higher adjusted mean CES-D scores when these problems occurred both in childhood and adulthood (range 2.2-7.1 increase), whereas the associations were more modest when problems were confined to childhood. Strategies for addressing the public health problem of depressive symptoms in mid-pregnancy will benefit from a life course perspective.
Journal of the American Geriatrics Society, 2000