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Aims: Relapse rates among cigarette smokers are high. Few studies have examined time-to-relapse using survival analysis in racially/ethnically diverse smokers and initial abstinence criteria have been inconsistent or unspecified. This study compared survival curves using two common definitions of initial abstinence. We hypothesized greater relapse rates among participants abstinent for only 24 hours (h) at the end-of-therapy (EOT) compared with 7 days. Methods: Adult smokers (59% Black, 22% Hispanic and 17% White) received 8-sessions of group cognitive behavioural therapy (CBT) plus transdermal nicotine patches and were assessed monthly up to 12 months post-EOT. Participants reporting abstinence (7-day point prevalence abstinence [ppa] or 24-h ppa) at the EOT were included in Kaplan–Meier curves. Results: Of 301 participants, 120 (40%) reported 7-day ppa at the EOT and an additional 29 (10%) reported 24-h ppa only. Over the 12-month follow-up period, nearly 50% remained abstinent. Of those who resumed smoking, most relapses occurred within the first three months. Survival curves indicated that median survival was 207 and 225 days for 7-day and 24-h definitions of abstinence, respectively. The difference in time-to-relapse between participants abstinent for 24?h at the EOT versus 7-days was not significant (p?=?0.14). Conclusions: Operationalization of initial abstinence is important for relapse analyses and comparisons of survival curves across samples. Participants reported high rates of abstinence and relapse rates were relatively low. Contrary to expectations, 24-h ppa at the EOT was not associated with greater relapse than 7-day abstinence. This suggests either measure may be utilized in relapse prevention research in racially/ethnically diverse treatment-seekers.  相似文献   
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To reduce racial and ethnic disparities in health care, managers, policy makers, and researchers need valid and reliable data on the race and ethnicity of individuals and populations. The federal government is one of the most important sources of such data. In this paper we review the strengths and weaknesses of federal data that pertain to racial and ethnic disparities in health care. We describe recent developments that are likely to influence how these data can be used in the future and discuss how local programs could make use of these data.  相似文献   
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Distributional Issues in the Analysis of Preventable Hospitalizations   总被引:1,自引:0,他引:1  
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PURPOSE: This study was designed to obtain an updated population-based perspective on anal canal cancer incidence rates, demographics, and outcomes using a nationwide database. Eight-five percent of all carcinomas of the anus are anal canal cancers, and previous studies suggest that incidence rates may be rising. Although the most successful treatment for anal canal cancer has been chemoradiation, little information at the population-level exists regarding demographics, treatment, and survival. METHODS: All patients diagnosed with anal canal cancer from 1973 to 1998 in the Surveillance Epidemiology and End Results cancer registry were analyzed. Data regarding demographics, cancer characteristics, treatment, and survival were assessed. Univariate and multivariate survival analyses were performed. RESULTS: A total of 4,841 patients were studied (mean age was 61 years; 62 percent female). Female patients were significantly older than male patients (65 vs. 58 years; P < 0.0001). There was a yearly increase in incidence of anal canal cancers (from 1973–1998). Disease prevalence by stage was localized (53 percent), regional (38 percent), and distant (9 percent). Racial/stage differences were seen, because black patients had less localized disease than white patients (46 vs. 53 percent; P < 0.01). Overall five-year survival for the entire cohort was 53 percent, and cancer-specific survival was 84 percent. Survival improved per decade (based on year of diagnosis). Significant survival differences in race were noted, but were less when the receipt of treatment was considered. CONCLUSION: Although most anal canal cancer reviews are single institutional series, this study was performed with population-based data. The incidence of anal canal cancer is increasing, and overall survival rates are improving. Important disparities in care were identified, which need to be addressed.  相似文献   
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