Total readmissions after CABG in Israel were difficult to predict, even with an extensive pre-discharge follow-up data. We propose that reasons for readmission vary from true emergencies to nonspecific causes, with the latter related to a lack of support services in the community. We suggest that cause-specific rehospitalizations could be a better outcome for evaluating quality of care.

The study identifies patients who would most benefit from posthospitalization community support after bypass operations. Under circumstances of limited resources, these disadvantaged groups should be targeted as a priority. Encouraging participation in existing rehabilitation programs or introducing telephone hotlines could improve health-related quality of life after coronary bypass grafting without large investments.

In outcome studies, quality of care in various institutions is typically assessed by comparing observed to expected outcome rates, after adjusting for patients' case-mix factors in logistic regression models. However, differences in patterns of outcome rates over time, especially when there is a distinction between the determinants affecting early and later events, are rarely studied. We use six-month mortality after coronary artery bypass graft operation (CABG) as an example. We present a statistically valid approach to estimate expected survival curves for different subgroups, based on a Cox survival model with time-varying effects. Bootstrap confidence intervals around the expected survival curves are constructed. This approach is applied for examining the pattern of deviation of high-mortality hospitals after CABG. Implications for quality assessment in comparative outcome studies are discussed.

In spite of substantial advances in the treatment of major depression by pharmacotherapy and other means, a significant number of depressed patients require hospitalization. In the context of the Jerusalem Collaborative Depression Project, possible precipitants of psychiatric hospitalization were sought in a cohort of patients (n = 107) who were admitted to hospitals in the Jerusalem area during a 14-month period because of a depressive episode. The patients fulfilled DSM III-R criteria for major depression, single or recurrent; bipolar 1 disorder, depressed or mixed; bipolar 2, depressed. The cohort encompassed more than two thirds of potential subjects admitted during this period with the ICD-9 equivalents of the specified diagnoses (as reported to the Israel Ministry of Health National Psychiatric Case Register) and were similar to the entire potential population in terms of their diagnostic breakdown. The patients underwent extensive socio-demographic and clinical evaluation that included detailed documentation of treatment received prior to hospitalization. Notwithstanding the absence of a comparison group of depressed patients who were not hospitalized, a number of potential precipitants were identified. These included older age (55.2% > 60 years, 20.6% > 70 years), immigration to Israel during the preceding 5 years (34.7%), concomitant physical illness (60%) which was associated with moderate to severe disability in 41% and poor quality of antidepressant pharmacotherapy prior to hospitalisation (only 24.3% received an adequate trial of antidepressant medication). Further evaluation of these and other potential factors could facilitate targeting of patient groups at particular risk for hospitalization and reduce the need for it.

The sequential analysis was an efficient method for updating patients' risk over time, where the number of events was small, relative to the number of risk factors. The addition of peri-operative factors increased significantly the predictive power of the model, adding clinical insights to the role of the hospital experience on 30 days mortality.