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Code.R
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library(tidyverse)
library(tidymodels)
library(haven)
library(foreign) # for read.spss
library(MASS)
library(brant) # for testing the parallel regression assumption wit the brant test by Brant (1990) (평행선 검정)
library(ggpubr) # for ggqqplot()
# devtools::install_github("kassambara/rstatix")
library(rstatix) # for rm anova and more
library(naniar) # for missing data visualizations
library(Cairo)
library(conflicted)
conflict_prefer("t_test", "rstatix")
conflict_prefer("select", "dplyr")
conflict_prefer("filter", "dplyr")
ggplot2::theme_set(theme_classic()) # change the theme of ggplot2
rct0 <- read_sav("../완료_202105~202106_수액치료효과비교/data/초기통계데이터-BE, HCO3관련변경-22번제외.sav", encoding = "latin1")
rct_names <- read.spss("../완료_202105~202106_수액치료효과비교/data/초기통계데이터-BE, HCO3관련변경-22번제외.sav", reencode = "utf-8") %>%
names
colnames(rct0) <- rct_names
# 1. loading and wrangling data -------------------------------------------
rct <- rct0 %>%
select(
# 독립변수
배정수액2,
# 반응변수
starts_with("pH_"), starts_with("BE_"), starts_with("HCO3_"), starts_with("Cl_"),
SBP_lowest, PR_lowest, Cl상승여부0hrto24hr, AKI발생여부, MAKE여부, 생존퇴원, 생존여부_6개월,
퇴원시goodCPC, goodCPC_6개월,
# 공변량
성별, 나이, initial_shockableRhythm, bystanderCPR, no_flow_time
) %>%
rowwise() %>%
mutate(
diff_pH = pH_24hr-pH_0hr,
diff_BE = BE_24hr-BE_0hr,
diff_HCO3 = HCO3_24hr-HCO3_0hr,
diff_Cl = Cl_24hr-Cl_0hr
)
glimpse(rct)
summary(rct)
rct2 <- rct %>%
mutate(
# 0: NS, 1: PS
배정수액2 = recode(as.numeric(배정수액2), `1` = "0", `2` = "1"),
# 0: 하락, 1: 변화없음, 2: 상승
Cl상승여부0hrto24hr = recode(as.numeric(Cl상승여부0hrto24hr),
`1` = "0", `2` = "1", `3` = "2"),
# 0: 발생안함, 1: 발생
AKI발생여부 = as.numeric(AKI발생여부) %>% as.character,
# 0: 발생안함, 1: 발생
MAKE여부 = as.numeric(MAKE여부) %>% as.character,
# 0: 생존, 1: 퇴원
생존퇴원 = recode(as.numeric(생존퇴원), `1` = "0", `2` = "1"),
# 0: 생존, 1:사망
생존여부_6개월 = as.numeric(생존여부_6개월),
# 0: shockable, 1: nonshockable
initial_shockableRhythm = recode(as.numeric(initial_shockableRhythm),
`1` = "0", `2` = "1"),
# 0: 유, 1: 무, 2: 모름
bystanderCPR = recode(as.numeric(bystanderCPR),
`1` = "0", `2` = "1", `3` = "2"))
# 2. fitting proportional odds models -------------------------------------
cut_labels <- c("little", "a little", "big")
divide_group <- function(.data, .var){
diff <- .data %>% pull({{.var}}) %>% na.omit() %>% as.numeric
.data %>%
select({{.var}}, 배정수액2,
# 공변량
성별, 나이, initial_shockableRhythm, bystanderCPR, no_flow_time) %>%
na.omit() %>%
mutate(
group = cut({{.var}},
breaks = c(min(diff), quantile(diff)[["25%"]],
quantile(diff)[["75%"]], max(diff)+0.1),
right = FALSE, labels = cut_labels, ordered_result = TRUE)
) %>%
select(group, everything())
}
rct_ph <- divide_group(rct2, diff_pH)
rct_BE <- divide_group(rct2, diff_BE)
rct_HCO3 <- divide_group(rct2, diff_HCO3)
rct_Cl <- divide_group(rct2 %>% mutate(diff_Cl = abs(diff_Cl)), diff_Cl)
rct_SBP <- divide_group(rct2, SBP_lowest) %>%
mutate(group = recode_factor(group, "little" = "low", "a little" = "medium", "big" = "high",
.ordered = TRUE))
rct_PR <- divide_group(rct2, PR_lowest) %>%
mutate(group = recode_factor(group, "little" = "low", "a little" = "medium", "big" = "high",
.ordered = TRUE))
get_stat <- function(.data, var){
.data %>%
group_by(배정수액2) %>%
summarize(
n = n(),
median = median({{var}}),
IQR = IQR({{var}}),
mean = mean({{var}})
)
}
get_stat(rct_ph, diff_pH)
get_stat(rct_BE, diff_BE)
get_stat(rct_HCO3, diff_HCO3)
get_stat(rct_Cl, diff_Cl)
get_stat(rct_SBP, SBP_lowest)
get_stat(rct_PR, PR_lowest)
## (1) pH
# get_model <- function(.data, .target){ # recipe()의 모형식에서 작동 안하는듯..
# .data %>%
# select({{.target}}, 배정수액2:low_flow_time) %>%
# recipe({{.target}} ~., data = .) %>%
# step_normalize(all_predictors(), -all_nominal()) %>%
# step_dummy(all_nominal(), -{{.target}}) %>%
# prep %>%
# juice %>%
# polr({{.target}} ~ ., data = ., Hess = TRUE)
# }
# get_model(rct_odds, group_pH)
ph <- rct_ph %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_ph <- polr(group ~ ., data = ph, Hess = TRUE)
brant(model_ph)
summary(model_ph)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = ph), model_ph)
get_odds <- function(.model){
summary_table <- coef(summary(.model))
pval <- pnorm(abs(summary_table[, "t value"]), lower.tail = FALSE)* 2
summary_table <- cbind(summary_table, "p value" = round(pval, 3))
summary_table %>%
as_tibble %>%
mutate(variables = rownames(summary_table),
odds = exp(Value),
lower_odds = exp(Value - `Std. Error`*qnorm(1-0.05/2)),
upper_odds = exp(Value + `Std. Error`*qnorm(1-0.05/2))) %>%
select(variables, everything())
}
get_odds(model_ph) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (2) BE
BE <- rct_BE %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_BE <- polr(group ~ ., data = BE, Hess = TRUE)
brant(model_BE)
summary(model_BE)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = rct_BE), model_BE)
get_odds(model_BE) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (3) HCO3
HCO3 <- rct_HCO3 %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_HCO3 <- polr(group ~ ., data = HCO3, Hess = TRUE)
brant(model_HCO3)
summary(model_HCO3)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = rct_HCO3), model_HCO3)
get_odds(model_HCO3) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (4) Cl
Cl <- rct_Cl %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_Cl <- polr(group ~ ., data = Cl, Hess = TRUE)
brant(model_Cl)
summary(model_Cl)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = rct_Cl), model_Cl)
get_odds(model_Cl) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (5) SBP_lowest
SBP <- rct_SBP %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_SBP <- polr(group ~ ., data = SBP, Hess = TRUE)
brant(model_SBP)
summary(model_SBP)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = rct_SBP), model_SBP)
get_odds(model_SBP) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (6) PR
PR <- rct_PR %>%
select(group, 배정수액2:no_flow_time) %>%
recipe(group ~., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -group, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2))
model_PR <- polr(group ~ ., data = PR, Hess = TRUE)
brant(model_PR)
summary(model_PR)
# Check the Overall Model Fit
anova(polr(group ~ 1, data = rct_PR), model_PR)
get_odds(model_PR) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
# 3. fitting logistic regression models -------------------------------------
## (1) AKI 발생여부
rct_AKI <- rct2 %>%
select(AKI발생여부, 배정수액2, 성별:no_flow_time)
model_AKI <- rct_AKI %>%
recipe(AKI발생여부 ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -AKI발생여부, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2)) %>%
glm(AKI발생여부 ~ ., family = binomial, data = .)
get_odds <- function(.model){
summary_table <- coef(summary(.model))
pval <- pnorm(abs(summary_table[, "z value"]), lower.tail = FALSE)* 2
summary_table <- cbind(summary_table, "p value" = round(pval, 3))
summary_table %>%
as_tibble %>%
mutate(variables = rownames(summary_table),
odds = exp(Estimate),
lower_odds = exp(Estimate - `Std. Error`*qnorm(1-0.05/2)),
upper_odds = exp(Estimate + `Std. Error`*qnorm(1-0.05/2))) %>%
select(variables, everything())
}
get_odds(model_AKI) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (2) MAKE 여부
rct_MAKE <- rct2 %>%
select(MAKE여부, 배정수액2, 성별:no_flow_time)
model_MAKE <- rct_MAKE %>%
recipe(MAKE여부 ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -MAKE여부, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2)) %>%
glm(MAKE여부 ~ ., family = binomial, data = .)
get_odds(model_MAKE) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (3) 생존퇴원: MAKE 여부와 정확하게 동일한 분포.
rct_surv <- rct2 %>%
select(생존퇴원, 배정수액2, 성별:no_flow_time)
model_surv <- rct_surv %>%
recipe(생존퇴원 ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -생존퇴원, -배정수액2) %>%
prep %>%
juice %>%
mutate(배정수액2 = as.numeric(배정수액2)) %>%
glm(생존퇴원 ~ ., family = binomial, data = .)
get_odds(model_surv) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
identical(rct_surv %>% pull(생존퇴원), rct_MAKE %>% pull(MAKE여부))
## (4) 생존여부_6개월
rct_6surv <- rct2 %>%
select(생존여부_6개월, 배정수액2, 성별:no_flow_time)
model_6surv <- rct_6surv %>%
recipe(생존여부_6개월 ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -생존여부_6개월, -배정수액2) %>%
prep %>%
juice %>%
mutate(생존여부_6개월 = 생존여부_6개월-1,
배정수액2 = as.numeric(배정수액2)) %>%
glm(생존여부_6개월 ~ ., family = binomial, data = .)
get_odds(model_6surv) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (5) 퇴원시goodCPC
rct_CPC <- rct2 %>%
select(퇴원시goodCPC, 배정수액2, 성별:no_flow_time)
model_CPC <- rct_CPC %>%
recipe(퇴원시goodCPC ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -퇴원시goodCPC, -배정수액2) %>%
prep %>%
juice %>%
mutate(퇴원시goodCPC = 퇴원시goodCPC-1,
배정수액2 = as.numeric(배정수액2)) %>%
glm(퇴원시goodCPC ~ ., family = binomial, data = .)
get_odds(model_CPC) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
## (6) goodCPC_6개월
rct_6CPC <- rct2 %>%
select(goodCPC_6개월, 배정수액2, 성별:no_flow_time)
model_6CPC <- rct_6CPC %>%
recipe(goodCPC_6개월 ~ ., data = .) %>%
step_normalize(all_predictors(), -all_nominal()) %>%
step_dummy(all_nominal(), -goodCPC_6개월, -배정수액2) %>%
prep %>%
juice %>%
mutate(goodCPC_6개월 = goodCPC_6개월-1,
배정수액2 = as.numeric(배정수액2)) %>%
glm(goodCPC_6개월 ~ ., family = binomial, data = .)
get_odds(model_6CPC) %>%
filter(variables == "배정수액2") %>%
select(`variables`, `p value`:upper_odds)
# 4. repeated measures with linear mixed models ------------------------------------------
glimpse(rct)
## (1) pH
repeated_pH <- rct %>%
rename(treatment = 배정수액2) %>%
select(treatment:pH_24hr)
CairoWin()
gg_miss_var(repeated_pH)
plot_miss_case <- function(.data){
miss_case_summary(.data) %>%
filter(n_miss > 0) %>%
ggplot(aes(x = fct_reorder(factor(case), n_miss), y = n_miss)) +
geom_bar(stat = "identity") +
labs(x = "Case number", y = "The number of missing values") +
coord_flip()
}
CairoWin()
plot_miss_case(repeated_pH)
ph <- repeated_pH %>%
pivot_longer(pH_0hr:pH_24hr, "time") %>%
mutate(
time = recode(time, pH_0hr = "t1", pH_30min = "t2", pH_1hr = "t3", pH_2hr = "t4",
pH_4hr = "t5", pH_6hr = "t6", pH_12hr = "t7", pH_18hr = "t8", pH_24hr = "t9")
) %>%
rename(concetration = value) %>%
arrange(time, treatment) %>%
mutate(id = rep(c(1:27, 28:53), 9)) %>%
select(id, everything()) %>%
mutate_at(vars(id:time), factor)
### summary statistics
ph %>%
drop_na() %>%
group_by(treatment, time) %>%
get_summary_stats(concetration, type = "mean_se") %>%
arrange(time)
## lmm
fit <- lmerTest::lmer(concetration ~ time * treatment + (1|id), data = ph %>% drop_na())
fit
anova(fit)
#### 시간에 대한 사후 분석
ph %>%
pairwise_t_test(
concetration ~ time, paired = TRUE,
p.adjust.method = "bonferroni"
) %>%
filter(p.adj <=0.05)
## (2) Base excess
repeated_BE <- rct %>%
rename(treatment = 배정수액2) %>%
select(treatment, starts_with("BE_"))
CairoWin()
gg_miss_var(repeated_BE)
CairoWin()
plot_miss_case(repeated_BE)
BE <- repeated_BE %>%
pivot_longer(BE_0hr:BE_24hr, "time") %>%
mutate(
time = recode(time, BE_0hr = "t1", BE_30min = "t2", BE_1hr = "t3", BE_2hr = "t4",
BE_4hr = "t5", BE_6hr = "t6", BE_12hr = "t7", BE_18hr = "t8", BE_24hr = "t9")
) %>%
rename(concetration = value) %>%
arrange(time, treatment) %>%
mutate(id = rep(c(1:27, 28:53), 9)) %>%
select(id, everything()) %>%
mutate_at(vars(id:time), factor)
### summary statistics
BE %>%
drop_na() %>%
group_by(treatment, time) %>%
get_summary_stats(concetration, type = "mean_se") %>%
arrange(time)
## lmm
fit <- lmerTest::lmer(concetration ~ time * treatment + (1|id), data = BE %>% drop_na())
fit
anova(fit)
# 시간, 처리에 관한 효과 유의하게 존재
#### 사후 분석
BE %>%
pairwise_t_test(
concetration ~ time, paired = TRUE,
p.adjust.method = "bonferroni"
) %>%
filter(p.adj<=0.05)
BE %>%
pairwise_t_test(
concetration ~ treatment,
p.adjust.method = "bonferroni"
)
# -> 어차피 교호효과없으므로, group_by(time) 할 필요없이 다이렉트하게 비교하면 됨. 모든 포인트에서 PS의 BE가 더큼
## (3) HCO3
repeated_HCO3 <- rct %>%
rename(treatment = 배정수액2) %>%
select(treatment, starts_with("HCO3_"))
CairoWin()
gg_miss_var(repeated_HCO3)
CairoWin()
plot_miss_case(repeated_HCO3)
HCO3 <- repeated_HCO3 %>%
pivot_longer(HCO3_0hr:HCO3_24hr, "time") %>%
mutate(
time = recode(time, HCO3_0hr = "t1", HCO3_30min = "t2", HCO3_1hr = "t3", HCO3_2hr = "t4",
HCO3_4hr = "t5", HCO3_6hr = "t6", HCO3_12hr = "t7", HCO3_18hr = "t8", HCO3_24hr = "t9")
) %>%
rename(concetration = value) %>%
arrange(time, treatment) %>%
mutate(id = rep(c(1:27, 28:53), 9)) %>%
select(id, everything()) %>%
mutate_at(vars(id:time), factor)
### summary statistics
HCO3 %>%
drop_na() %>%
group_by(treatment, time) %>%
get_summary_stats(concetration, type = "mean_se") %>%
arrange(time)
## lmm
fit <- lmerTest::lmer(concetration ~ time * treatment + (1|id), data = HCO3 %>% drop_na())
fit
anova(fit)
# 시간, 처리에 관한 효과 유의하게 존재
#### 사후 분석
HCO3 %>%
pairwise_t_test(
concetration ~ time, paired = TRUE,
p.adjust.method = "bonferroni"
) %>%
filter(p.adj<=0.05)
HCO3 %>%
pairwise_t_test(
concetration ~ treatment,
p.adjust.method = "bonferroni"
)
## (4) Cl0
repeated_Cl <- rct %>%
rename(treatment = 배정수액2) %>%
select(treatment, starts_with("Cl_"))
miss_case_summary(repeated_Cl) %>%
filter(n_miss > 0)
Cl <- repeated_Cl %>%
pivot_longer(Cl_0hr:Cl_24hr, "time") %>%
mutate(
time = recode(time, Cl_0hr = "t1", Cl_6hr = "t2", Cl_12hr = "t3", Cl_18hr = "t4", Cl_24hr = "t5")
) %>%
rename(concetration = value) %>%
arrange(time, treatment) %>%
mutate(id = rep(c(1:27, 28:53), 5)) %>%
select(id, everything()) %>%
mutate_at(vars(id:time), factor)
### summary statistics
Cl %>%
group_by(treatment, time) %>%
get_summary_stats(concetration, type = "mean_se") %>%
arrange(time) %>%
pull(se) %>%
round(2)
## lmm
fit <- lmerTest::lmer(concetration ~ time * treatment + (1|id), data = Cl %>% drop_na())
fit
anova(fit)
# 시간, 처리, 교호효과에 관한 효과 유의하게 존재
#### 사후 분석
##### Simple main effect of group variable
# Pairwise comparisons between group levels
pwc <- Cl %>%
group_by(time) %>%
t_test(concetration ~ treatment) %>%
adjust_pvalue(method = "bonferroni") %>%
add_significance("p.adj")
pwc # # t1에서는 차이가 없으나, 나머지 time point에서는 차이가 있음. NS군의 Cl이 큼
##### Simple main effects of time variable
# Pairwise comparisons between group levels
one.way <- Cl %>%
group_by(treatment) %>%
anova_test(dv = concetration, wid = id, within = time) %>%
get_anova_table() %>%
adjust_pvalue(method = "bonferroni")
one.way # NS 군에서는 시간에 따른 Cl의 차이가 유의하나, PS에서는 존재하지 않음.
?pairwise_t_test