***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Introduction Antiretroviral drug interventions significantly reduce the risk of HIV transmission to infants through breastfeeding . We report diarrhoea prevalence and all-cause mortality at 12 months of age according to infant feeding practice s , among infants born to HIV-infected and uninfected mothers in South Africa . Methods A non-r and omised intervention cohort study that followed both HIV-infected and HIV-uninfected mothers and their infants until 18 months of age . Mothers were supported in their infant feeding choice . Detailed morbidity and vital status data were collected over the first year . At the time , only single dose nevirapine was available to prevent mother-to-child transmission of HIV . Results Among 2,589 infants , detailed feeding data and vital status were available for 1,082 HIV-exposed infants and 1,155 HIV non-exposed infants . Among exclusively breastfed ( EBF ) infants there were 9.4 diarrhoeal days per 1,000 child days ( 95%CI . 9.12 - 9.82 ) while among infants who were never breastfed there were 15.6 diarrhoeal days per 1,000 child days ( 95%CI . 14.62 - 16.59 ) . Exclusive breastfeeding was associated with fewer acute , persistent and total diarrhoeal events than mixed or no breastfeeding in both HIV-exposed infants and also infants of HIV uninfected mothers . In an adjusted cox regression analysis , the risk of death among all infants by 12 months of age was significantly greater in those who were never breastfed ( aHR 3.5 , p<0.001 ) or mixed fed ( aHR 2.65 , p<0.001 ) compared with those who were EBF . In separate multivariable analyses , infants who were EBF for shorter duration s had an increased risk of death compared to those EBF for 5 - 6 months [ aHR 2.18 ( 95 % CI , 1.56 - 3.01 ) ; p<0.001 ] . Discussion In the context of antiretroviral drugs being scaled-up to eliminate new HIV infections among children , there is strong justification for financial and human re source investment to promote and support exclusive breastfeeding to improve HIV-free survival of HIV-exposed and non-exposed infants OBJECTIVE Our purpose was to measure the agreement , reliability , construct validity , and feasibility of a measurement tool to assess  systematic review s ( AMSTAR ) . STUDY DESIGN AND SETTING We r and omly selected 30 systematic review s from a data base . Each was assessed by two review ers using : ( 1 ) the enhanced quality assessment question naire ( Overview of Quality Assessment Question naire [ OQAQ ] ) ; ( 2 ) Sacks ' instrument ; and ( 3 ) our newly developed measurement tool ( AMSTAR ) . We report on reliability ( interobserver kappas of the 11 AMSTAR items ) , intraclass correlation coefficients ( ICCs ) of the sum scores , construct validity ( ICCs of the sum scores of AMSTAR compared with those of other instruments ) , and completion times . RESULTS The interrater agreement of the individual items of AMSTAR was substantial with a mean kappa of 0.70 ( 95 % confidence interval [ CI ] : 0.57 , 0.83 ) ( range : 0.38 - 1.0 ) . Kappas recorded for the other instruments were 0.63 ( 95 % CI : 0.38 , 0.78 ) for enhanced OQAQ and 0.40 ( 95 % CI : 0.29 , 0.50 ) for the Sacks ' instrument . The ICC of the total score for AMSTAR was 0.84 ( 95 % CI : 0.65 , 0.92 ) compared with 0.91 ( 95 % CI : 0.82 , 0.96 ) for OQAQ and 0.86 ( 95 % CI : 0.71 , 0.94 ) for the Sacks ' instrument . AMSTAR proved easy to apply , each review taking about 15 minutes to complete . CONCLUSIONS AMSTAR has good agreement , reliability , construct validity , and feasibility . These findings need confirmation by a broader range of assessors and a more diverse range of review BACKGROUND In low-re source setting s , many programs recommend that women who are infected with the human immunodeficiency virus ( HIV ) stop breast-feeding early . We conducted a r and omized trial to evaluate whether abrupt weaning at 4 months as compared with the st and ard practice has a net benefit for HIV-free survival of children . METHODS We enrolled 958 HIV-infected women and their infants in Lusaka , Zambia . All the women planned to breast-feed exclusively to 4 months ; 481 were r and omly assigned to a counseling program that encouraged abrupt weaning at 4 months , and 477 to a program that encouraged continued breast-feeding for as long as the women chose . The primary outcome was either HIV infection or death of the child by 24 months . RESULTS In the intervention group , 69.0 % of the mothers stopped breast-feeding at 5 months or earlier ; 68.8 % of these women reported the completion of weaning in less than 2 days . In the control group , the median duration of breast-feeding was 16 months . In the overall cohort , there was no significant difference between the groups in the rate of HIV-free survival among the children ; 68.4 % and 64.0 % survived to 24 months without HIV infection in the intervention and control groups , respectively ( P=0.13 ) . Among infants who were still being breast-fed and were not infected with HIV at 4 months , there was no significant difference between the groups in HIV-free survival at 24 months ( 83.9 % and 80.7 % in the intervention and control groups , respectively ; P=0.27 ) . Children who were infected with HIV by 4 months had a higher mortality by 24 months if they had been assigned to the intervention group than if they had been assigned to the control group ( 73.6 % vs. 54.8 % , P=0.007 ) . CONCLUSIONS Early , abrupt cessation of breast-feeding by HIV-infected women in a low-re source setting , such as Lusaka , Zambia , does not improve the rate of HIV-free survival among children born to HIV-infected mothers and is harmful to HIV-infected infants . ( Clinical Trials.gov number , NCT00310726 . BACKGROUND Early weaning has been recommended to reduce postnatal human immunodeficiency virus ( HIV ) transmission . We evaluated the safety of stopping breast-feeding at different ages for mortality of uninfected children born to HIV-infected mothers . METHODS During a trial of early weaning , 958 HIV-infected mothers and their infants were recruited and followed up from birth to 24 months postpartum in Lusaka , Zambia . One-half of the cohort was r and omized to wean abruptly at 4 months , and the other half of the cohort was r and omized to continue breast-feeding . We examined associations between uninfected child mortality and actual breast-feeding duration and investigated possible confounding and effect modification . RESULTS The mortality rate among 749 uninfected children was 9.4 % by 12 months of age and 13.6 % by 24 months of age . Weaning during the interval encouraged by the protocol ( 4 - 5 months of age ) was associated with a 2.03-fold increased risk of mortality ( 95 % confidence interval [ CI ] , 1.13 - 3.65 ) , weaning at 6 - 11 months of age was associated with a 3.54-fold increase ( 95 % CI , 1.68 - 7.46 ) , and weaning at 12 - 18 months of age was associated with a 4.22-fold increase ( 95 % CI , 1.59 - 11.24 ) . Significant effect modification was detected , such that risks associated with weaning were stronger among infants born to mothers with higher CD4(+ ) cell counts ( > 350 cells/microL ) . CONCLUSION Shortening the normal duration of breast-feeding for uninfected children born to HIV-infected mothers living in low-re source setting s is associated with significant increases in mortality extending into the second year of life . Intensive nutritional and counseling interventions reduce but do not eliminate this excess mortality OBJECTIVES Early infant mortality  has not declined as rapidly as child mortality in many countries . Identification of risk factors for early infant mortality may help inform the design of intervention strategies . METHODS Over the period 1994 - 97 , 15,469 live-born , singleton infants in rural Nepal were followed to 24 weeks of age to identify risk factors for mortality within 0 - 7 days , 8 - 28 days , and 4 - 24 weeks after the birth . FINDINGS In multivariate models , maternal and paternal education reduced mortality between 4 and 24 weeks only : odds ratios ( OR ) 0.28 ( 95 % confidence interval ( CI ) = 0.12 - 0.66 ) and 0.63 ( 95 % CI = 0.44 - 0.88 ) , respectively . Miscarriage in the previous pregnancy predicted mortality in the first week of life ( OR = 1.98 , 95 % CI = 1.37 - 2.87 ) , whereas prior child deaths increased the risk of post-neonatal death ( OR = 1.85 , 95 % CI 1.24 - 2.75 ) . A larger maternal mid-upper arm circumference reduced the risk of infant death during the first week of life ( OR = 0.88 , 95 % CI = 0.81 - 0.95 ) . Infants of women who did not receive any  tetanus vaccinations during pregnancy or who had severe illness during the third trimester were more likely to die in the neonatal period . Maternal mortality was strongly associated with infant mortality ( OR = 6.43 , 95 % CI = 2.35 - 17.56 at 0 - 7 days ; OR = 11.73 , 95 % CI = 3.82 - 36.00 at 8 - 28 days ; and OR = 51.68 , 95 % CI = 20.26 - 131.80 at 4 - 24 weeks ) . CONCLUSION Risk factors for early infant mortality varied with the age of the infant . Factors amenable to intervention included efforts aim ed at maternal morbidity and mortality and increased arm circumference during pregnancy Objective : To examine whether maternal HIV disease stage during pregnancy and child malnutrition are associated with child mortality . Design : Prospect i ve cohort study in Tanzania . Methods : Indicators of disease stage were assessed for 939 HIV-infected women during pregnancy and at delivery , and children 's anthropometric status was obtained at scheduled monthly clinic visits after delivery . Children were followed up for survival status until 24 months after birth . Results : Advanced maternal HIV disease during pregnancy ( CD4 count < 350 vs. ≥350 cells/mm3 ) was associated with increased risk of child mortality through 24 months of age ( hazard ratio [ HR ] = 1.74 , 95 % confidence interval [ CI ] : 1.32 to 2.30 ) . CD4 count < 350 cells/mm3 was also associated with an increased risk of death among children who remained HIV-negative during follow-up ( HR = 2.00 , 95 % CI : 1.36 to 2.94 ) . Low maternal hemoglobin concentration and child undernutrition were related to an increased risk of mortality in this cohort of children . Conclusions : Low maternal CD4 cell count during pregnancy is related to increased risk of mortality in children born to HIV-infected women . Care and treatment for HIV disease , including highly active antiretroviral therapy to pregnant women , could improve child survival . Prevention and treatment of undernutrition in children remain critical interventions in setting s with high HIV prevalence Objectives : HAART for prevention of mother-to-child HIV transmission ( MTCT ) may impact long-term survival of women and children . Design : R and omized clinical trial . Methods : HIV-infected pregnant women with CD4 + cell count at least 200 cells/&mgr;l were r and omly assigned to  abacavir , zidovudine , lamivudine  ( arm A ) or lopinavir – ritonavir , zidovudine – lamivudine ( arm B ) from week 26 to 34 gestation through planned weaning by 6 months postpartum . Women with baseline CD4 + cell count less than 200 cells/&mgr;l received nevirapine – zidovudine – lamivudine indefinitely ( Obs arm ) , as did r and omized women later qualifying for treatment . Results : Among 560 r and omized and 170 observational women enrolled , there were 14 deaths ( 1.9 % ) – one antenatally ( Obs ) , three from delivery to 6 months postpartum ( 1 arm A , 2 Obs ) , and 10 from 6 to 24 months postpartum ( 5 arm A , 3 arm B , 2 Obs ) . Time to death or CD4 
    Output:
    
The loss of a mother was associated with increased mortality among children , especially when maternal death occurred in the first year of the child 's life