{"id":875,"date":"2017-12-03T10:48:29","date_gmt":"2017-12-03T01:48:29","guid":{"rendered":"https:\/\/plaza.umin.ac.jp\/~OIO\/?p=875"},"modified":"2017-12-10T06:27:07","modified_gmt":"2017-12-09T21:27:07","slug":"case-crossover-design-1","status":"publish","type":"post","link":"https:\/\/plaza.umin.ac.jp\/~OIO\/?p=875","title":{"rendered":"Case Crossover Design (1)"},"content":{"rendered":"

\u306f\u3058\u3081\u306b<\/strong><\/h2>\n

\u30b3\u30fc\u30d2\u30fc\u304c\u5fc3\u8840\u7ba1\u30a4\u30d9\u30f3\u30c8\u306b\u6709\u5bb3\u306a\u306e\u3067\u306f\u306a\u3044\u304b\u3068\u306e\u4eee\u8aac\u3092\u7814\u7a76\u3057\u305f\u3001La Vecchia\u306e\u6587\u732e1<\/sup><\/span>\u306e\u30c7\u30fc\u30bf\u3092\u3082\u3068\u306b\u3001Case Crossover Design\u306e\u624b\u6cd5\u3092\u7d39\u4ecb\u3057\u305f\u3053\u3061\u3089\u306e\u6587\u732e2<\/sup><\/span>\u306e\u30b9\u30af\u30ea\u30d7\u30c8\u3092\u307e\u3068\u3081\u3066\u307f\u307e\u3057\u305f\u3002\u624b\u6cd5\u3092\u8a66\u3059\u4f8b\u984c\u3068\u3057\u3066\u9078\u3093\u3060\u30aa\u30ea\u30b8\u30ca\u30eb\u306e\u6587\u732e1<\/sup><\/span>\u306e\u7d50\u8ad6\u306f\u5fc5\u305a\u3057\u3082\u5e83\u304f\u53d7\u3051\u5165\u308c\u3089\u308c\u3066\u3044\u308b\u3082\u306e\u3067\u306f\u306a\u3044\u3088\u3046\u3067\u3059\u3002<\/p>\n

Case Crossover Design\u3068\u306f<\/strong><\/h2>\n

\u88fd\u85ac\u5de5\u696d\u5354\u4f1a\u306e\u30bf\u30b9\u30af\u304c\u4f5c\u6210\u3057\u305f\u8cc7\u6599\u3060\u3068\u6b21\u306e\u3088\u3046\u306b\u8aac\u660e\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n

\"\"<\/p>\n

\u300c\u66dd\u9732\u304c\u30a4\u30d9\u30f3\u30c8\u306e\u767a\u751f\u306b\u53ca\u307c\u3059\u5f71\u97ff\u304c\u6295\u85ac\u5f8c\u306e\u4e00\u5b9a\u306e\u671f\u9593\u306b\u9650\u5b9a\u3055\u308c,…\u3068\u4eee\u5b9a\u3067\u304d\u308b\u72b6\u6cc1\u3067\u9069\u5fdc\u3055\u308c\u308b\u300d\u3068\u3057\u3066\u3044\u307e\u3059\u3002\u96c6\u8a08\u4e0a\u3001\u4e00\u5b9a\u671f\u9593\u3068\u305d\u308c\u4ee5\u5916\u306e\u671f\u9593\u3092\u6bd4\u8f03\u3057\u3066\u3044\u307e\u3059\u306e\u3067\u300c\u6295\u85ac\u5f8c\u306e\u4e00\u5b9a\u671f\u9593\u306b\u3053\u3068\u3055\u3089\u9ad8\u3044\u767a\u73fe\u7387\uff08\u5f37\u3044\u5f71\u97ff\uff09\u304c\u3042\u308b\u304b\u3069\u3046\u304b\u3092\u691c\u5b9a\u3057\u3066\u3044\u308b\u300d\u306e\u3067\u306f\u306a\u3044\u304b\u3068\u8a00\u3046\u6c17\u3082\u3057\u307e\u3059\u3002<\/p>\n

Modern Epidemiology by Rothman\u3067\u3082\u6b21\u306e\u3088\u3046\u306b\u8aac\u660e\u3057\u3066\u3044\u3066\u3001\u4e00\u5b9a\u306e\u4eee\u5b9a\u306e\u4e0a\u3067\u306e\u3001case\u3068control\u306e\u6bd4\u8f03\u3068\u3044\u3046\u7acb\u5834\u306e\u3088\u3046\u3067\u3059\u3002<\/p>\n

When the exposure under study is defined by proximity to an environmental source (e.g., a power line), it may be possible to construct a specular (hypothetical) control for each case by conducting a \u201cthought experiment.\u201d Either the case or the exposure source is imaginarily moved to another
\nlocation that would be equally likely were there no exposure effect; the case exposure level under this hypothetical configuration is then treated as the (matched) \u201ccontrol\u201d exposure for the case (Zaffanella et al., 1998). When the specular control arises by examining the exposure experience of the case outside of the time in which exposure could be related to disease occurrence, the result is called a case-crossover study.<\/p><\/blockquote>\n

 <\/p>\n

Case Crossover Design \u306eR\u30b3\u30fc\u30c9<\/strong><\/h2>\n

\u3068\u308a\u3042\u3048\u305a\u30b3\u30fc\u30c9\u90e8\u5206\u306f\u3053\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n

##################################
\n#
\n# Case Crossover design converted from
\n# Ann Transl Med 2016;4(18):341
\n#
\n# Example from
\n# La Vecchia and colleagues
\n# coffee intake and MI
\n# Am J Epidemiol 1989;130:481-5
\n#
\n# 12\/2\/2017 Y. Oshima
\n#
\n##################################<\/p>\n

t<-c(9,1\/3,3,22,6,7,12,5,0.5,24)
\nfrq<-c(730,365,36,1820,2920,24,730,730,3650,365)<\/p>\n

T<-365*24
\nefftime<-ifelse(t>=1,0,1)
\nrr<-sum(efftime*(T-frq))\/sum((1-efftime)*frq)
\nrr<\/p>\n

var.log<-sum(frq*(T-frq))\/(sum(efftime*(T-frq))*sum((1-efftime)*frq))
\nse.log<-sqrt(var.log)
\nlo.log<-log(rr)-1.96*se.log
\nhi.log<-log(rr)+1.96*se.log
\nlo<-exp(lo.log)
\nhi<-exp(hi.log)<\/p>\n

or<-sum(efftime*(T-frq-(1-efftime)))\/sum((1-efftime)*(frq-efftime))
\nvar.log.or<-(sum(efftime*(T-frq-1+efftime)*(efftime+ T-frq-1+efftime))\/(2*(sum(efftime*(T-frq-1+efftime)))^2))+(sum(efftime*(T-frq-1+efftime)*(1-efftime+frq-efftime)+(1-efftime)*(frq-efftime)*(efftime+(T-frq-1+efftime)))\/(2*sum(efftime*(T-frq-1+efftime))*sum((1-efftime)*(frq-efftime))))+(sum((1-efftime)*(frq-efftime)*(1-efftime+frq-efftime))\/(2*(sum((1-efftime)*(frq-efftime)))^2))
\nse.log.or<-sqrt(var.log.or)
\nlo.log.or<-log(or)-1.96*se.log.or
\nhi.log.or<-log(or)+1.96*se.log.or
\nlo.or<-exp(lo.log.or)
\nhi.or<-exp(hi.log.or)<\/p>\n

matrix<-matrix(round(c(rr,lo,hi,or,lo.or,hi.or),2),nrow=2,byrow=TRUE)
\nrownames(matrix)<-c(“RR”,”OR”)
\ncolnames(matrix)<-c(“Value”,”low 95% CI”,”high 95% CI”)
\nmatrix<\/p>\n

mat<-matrix(, nrow = T-1, ncol = 0)
\nfor (i in 1:10) {
\nif (T%%frq[i]==0) {
\nexposure<-c(rep(c(1,rep(0,T\/frq[i]-1)),frq[i]))[-T]
\n} else {
\nexposure<-c(rep(c(1,rep(0,trunc(T\/frq[i])-
\n1)),frq[i]),rep(0,T-frq[i]*trunc(T\/frq[i])))[-T]
\n}
\nmat<-cbind(mat,exposure)
\n}<\/p>\n

commat<-rbind(efftime,mat)
\nlibrary(reshape2)
\ndata.wide<-as.data.frame(commat)
\ncolnames(data.wide)<-c(1:10)
\ndata<-melt(data.wide,measure=c(1:10))
\ncolnames(data)<-c(“id”,”exposure”)
\ndata$case<-rep(c(1,rep(0,T-1)),5)
\nhead(data)<\/p>\n

library(survival)
\nmod<- clogit(case~exposure+strata(id),data)
\nsummary(mod)<\/p>\n

data$clock<-c(rep(1,T\/(365*4)),rep(2,T\/(365*4)),rep(3,T\/(365*4)),rep(4,T\/(365*4)))
\nmod.adj<- clogit(case~exposure+clock+strata(id),data)
\nsummary(mod.adj)<\/p><\/blockquote>\n

\u7d50\u679c\u306e\u7167\u5408<\/strong><\/h2>\n

Cochran-Mantel-Haenszel\u306e\u30aa\u30c3\u30ba\u6bd4<\/strong><\/h4>\n

\u8ad6\u6587\u3067\u306f\u6b21\u306e\u901a\u308a<\/p>\n

\"\"<\/p>\n

\u30b9\u30af\u30ea\u30d7\u30c8\u3092\u8d70\u3089\u305b\u308b\u3068\u3001\u4e00\u81f4\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n

\"\"<\/p>\n

Conditional logistic regression\u306e\u30aa\u30c3\u30ba\u6bd4<\/strong><\/h4>\n

\u8ad6\u6587\u3067\u306f<\/p>\n

\"\"<\/p>\n

\u30b9\u30af\u30ea\u30d7\u30c8\u3092\u8d70\u3089\u305b\u308b\u3068\u3001\u3053\u3061\u3089\u3082\u4e00\u81f4\u3057\u3066\u3044\u307e\u3059\u3002\uff08\u5f53\u305f\u308a\u524d\u304b\uff1f\uff09<\/p>\n

 <\/p>\n

\"\"<\/p>\n

\u3064\u3065\u304f<\/a><\/p>\n

\n

References:<\/h3>\n
\n
\n
\n
1.<\/div>\n
La V, Gentile A, Negri E, Parazzini F, Franceschi S. Coffee consumption and myocardial infarction in women. Am J Epidemiol<\/i>. 1989;130(3):481-485. [PubMed<\/a>]<\/span><\/div>\n<\/div>\n<\/div>\n
\n
\n
2.<\/div>\n
Zhang Z. Case-crossover design and its implementation in R. Ann Transl Med<\/i>. 2016;4(18):341. [PMC<\/a>]<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

\u306f\u3058\u3081\u306b \u30b3\u30fc\u30d2\u30fc\u304c\u5fc3\u8840\u7ba1\u30a4\u30d9\u30f3\u30c8\u306b\u6709\u5bb3\u306a\u306e\u3067\u306f\u306a\u3044\u304b\u3068\u306e\u4eee\u8aac\u3092\u7814\u7a76\u3057\u305f\u3001La Vecchia\u306e\u6587\u732e1\u306e\u30c7\u30fc\u30bf\u3092\u3082\u3068\u306b\u3001Case Crossover Design\u306e\u624b\u6cd5\u3092\u7d39\u4ecb\u3057\u305f\u3053\u3061\u3089\u306e\u6587\u732e2\u306e\u30b9\u30af\u30ea\u30d7\u30c8\u3092\u307e\u3068\u3081\u3066\u307f\u307e\u3057…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-875","post","type-post","status-publish","format-standard","hentry","category-science"],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p9b6zl-e7","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=\/wp\/v2\/posts\/875","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=875"}],"version-history":[{"count":0,"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=\/wp\/v2\/posts\/875\/revisions"}],"wp:attachment":[{"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=875"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=875"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/plaza.umin.ac.jp\/~OIO\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=875"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}