Impact of alternative approaches to assess outlying and influential observations on health care costs

The distributions of medical costs are often skewed to the right because small numbers of patients use large amounts of health care resources. Using data from a study of colon cancer costs, we show, by example, the impact and magnitude of outliers and influential observations on health care costs and compared the effects of statistical costing methods for addressing the disproportionate influence of outliers and influential observations. We used data from a retrospective cohort study of 3,842 elderly veterans with colon cancer who were enrolled in and used health care from, both the Department of Veterans Affairs and Medicare in 1999–2004. After calculating the average colon cancer episode cost and distribution for the full cohort, we used box-plot methods, Winsorization, DFBETAs, and Cook's distance to identify and assess or adjust the outlying and/or influential observations. The number of observations identified as outlying and/or influential ranged from 13 when the predicted DFBETA measurement was greater than 0.15 and the observation was a qualified box-plot outlier to 384 cases using the Winsorization method at the 5th and 95th percentiles. Average costs of colon cancer episodes using these methods were similar. The method of choice from the results of this particular analysis can be conditionally based on whether the purpose is to control only for influential observations or to simultaneously control for outliers and influential observations. Understanding how estimates could change with each approach is important in assessing the impact of a particular method on the results

Patterns of Alcohol Abuse, Depression, and Intimate Partner Violence Among Township Mothers in South Africa Over 5 Years.

Alcohol is a major contributor to the global burden of disease. In South Africa, alcohol abuse is hypothesized to correlate with women's HIV status, mental health, and partner relationships over time. All pregnant women in 12 urban, low-income, Cape Town neighborhoods were interviewed at baseline, post-birth, and at 6, 12, 36, and 60 months following delivery with retention rates from 82.5 to 94%. Women were assessed for any alcohol use, problematic drinking, depression, intimate partner violence, and HIV status. Prior to pregnancy discovery and 5 years after giving birth, alcohol use was 25.8 and 24.7%, respectively. Most women decreased their alcohol use during pregnancy. Twenty-one percent reported alcohol use on two or more assessments, and only 15% of the mothers drinking alcohol at 5 years were also drinking at baseline. Mothers with depression had a higher likelihood of drinking alcohol compared to mothers who were not depressed only at baseline and 6 months post-birth. Mothers who experienced IPV had more than twice the likelihood of drinking alcohol compared to non-IPV mothers at all assessments. HIV positive mothers were more likely to drink alcohol compared to mothers without HIV prior to pregnancy discovery and at 5 years post-birth. These longitudinal trends in alcohol use among young women in South Africa represent a large economic, social, and health burden and must be addressed in a comprehensive manner

Patterns of Alcohol Abuse, Depression, and Intimate Partner Violence Among Township Mothers in South Africa Over 5 Years.

Alcohol is a major contributor to the global burden of disease. In South Africa, alcohol abuse is hypothesized to correlate with women's HIV status, mental health, and partner relationships over time. All pregnant women in 12 urban, low-income, Cape Town neighborhoods were interviewed at baseline, post-birth, and at 6, 12, 36, and 60 months following delivery with retention rates from 82.5 to 94%. Women were assessed for any alcohol use, problematic drinking, depression, intimate partner violence, and HIV status. Prior to pregnancy discovery and 5 years after giving birth, alcohol use was 25.8 and 24.7%, respectively. Most women decreased their alcohol use during pregnancy. Twenty-one percent reported alcohol use on two or more assessments, and only 15% of the mothers drinking alcohol at 5 years were also drinking at baseline. Mothers with depression had a higher likelihood of drinking alcohol compared to mothers who were not depressed only at baseline and 6 months post-birth. Mothers who experienced IPV had more than twice the likelihood of drinking alcohol compared to non-IPV mothers at all assessments. HIV positive mothers were more likely to drink alcohol compared to mothers without HIV prior to pregnancy discovery and at 5 years post-birth. These longitudinal trends in alcohol use among young women in South Africa represent a large economic, social, and health burden and must be addressed in a comprehensive manner

Alcohol, But Not Depression or IPV, Reduces HIV Adherence Among South African Mothers Living with HIV Over 5 Years.

Alcohol, depression, and intimate partner violence (IPV) are endemic in sub-Saharan Africa. This article examines whether and how these conditions affect mothers living with HIV (MLH), compared to mothers without HIV (MWOH). In particular, we assess the influence of these comorbidities on engagement in HIV care and adherence to antiretroviral therapies (ARV) among MLH. Data on maternal HIV care are typically based on clinic samples, with substantial loss to follow-up. This study fills that gap by including all mothers in specified areas. A cohort study examines MLH in Cape Town, South Africa recruited in pregnancy and followed repeatedly for 5 years, compared to MWOH. Almost all (98%) pregnant women in 12 neighborhoods (N = 594) were recruited in pregnancy. Mothers and children were reassessed five times over 5 years with high retention rates at each of the six assessments, from 98.7% at 2 weeks to 82.8% at 5 years post-birth. MLH's uptake and adherence to HIV care was evaluated over time associated with maternal comorbidities of alcohol use, depressed mood, and IPV using mixed effects logistic regression. MLH have fewer resources (income, food, education) and are more likely to face challenges from alcohol, depression, and having seropositive partners over time than MWOH. Only 22.6% of MLH were consistently engaged in HIV care from 6 months to 5 years post-birth. At 5 years, 86.7% self-reported engaged in HIV care, 76.9% were receiving ARVs and 87% of those on ARV reported consistent ARV adherence. However, data on viral suppression are unavailable. Alcohol use, but not depressed mood or IPV, was significantly related to reduced uptake of HIV care and adherence to ARV over time. Adherence to lifelong ARV by MLH requires a combination of structural and behaviorally-focused interventions. Alcohol abuse is not typically addressed in low and middle-income countries, but is critical to support MLH

Maternal patterns of antenatal and postnatal depressed mood and the impact on child health at 3-years postpartum.

ObjectiveThe consequences of maternal depressed mood on children's growth, health, and cognitive and language development are examined over the first 3 years of life.MethodPregnant women in 24 periurban township neighborhoods in Cape Town, South Africa (N = 1,238 mothers) were randomized by neighborhood to a home visiting intervention or a standard care condition. Reassessments were conducted for 93%-85% of mothers at 2-weeks, 6-, 18-, and 36-months postbirth. Regressions were conducted on measures of children's growth, behavior, language, and cognition to examine the impact of four patterns of depressed mood: antenatal only (n = 154, 13.8%), postnatal only (n = 272, 24.3%), antenatal and postnatal (n = 220, 19.7%), and no depressed mood on any assessment (n = 473, 42.3%).ResultsPatterns of depressed mood were similar across intervention conditions. Depressed mothers were significantly less educated, had lower incomes, were less likely to be employed or to have electricity; were more likely to report problematic drinking of alcohol, experience food insecurity, interpersonal partner violence, and to be HIV seropositive. At 36 months, the pattern of maternal depressed mood over time was significantly associated with children's compromised physical growth, both in weight and height, and more internalizing and externalizing symptoms of behavior problems. Measures of language and cognition were similar across maternal patterns of depressed mood.ConclusionsMothers who report depressed mood face significantly more life challenges, both environmental stressors related to poverty and other problematic behaviors. More proximal, postnatal depressed mood appears to have a larger influence on their children, compared with antenatal depressed mood. (PsycINFO Database Recor

Alcohol, But Not Depression or IPV, Reduces HIV Adherence Among South African Mothers Living with HIV Over 5 Years.

Alcohol, depression, and intimate partner violence (IPV) are endemic in sub-Saharan Africa. This article examines whether and how these conditions affect mothers living with HIV (MLH), compared to mothers without HIV (MWOH). In particular, we assess the influence of these comorbidities on engagement in HIV care and adherence to antiretroviral therapies (ARV) among MLH. Data on maternal HIV care are typically based on clinic samples, with substantial loss to follow-up. This study fills that gap by including all mothers in specified areas. A cohort study examines MLH in Cape Town, South Africa recruited in pregnancy and followed repeatedly for 5 years, compared to MWOH. Almost all (98%) pregnant women in 12 neighborhoods (N = 594) were recruited in pregnancy. Mothers and children were reassessed five times over 5 years with high retention rates at each of the six assessments, from 98.7% at 2 weeks to 82.8% at 5 years post-birth. MLH's uptake and adherence to HIV care was evaluated over time associated with maternal comorbidities of alcohol use, depressed mood, and IPV using mixed effects logistic regression. MLH have fewer resources (income, food, education) and are more likely to face challenges from alcohol, depression, and having seropositive partners over time than MWOH. Only 22.6% of MLH were consistently engaged in HIV care from 6 months to 5 years post-birth. At 5 years, 86.7% self-reported engaged in HIV care, 76.9% were receiving ARVs and 87% of those on ARV reported consistent ARV adherence. However, data on viral suppression are unavailable. Alcohol use, but not depressed mood or IPV, was significantly related to reduced uptake of HIV care and adherence to ARV over time. Adherence to lifelong ARV by MLH requires a combination of structural and behaviorally-focused interventions. Alcohol abuse is not typically addressed in low and middle-income countries, but is critical to support MLH