Showing papers by "Robert Rush published in 2008"
TL;DR: It was concluded that mean square statistics were relatively independent of sample size for polytomous data and that misfit to the model could be identified using published recommended ranges.
Abstract: BACKGROUND: Previous research on educational data has demonstrated that Rasch fit statistics (mean squares and t-statistics) are highly susceptible to sample size variation for dichotomously scored rating data, although little is known about this relationship for polytomous data. These statistics help inform researchers about how well items fit to a unidimensional latent trait, and are an important adjunct to modern psychometrics. Given the increasing use of Rasch models in health research the purpose of this study was therefore to explore the relationship between fit statistics and sample size for polytomous data. METHODS: Data were collated from a heterogeneous sample of cancer patients (n = 4072) who had completed both the Patient Health Questionnaire - 9 and the Hospital Anxiety and Depression Scale. Ten samples were drawn with replacement for each of eight sample sizes (n = 25 to n = 3200). The Rating and Partial Credit Models were applied and the mean square and t-fit statistics (infit/outfit) derived for each model. RESULTS: The results demonstrated that t-statistics were highly sensitive to sample size, whereas mean square statistics remained relatively stable for polytomous data. CONCLUSION: It was concluded that mean square statistics were relatively independent of sample size for polytomous data and that misfit to the model could be identified using published recommended ranges.
298 citations
TL;DR: Clinically significant emotional distress, substantial pain, and--to a lesser extent--older age, were associated with a positive response, and emotional distress played the most important role.
Abstract: Purpose Cancer is associated with an increased risk of suicide and attempted suicide. However, we do not know how many cancer patients have thoughts that they would be better off dead or thoughts of hurting themselves. This study aimed to determine the prevalence of such thoughts in cancer outpatients and which patients are most likely to have them. Patients and Methods A survey of consecutive patients who attended the outpatient clinics of a regional cancer center in Edinburgh, United Kingdom. Patients completed the Patient Health Questionnaire-9 (PHQ-9), which included Item 9 that asks patients if they have had thoughts of being better off dead or of hurting themselves in some way in the previous 2 weeks. Those who reported having had such thoughts for at least several days in this period were labeled as positive responders. Patients also completed the Hospital Anxiety and Depression Scale (HADS) and a pain scale. The participating patients’ cancer diagnoses and treatments were obtained from the cancer ...
174 citations
TL;DR: Clinicopathological features and outcome of women with endometrioid and serous ovarian adenocarcinoma were compared.
Abstract: BACKGROUND. Clinicopathological features and outcome of women with endo-metrioid and serous ovarian adenocarcinoma were compared.
METHODS. Between 1984 and 2004, baseline and follow-up data were prospectively recorded on 1545 patients with ovarian cancer. Of these, 270 had pure endometrioid tumors; 659 had pure serous adenocarcinoma of the ovary. Response to platinum-based chemotherapy (PBC) overall survival, stage-for-stage median progression-free survival (PFS), and cause-specific median survival were compared. Independent predictors of survival were examined by using multivariate analyses.
RESULTS. Median age of diagnosis for patients with endometrioid tumors was younger than those with serous adenocarcinoma of the ovary (60 years vs 62 years; P =.013). They presented more often with early disease (stage I and 11; 50% vs 17%; P <.001), had less ascites, and had better performance status both overall and for stage II and III disease. More endometrioid tumors were optimally debulked overall (71% vs 45%; P <.001), but there was no difference according to stage. Objective and CA125 PBC response rates were not significantly different, but median PFS was better for patients with endometrioid tumors (24 months vs 13 months; P <.0001) as was overall median survival (48 months vs 22 months; P <.0001). This relation remained for stage II and III disease and for moderately and poorly differentiated tumors. Patients with concurrent endometrioid ovarian and endometrial malignancies had a survival advantage compared with those with ovarian malignancies alone. Independent predictors of survival after PBC were histological type, debulking status, and disease stage.
CONCLUSIONS. Despite similar PBC response rates, endometrioid histology is associated with better survival compared with serous adenocarcinoma of the ovary, even with stage III or poorly differentiated tumors.
91 citations