Issues for stratified randomization based on a factor derived from a continuous baseline variable

2010 ◽  
Vol 10 (3) ◽  
pp. 232-235 ◽  
Author(s):  
Yongming Qu
Keyword(s):  
2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii183-ii183
Author(s):  
Kevin Fan ◽  
Nafisha Lalani ◽  
Nathalie Levasseur ◽  
Andra Krauze ◽  
Lovedeep Gondara ◽  
...  

Abstract PURPOSE We aimed to investigate whether systemic therapy (ST) use around the time of brain radiotherapy (RT) predicts overall survival for patients with brain metastases (BM). We also aimed to validate the Diagnosis-Specific Graded Prognostic Assessment (DS-GPA) in a population-based cohort. METHODS We used provincial RT and pharmacy databases to retrospectively review all adult patients in British Columbia, Canada, who received a first course of RT for BMs between 2012 and 2016. We used a randomly selected subset with complete baseline data to develop a multivariate analysis (MVA)-based nomogram including ST use to predict survival after RT and to validate the DS-GPA. RESULTS In our 3095-patient cohort, the median overall survival (OS) of the 999 recipients of ST after RT was 5.0 months (CI 4.1-6.0) longer than the OS of the 2096 non-recipients of ST after RT (p< 0.0001): targeted therapy (HR 0.42, CI 0.37-0.48), hormone therapy (HR 0.45, CI 0.36-0.55) and cytotoxic chemotherapy (HR 0.71, CI 0.64-0.79). The OS of patients who discontinued ST after RT was 0.9 months (CI 0.3-1.4) shorter than the OS of those who did not receive ST before nor after RT (p< 0.0001). A MVA in the 200-patient subset demonstrated that the traditional baseline variables: cancer diagnosis, age, performance status, presence of extracranial disease, and number of BMs predicted survival, as did the novel variables: ST use before RT and ST use after RT. The MVA-based nomogram had a bootstrap-corrected Harrell’s Concordance Index of 0.70. In the 179 patients within this subset with DS-GPA-compatible diagnoses, the DS-GPA overestimated OS by 6.3 months (CI 5.3- 9.8) (p= 0.0006). CONCLUSIONS The type and timing of ST use around RT predict survival for patients with BMs. A novel baseline variable “ST planned after RT” should be prospectively collected to validate these findings in other cohorts.


2009 ◽  
Vol 27 (21) ◽  
pp. 3465-3471 ◽  
Author(s):  
Nancy E. Kemeny ◽  
Fidel D. Huitzil Melendez ◽  
Marinela Capanu ◽  
Philip B. Paty ◽  
Yuman Fong ◽  
...  

Purpose To determine the conversion to resectability in patients with unresectable liver metastases from colorectal cancer treated with hepatic arterial infusion (HAI) plus systemic oxaliplatin and irinotecan (CPT-11). Patients and Methods Forty-nine patients with unresectable liver metastases (53% previously treated with chemotherapy) were enrolled onto a phase I protocol with HAI floxuridine and dexamethasone plus systemic chemotherapy with oxaliplatin and irinotecan. Results Ninety-two percent of the 49 patients had complete (8%) or partial (84%) response, and 23 (47%) of the 49 patients were able to undergo resection in a group of patients with extensive disease (73% with > five liver lesions, 98% with bilobar disease, 86% with ≥ six segments involved). For chemotherapy-naïve and previously treated patients, the median survival from the start of HAI therapy was 50.8 and 35 months, respectively. The only baseline variable significantly associated with a higher resection rate was female sex. Variables reflecting extensive anatomic disease, such as number of lesions or number of vessels involved, were not significantly associated with the probability of resection. Conclusion The combination of regional HAI floxuridine/dexamethasone and systemic oxaliplatin and irinotecan is an effective regimen for the treatment of patients with unresectable liver metastases from colorectal cancer, demonstrating a 47% conversion to resection (57% in chemotherapy-naïve patients). Future randomized trials should compare HAI plus systemic chemotherapy with systemic therapy alone to assess the additional value of HAI therapy in converting patients with hepatic metastases to resectability.


Lung ◽  
2022 ◽  
Author(s):  
Hyun J. Kim ◽  
Laurie D. Snyder ◽  
Megan L. Neely ◽  
Anne S. Hellkamp ◽  
David L. Hotchkin ◽  
...  

Abstract Purpose To assess the impact of concomitant emphysema on outcomes in patients with idiopathic pulmonary fibrosis (IPF). Methods The IPF-PRO Registry is a US registry of patients with IPF. The presence of combined pulmonary fibrosis and emphysema (CPFE) at enrollment was determined by investigators’ review of an HRCT scan. Associations between emphysema and clinical outcomes were analyzed using Cox proportional hazards models. Results Of 934 patients, 119 (12.7%) had CPFE. Compared with patients with IPF alone, patients with CPFE were older (median 72 vs 70 years); higher proportions were current/former smokers (88.2% vs 63.7%), used oxygen with activity (49.6% vs 31.9%) or at rest (30.8% vs 18.4%), had congestive heart failure (13.6% vs 4.8%) and had prior respiratory hospitalization (25.0% vs 16.7%); they had higher FVC (median 71.8 vs 69.4% predicted) and lower DLco (median 35.3 vs 43.6% predicted). In patients with CPFE and IPF alone, respectively, at 1 year, rates of death or lung transplant were 17.5% (95% CI: 11.7, 25.8) and 11.2% (9.2, 13.6) and rates of hospitalization were 21.6% (14.6, 29.6) and 20.6% (17.9, 23.5). There were no significant associations between emphysema and any outcome after adjustment for baseline variables. No baseline variable predicted outcomes better in IPF alone than in CPFE. Conclusion Approximately 13% of patients in the IPF-PRO Registry had CPFE. Physiologic characteristics and comorbidities of patients with CPFE differed from those of patients with IPF alone, but the presence of emphysema did not drive outcomes after adjustment for baseline covariates. Trial registration ClinicalTrials.gov, NCT01915511; registered August 5, 2013.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 7509-7509 ◽  
Author(s):  
M. S. Kaminski ◽  
D. Hamstra ◽  
J. Estes ◽  
R. Wahl

7509 Background: The FLIPI is potentially useful in predicting clinical outcome and comparing treatment results among clinical studies in FL. We recently reported the results of I-131 tositumomab as frontline treatment in 76 pts with advanced-stage FL (NEJM 325:441, 2005). A single 1-week course resulted in a 95% and a 75% overall and complete response (CR) rate, respectively, and at a median follow-up of 5.1 years median progression-free survival (PFS) was 6.1 yrs. In multivariate analyses, bone marrow involvement was the only baseline variable that had a significant effect on PFS. Methods: To evaluate whether baseline FLIPI scores in this study could predict outcome and to compare this pt population with that in other frontline studies, the records of all 76 patients were reviewed. Results: FLIPI scores were available for 74 of the 76 pts: 11 pts (15%) low risk, 37 (50%) intermediate risk, and 26 (35%) high risk. CR rates for each risk group were 82%, 73%, and 73%, respectively. 5-yr PFS were 63% (35–92%, 95% CI), 63% (47–78%), and 52% (33–71%), respectively, p = 0.322. Grouping low + intermediate risk vs. high for PFS: p = 0.134. 5-yr overall survival (OS) rates were 100%, 95% (87–100%), 78% (62– 93%), respectively, p = 0.072, but grouping low + intermediate risk vs. high p = 0.028. A comparison to other frontline studies is below. Conclusions: The FLIPI did not predict for PFS or OS in FL pts treated with single-agent I-131 Tositumomab. However, an OS difference was seen when low + intermediate risk pts were grouped and compared with high risk pts. The distribution of FLIPI scores amongst pts in this study is similar to that observed in other front-line FL studies. Further studies exploring single-agent radioimmunotherapy vs. chemo/radioimmunotherapy combinations are warranted. [Table: see text] [Table: see text]


Author(s):  
Deborah A Ellis ◽  
Jillian Rhind ◽  
April Idalski Carcone ◽  
Meredyth Evans ◽  
Jill Weissberg-Benchell ◽  
...  

Abstract Objectives Adolescents of color are underrepresented in behavioral health research. Study aims were to quantify the amount and types of outreach effort needed to recruit young Black adolescents with type 1 diabetes and their primary caregiver into a clinical trial evaluating a parenting intervention and to determine if degree of recruitment difficulty was related to demographic, diabetes-related, or family characteristics. Methods Data were drawn from a multi-center clinical trial. Participants (N = 155) were recruited from seven pediatric diabetes clinics. Contact log data were used to quantify both number/type of contacts prior to study enrollment as well as length of time to enrollment. Families were coded as having expedited recruitment (ER) or prolonged recruitment (PR). Baseline study data were used to compare ER and PR families on sociodemographic factors, adolescent diabetes management and health status and family characteristics such as household organization and family conflict. Results Mean length of time to recruit was 6.6 months and mean number of recruitment contacts was 10.3. Thirty-nine percent of the sample were characterized as PR. These families required even higher levels of effort (mean of 9.9 months to recruit and 15.4 contacts). There were no significant between-group differences on any baseline variable for ER and PR families, with the exception of family income. Conclusions Researchers need to make persistent efforts in order to successfully enroll adolescents of color and their caregivers into clinical trials. Social determinants of health such as family resources may differentiate families with prolonged recruitment within such samples.


2017 ◽  
Vol 25 (2) ◽  
pp. 217-223 ◽  
Author(s):  
Francesca Bovis ◽  
Nicola De Stefano ◽  
Joshua R Steinerman ◽  
Volker Knappertz ◽  
Maria Pia Sormani

Background: Baseline brain volume (BV) is predictive at a group level but is difficult to interpret at the single patient level. Objective: To validate BV cutoffs able to identify clinically relevant atrophy in relapsing–remitting multiple sclerosis (RRMS) patients. Methods: The expected normalized brain volume (NBV) for each patient was calculated using RRMS patients from two phase III clinical trials, applying a linear formula developed on the baseline variable of an independent data set. The difference between these expected NBV values and those actually observed was calculated and used to categorize the patients in the low-NBV, medium-NBV, and high-NBV groups. Results: The 2-year probability of 3-month confirmed disability worsening was significantly associated with the NBV categorization ( p = 0.006), after adjusting for treatment effect. Taking the high-NBV group as a reference, the hazard ratios for the medium-NBV and low-NBV groups were 1.22 (95% confidence interval (CI): 0.85–1.76, p = 0.27) and 1.69 (95% CI: 1.11–2.57, p = 0.01), respectively. Conclusion: This study validates the use of BV cutoffs to identify clinically relevant atrophy in RRMS study by showing that the three groups classified according to the baseline NBV adjusted for the other prognostic variables have a significant prognostic impact on the risk of disability progression.


Author(s):  
Ibrahim Abubakar Sadiq ◽  
Kode Komali

The incurable lingering metabolic syndrome of diabetes mellitus is an up-surging global tricky with tremendous physical, social, mental, economics and health undesired ramifications. Three hundred and ninety four diabetic patients were measured on 4 baseline variable age (years), sex (Male=1 and Female=2), body mass index (kg/m2) and blood pressure (mmHg). Blood sugar concentration (mg/dl) represented the response variable. The basic objective of this study is to verify the clear causal risk factors of diabetes. Both Multiple Linear Regression and Stepwise Regression techniques were applied on the data and the analysis showed that Body Mass Index (kg/m2) and Blood Pressure (mmHg) are the clearest risk factors of diabetes. This justification served the same purpose in the procedure of variables selection used.


Author(s):  
P.T. Trzepacz ◽  
H. Hochstetler ◽  
S. Wang ◽  
P. Yu ◽  
M. Case ◽  
...  

BACKGROUND: Brain beta-amyloid status portends different trajectories of clinical decline. OBJECTIVE: Determine trajectories and predictive baseline variable(s). DESIGN: Longitudinal, up to 24 months. SETTING: ADNI sites. PARTICIPANTS: Healthy control (n=325), early and late mild cognitive impairment (n=279; n=372), and Alzheimer’s dementia (n=216) subjects from ADNI-1/GO/2. MEASUREMENTS: Baseline amyloid status was based on first available CSF Aβ1-42 or, [11C]PiB or [18F]florbetapir (FBP) PET. Alzheimer’s Disease Assessment Scale–Cognitive Subscale (ADAS-Cog13) and Functional Activities Questionnaire (FAQ) were co-analyzed using Growth Mixture Modeling (GMM) to define latent class trajectories for each amyloid group. Classification and Regression Tree (CART) analysis determined which variables best predicted trajectory class membership using a number of variables available to clinicians. RESULTS: GMMs found two trajectory classes (C1, C2) each for amyloid-positive (P; n=722) and negative (N; n=470) groups. Most (90%) in the negative group were C2N with mildly impaired baseline ADAS-Cog13, normal FAQ and nonprogression; 10% were C1N with moderately impaired baseline FAQ and ADAS-Cog13 and trajectory of moderately worsening scores on the FAQ. C1P (26%) had more impaired baseline FAQ and ADAS-Cog13 than C2P (74%) and a steeper declining trajectory. CART yielded 4 decision nodes (FAQ <10.5, FAQ <6.5, MMSE ≥26.5, age <75.5) in positive and 1 node (FAQ <6.5) in negative groups, with 91.4% and 92.8% accuracy for class assignments, respectively. CONSLUSIONS: The trajectory pattern of greater decline in amyloid positive subjects was predicted by greater baseline impairment of cognition and function. While most amyloid-negative subjects had nonprogression irrespective of their diagnosis, a subgroup declined similarly to the gradually declining amyloid-positive group. CART predicted likely trajectory class, with known amyloid status, using variables accessible in a clinical setting, but needs replication.


2020 ◽  
Vol 114 (4) ◽  
pp. 232-240
Author(s):  
Ahmed Cordie ◽  
Aisha Elsharkawy ◽  
Shereen Abdel Alem ◽  
Safa Meshaal ◽  
Wafaa El Akel ◽  
...  

Abstract Background Novel direct-acting antiviral agents have shown great efficacy and tolerability in HCV-monoinfected patients. However, data are lacking regarding their efficacy and safety in HIV/HCV-genotype (GT) 4-coinfected patients. Methods A single-centre, prospective study including HIV/HCV-GT 4-coinfected patients who were treated with sofosbuvir and daclatasvir (SOF/DCV) was conducted for 12 wk. Sustained virological response (SVR) at week 12 post-treatment (SVR12), adverse events (AEs) and changes in liver stiffness measurement (LSM) at SVR12 in comparison with baseline were evaluated. Results SVR12 was achieved in 46 of 50 patients (92%). No significant difference in SVR12 was noticed among patients who received antiretroviral therapy (ART) regimens compared with those who did not receive ART regimens or between those with insignificant fibrosis (&lt;F2) and those with significant fibrosis (≥F2) (p=0.9 and p=0.3, respectively). AEs occurred in 45 (90%) patients. The most frequent AEs were fatigue, headache and nausea. No treatment-related serious AEs or deaths were reported. HIV control was not compromised. LSM, fibrosis 4 score and aspartate aminotransferase-to-platelet ratio index showed a significant decrease at SVR12 when compared with baseline (p=0.0004, p=0.0003 and p&lt;0.0001, respectively). Logistic regression analysis showed no association between baseline variables and SVR12 while significant fibrosis (≥F2) was the only baseline variable that was significantly associated with improvement of LSM at SVR12. Conclusion SOF/DCV achieved a high SVR12 and was well-tolerated in HIV/HCV-GT 4-coinfected patients.


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