Evaluation of prognostic factors effect on survival time in patients with colorectal cancer, based on weibull competing-risks model

Aim: The aim of this study was to assess the association between survival of patients with colorectal cancer and prognostic factors in a competing risk parametric model using Weibull distribution

Background: The prognosis of colorectal cancer is relatively good in terms of survival time. In many prognostic studies, patients may be exposed to several types of competing events. These different causes of death are called competing risks

Methods: Data was recorded from 372 patients with colorectal cancer who registered in the Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences [Tehran, Iran] from 2004 to 2015 in a retrospective study. Analysis was performed using competing risks model and Weibull distribution. Software used for data analysis was R, and significance level was regarded as 0.05

Results: The result indicated that, at the end of follow-up, 111 [29.8%] deaths were from colorectal cancer and 14 [3.8%] deaths were due to other diseases. The average body mass index [BMI] was 24.61[SD 3.98]. The mean survival time for a patient in 372 was 62.05[SD 48.78] month with median equals to 48 months. According to competing-risks method, only stageIII [HR, 1.69; 95% CI, 1.246-2.315], stageIV[HR, 4.51; 95% CI,2.91-6.99 ] and BMI[HR, 0.96; 95% CI, 0.96-0.975] have a significant efect on patient's survival time

Conclusion: This study indicated pathologic stage[III,IV] and BMI as the prognosis, using a Weibull model with competing risks analysis, while other models without the competing events lead to significant predictors which may be due to over-estimation

Burden of gastrointestinal cancers and problem of the incomplete information; how to make up the data?

Cancer registration is an important source for measuring the burden of cancer in a population. In practice, however, quite frequently incorrect patients are registered or data items can be inaccurately recorded or not recorded at all. Also the process or quality of these registrations varies among countries. In this paper, we briefly discussed some statistical techniques including; Mortality and Incidence Analysis Model [MIAMOD], Prevalence and Incidence Analysis Model [PIAMOD], Bayesian Inference and Capture-recapture methods, which provide tools to re-correct the incomplete or misclassified cancer statistics with regards to gastrointestinal cancers

Effects of dorsal static splint on spasticity and range of motion of upper extremity of children with cerebral palsy in three time periods

Cerebral Palsy [CP] is a neurodevelopmental disorder caused by non-progressive lesions in single or multiple locations in the immature brain. Lesions of motor cortex and pyramidal tracts can lead to spasticity. Inhibition of spasticity is necessary to increase extremity mobilization, prevent postural abnormalities and provide independence in daily living activities. The purpose of this study was to determine the effects of volar static splint spasticity and range of motion of upper extremity in children with Cerebral palsy in three periods of time. The design of this study was experimental and repeated measurements. Ten children with Cerebral palsy aging 4-6 years old were non-randomly selected among children referred to occupational therapy Clinic of rehabilitation Faculty of Tehran University of Medical Sciences. Children used dorsal static splint for three months [2 hours at day and 4 hours at night]. In this study, Modified Ashworth Scale was used to evaluate spasticity and a Goniometre was used to measure passive range of motion. The results of this study showed significant reduction in the upper limb spasticity after 2 months [p