An autoregressive integrated moving average model for short-term prediction of hepatitis C virus seropositivity among male volunteer blood donors in Karachi, Pakistan

Aim: To identify the stochastic autoregressive integrated moving average (ARIMA) model for short term forecasting of hepatitis C virus (HCV) seropositivity among volunteer blood donors in Karachi, Pakistan. Methods: Ninety-six months (1998-2005) data on HCV seropositive cases (1000(-1) x month(-1)) among male volunteer blood donors tested at four major blood banks in Karachi, Pakistan were subjected to ARIMA modeling. Subsequently, a fitted ARIMA model was used to forecast HCV seropositive donors for 91-96 mo to contrast with observed series of the same months. To assess the forecast accuracy, the mean absolute error rate (%) between the observed and predicted HCV seroprevalence was calculated. Finally, a fitted ARIMA model was used for short-term forecasts beyond the observed series. Results: The goodness-of-fit test of the optimum ARIMA (2,1,7) model showed non-significant autocorrelations in the residuals of the model. The forecasts by ARIMA for 91-96 mo closely followed the pattern of observed series for the same months, with mean monthly absolute forecast errors (%) over 6 mo of 6.5%. The short-term forecasts beyond the observed series adequately captured the pattern in the data and showed increasing tendency of HCV seropositivity with a mean +/- SD HCV seroprevalence (1000(-1) x month(-1)) of 24.3 +/- 1.4 over the forecast interval. Conclusion: To curtail HCV spread, public health authorities need to educate communities and health care providers about HCV transmission routes based on known HCV epidemiology in Pakistan and its neighboring countries. Future research may focus on factors associated with hyperendemic levels of HCV infection

Cohort analysis of directly observed treatment outcomes for tuberculosis patients in urban Pakistan

Background: This quasi-experimental cohort study aimed to evaluate World Health Organization (WHO) defined tuberculosis (TB) treatment outcomes for Patients under directly observed treatment at a health facility (clinic DOT) or at home (family DOT) in urban Pakistan. Methods: We enrolled 582 sputum smear-positive TB Patients being treated by either clinic DOT (n = 295) or family DOT (n = 287) in 11 treatment centres. Patients and/or family members were interviewed for baseline measurements. WHO-defined treatment outcomes were evaluated at the end of treatment. Proportions of \u27cured\u27 Patients were computed. A log-binomial model was used to evaluate the associations of various factors with \u27cured\u27 status. Results: The proportion of \u27cured\u27 Patients was respectively 66% and 34% in the clinic DOT and family DOT groups (risk difference 0.32, 95%CI 0.24-0.39). Patients on clinic DOT were more likely to achieve cure (adjusted relative risk [RR(adj)] 1.85, 95%CI 1.43-2.39) than those on family DOT, as were Patients satisfied with their health care worker\u27s attitude (RR(adj) 5.73, 95%CI 2.54-12.96). Conclusion: Clinic DOT nearly doubled the proportion of cured Patients compared to family DOT. Efforts to improve care-provider attitudes to enhance Patient satisfaction, and effective implementation of the WHO\u27s public-private mix approach, may enhance TB control in this and similar settings

Peer pressure and family smoking habits influence smoking uptake in teenage boys attending school: multilevel modeling of survey data.

Introduction: Among young teens, about one in five smokes worldwide. Adolescents spend a considerable amount of their time in school, and the school environment is therefore important for child health practices and outcomes. Objectives: We aimed to investigate the impact on smoking behavior of the school environment and the personal characteristics of male teenage students attending schools in Pakistan, taking into account the survey sampling structure. Methods: A two-stage cluster sampling with stratification was employed, and we interviewed 772 male secondary school students. We adopted random effect and generalizing estimating equation models. Results: Peer pressure in particular had a strong influence on adolescents smoking; those whose friends smoked were up to 6 times more likely to smoke. Family smoking was also significantly associated with adolescents smoking, but those students whose mother was educated were 50% less likely to smoke. The fitted random effect model indicated that the between school variability was significant (p-value \u3c 0.01), indicating differences in smoking habits between schools. A random coefficient model showed that variability among schools was not significantly different for public and private schools. Conclusion: Public health campaigns for smoking cessation should target not only the individual but also the families of adolescents attending schools

Multilevel modeling of binary outcomes with three-level complex health survey data.

Complex survey designs often involve unequal selection probabilities of clus-ters or units within clusters. When estimating models for complex survey data, scaled weights are incorporated into the likelihood, producing a pseudo likeli-hood. In a 3-level weighted analysis for a binary outcome, we implemented two methods for scaling the sampling weights in the National Health Survey of Pa-kistan (NHSP). For NHSP with health care utilization as a binary outcome we found age, gender, household (HH) goods, urban/rural status, community de-velopment index, province and marital status as significant predictors of health care utilization (p-value \u3c 0.05). The variance of the random intercepts using scaling method 1 is estimated as 0.0961 (standard error 0.0339) for PSU level, and 0.2726 (standard error 0.0995) for household level respectively. Both esti-mates are significantly different from zero (p-value \u3c 0.05) and indicate consid-erable heterogeneity in health care utilization with respect to households and PSUs. The results of the NHSP data analysis showed that all three analyses, weighted (two scaling methods) and un-weighted, converged to almost identical results with few exceptions. This may have occurred because of the large num-ber of 3rd and 2nd level clusters and relatively small ICC. We performed a sim-ulation study to assess the effect of varying prevalence and intra-class correla-tion coefficients (ICCs) on bias of fixed effect parameters and variance components of a multilevel pseudo maximum likelihood (weighted) analysis. The simulation results showed that the performance of the scaled weighted estimators is satisfactory for both scaling methods. Incorporating simulation into the analysis of complex multilevel surveys allows the integrity of the results to be tested and is recommended as good practice

Poor knowledge--predictor of nonadherence to universal precautions for blood borne pathogens at first level care facilities in Pakistan

Background: We conducted an assessment of knowledge about blood borne pathogens (BBP) and use of universal precautions at first level care facilities (FLCF) in two districts of Pakistan.Methods: We conducted a cross-sectional survey and selected three different types of FLCFs ; public, general practitioners and unqualified practitioners through stratified random sampling technique. At each facility, we interviewed a prescriber, a dispenser, and a housekeeper for knowledge of BBPs transmission and preventive practices, risk perception, and use of universal precautions. We performed multiple linear regression to assess the effect of knowledge score (11 items) on the practice of universal precautions score (4 items- use of gloves, gown, needle recapping, and HBV vaccination).Results: We interviewed 239 subjects. Most of the participants 128 (53%) were recruited from general practitioners clinics and 166 (69.5%) of them were dispensers. Mean (SD) knowledge score was 3.8 (2.3) with median of 4. MBBS prescribers had the highest knowledge score while the housekeepers had the lowest. Mean universal precautions use score was 2.7 +/- 2.1. Knowledge about mode of transmission and the work experience alone, significantly predicted universal precaution use in multiple linear regression model (adR2 = 0.093).CONCLUSION: Knowledge about mode of transmission of blood borne pathogens is very low. Use of universal precautions can improve with increase in knowledge

Association of tobacco use and other determinants with pregnancy outcomes: a multicentre hospital-based case-control study in Karachi, Pakistan.

OBJECTIVES: The study aimed to identify the effects of maternal tobacco consumption during pregnancy and other factors on birth outcomes and obstetric complications in Karachi, Pakistan. DESIGN: A multicentre hospital-based case-control study. SETTING: Four leading maternity hospitals of Karachi. PARTICIPANTS: A random sample of 1275 women coming to the gynaecology and obstetric department of selected hospitals for delivery was interviewed within 48 hours of delivery from wards. Cases were women with adverse birth outcomes and obstetric complications, while controls were women who had normal uncomplicated delivery. PRIMARY AND SECONDARY OUTCOME MEASURES: Adverse birth outcomes (preterm delivery, low birth weight, stillbirth, low Apgar score) and obstetric complications (antepartum haemorrhage, caesarean section, etc). RESULTS: Final multiple logistic regression analysis revealed that with every 1 year increase in age the odds of being a case was 1.03 times as compared with being a control. Tobacco use (adjusted OR (aOR): 2.24; 95% CI 1.56 to 3.23), having no slits in the kitchen (proxy indicator for indoor air pollution) (aOR=1.90; 95% CI 1.05 to 3.43), gravidity (aOR=0.83; 95% CI 0.73 to 0.93), non-booked hospital cases (aOR=1.87; 95% CI 1.38 to 2.74), history of stillbirth (aOR=4.06; 95% CI 2.36 to 6.97), miscarriages (aOR=1.91; 95% CI 1.27 to 2.85) and preterm delivery (aOR=6.04; 95% CI 2.52 to 14.48) were significantly associated with being a case as compared with control. CONCLUSIONS: This study suggests that women who had adverse pregnancy outcomes were more likely to have exposure to tobacco, previous history of adverse birth outcomes and were non-booked cases. Engagement of stakeholders in tobacco control for providing health education, incorporating tobacco use in women in the tobacco control policy and designing interventions for tobacco use cessation is warranted. Prenatal care and health education might help in preventing such adverse events

Association between asthma and dental caries amongst 12 - 15 years old children: A school-based cross-sectional study in karachi, pakistan

Objective: The study aimed to determine an association between dental caries and asthma among 12 to 15 years old children. Methods: This is a school-based cross-sectional study conducted from January to February 2016. A random sample of 544 children aged 12 - 15 years were enrolled from five private schools of Karachi. Dental caries was assessed using DMFT Index (Decayed, Missing, Filled teeth). The main exposure variable was asthma and information on it was collected through the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire.Results: The data was analyzed using Cox Proportional Hazard algorithm. Crude and adjusted prevalence ratios with 95% CI were reported. Total 554 children, 306 (56.3%) boys and 43.7% girls participated in the study. Mean age of children was 13.2 ± 0.05 years. Total number of children with DMFT \u3e 0 was 30.5%. The decayed component contributed largely (22.8%) to the DMFT score. Overall prevalence of asthma was 20%. Prevalence of caries in asthmatic children was 28.4% as compared to 31% among non-asthmatic children. Adjusted prevalence ratio of dental caries in asthmatic children was 0.8 (95% CI 0.6 - 1.3) after adjusting for carious food intake, age, oral hygiene index and dentist visit; the association between asthma and dental caries turned out to be in-significant.Conclusions: There was no association observed between asthma and dental caries among the children examined in this study

Quality of life of road traffic injury survivors aged 15-44 years suffered from moderate and severe head injuries in Karachi, Pakistan

Background: Most of Road traffic injuries are predicted to be the third leading contributor to the global burden of disease by 2020 and patients end up into head injuries which leave devastating impacts on individual and society. Quality of Life After Brain Injury (QOLIBRI) is a specific tool that measures quality of life in head injury patients.Methods: This was a cross sectional study among 300 patients aged 15-45 years, attended emergency department of the Aga khan University Hospital. Structured questionnaire included demography, injury details, QOLIBRI, GOSE and WHO Disability Assessment Scale (WHODAS 12 items). Severity of injury was determined by Glasgow coma score of subjects reported in emergency department on admission. This was one time telephonic survey in which bidirectional data was collected from subjects about injury and outcome (QOLIBRI). To identify the determinants of QOL among RTI survivors with head injury multiple linear regressions was applied.Results: The mean QOL score for study sample was 69.86 ± (15.89. Most of the patients 210 (70%) were motorbike rider followed by four-wheelers 69 (23%). Mean age of RTI participants was 28.10 ± (7.68) years. The quality of life decreases with increase in severity of head injury by -697.32 (95% CI; -1006.44, -388.20).Conclusions: This study suggests severity of head injury, recovery time, surgery resulting from RTA, employment, family system and disability to have long term impact on QOL of RTI survivors

A systematic review of observational studies, demonstrating smoking among school going adolescents

Objective: To characterize the methods of design and analysis currently adopted in survey research of school-based observational studies for smoking, and to identify the common pitfalls made by researchers.Methods: The systematic review was conducted in 2009 and consisted of observational studies in school settings published between January 2005 and January 2009. Smoking status was the main outcome of interest. Following Cochrane style, five steps were followed: setting selection criteria for studies and conducting a literature search; review of abstracts; review of complete articles; data extraction and quality assessment of included studies; and, finally, synthesis of studies.Results: Of the 292 abstracts retrieved, 45 (15.4%) articles were selected for the final review. Inconsistencies were found in the definition of smoking behaviour which impeded generalisability. Individual-level factors had importance, but environmental level factors were also important in studying the aetiology of smoking. Results showed that studies inappropriately reported sample size estimation and important confounding factors. Hierarchical linear modelling, random effects modelling and structural equation modelling were employed in comparatively few studies.Conclusions: There were concerns regarding data analysis of complex surveys. Fifty five percent of reviewed studies ignored environmental effects which may have produced unreliable inferences. Multi-level analysis assisted in understanding school-level effects