Calculations involving the multivariate normal and multivariate t distributions with and without truncation [0.03%]
涉及截断和非截断多元正态和多元t分布的计算
Michael J Grayling,Adrian P Mander
Michael J Grayling
In this article, we present a set of commands and Mata functions to evaluate different distributional quantities of the multivariate normal distribution and a particular type of noncentral multivariate t distribution. Specifically, their de...
Cluster randomized controlled trial analysis at the cluster level: The clan command [0.03%]
集群随机对照试验的集群水平分析： Clan Command 方法
Jennifer A Thompson,Baptiste Leurent,Stephen Nash et al.
Jennifer A Thompson et al.
In this article, we introduce a new command, clan, that conducts a cluster-level analysis of cluster randomized trials. The command simplifies adjusting for individual- and cluster-level covariates and can also account for a stratified desi...
Power and sample-size calculations for trials that compare slopes over time: Introducing the slopepower command [0.03%]
幂和样本大小计算用于比较时间斜率的试验：介绍slopepower命令
Stephen Nash,Katy E Morgan,Chris Frost et al.
Stephen Nash et al.
Trials of interventions that aim to slow disease progression may analyze a continuous outcome by comparing its change over time-its slope-between the treated and the untreated group using a linear mixed model. To perform a sample-size calcu...
artbin: Extended sample size for randomized trials with binary outcomes [0.03%]
艺术箱：具有二元结果的随机试验的扩展样本大小
Ella Marley-Zagar,Ian R White,Patrick Royston et al.
Ella Marley-Zagar et al.
We describe the command artbin, which offers various new facilities for the calculation of sample size for binary outcome variables that are not otherwise available in Stata. While artbin has been available since 2004, it has not been previ...
Ian R White,Ella Marley-Zagar,Tim P Morris et al.
Ian R White et al.
We describe a new command, artcat, that calculates sample size or power for a randomized controlled trial or similar experiment with an ordered categorical outcome, where analysis is by the proportional-odds model. artcat implements the met...
power swgee: GEE-based power calculations in stepped wedge cluster randomized trials [0.03%]
基于GEE的分阶段楔形群随机试验功效计算方法
John A Gallis,Xueqi Wang,Paul J Rathouz et al.
John A Gallis et al.
Stepped wedge cluster randomized trials are increasingly being used to evaluate interventions in medical, public health, educational, and social science contexts. With the longitudinal and crossover nature of a SW-CRT, complex analysis tech...
xtgeebcv: A command for bias-corrected sandwich variance estimation for GEE analyses of cluster randomized trials [0.03%]
_xtgeebcv：用于群组随机对照试验GEE分析的校正偏差sandwich估计量的命令_
John A Gallis,Fan Li,Elizabeth L Turner
John A Gallis
Cluster randomized trials, where clusters (for example, schools or clinics) are randomized to comparison arms but measurements are taken on individuals, are commonly used to evaluate interventions in public health, education, and the social...
Group sequential clinical trial designs for normally distributed outcome variables [0.03%]
正态分布结果变量的组序贯临床试验设计方法
Michael J Grayling,James M S Wason,Adrian P Mander
Michael J Grayling
In a group sequential clinical trial, accumulated data are analyzed at numerous time points to allow early decisions about a hypothesis of interest. These designs have historically been recommended for their ethical, administrative, and eco...
emagnification: A tool for estimating effect-size magnification and performing design calculations in epidemiological studies [0.03%]
膨胀效应：一种估计流行病学研究中效应量放大和进行设计计算的工具
David J Miller,James T Nguyen,Matteo Bottai
David J Miller
Artificial effect-size magnification (ESM) may occur in underpowered studies, where effects are reported only because they or their associated p-values have passed some threshold. Ioannidis (2008, Epidemiology 19: 640-648) and Gelman and Ca...
cvcrand and cptest: Commands for efficient design and analysis of cluster randomized trials using constrained randomization and permutation tests [0.03%]
CVCRAND和CPTEST命令：使用约束随机化和排列检验有效设计和分析集群随机试验
John A Gallis,Fan Li,Hengshi Yu et al.
John A Gallis et al.
Cluster randomized trials (CRTs), where clusters (for example, schools or clinics) are randomized to comparison arms but measurements are taken on individuals, are commonly used to evaluate interventions in public health, education, and the...