Analysis of Capsid AHFR datasets

prepare all packages

library(tidyverse)
library(readxl)
library(lsmeans)
library(lme4)
library(ggplot2)
library(lmerTest)
setwd("C:/Users/marti/OneDrive/Documents/andras/AHFR/")

Load data for AFHR and represent in a graphic

Read data and show graphics

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "AHFR")

ggplot(dts,aes(y=`Aqueous flow`,x=`Age (weeks)`,color=`ID`))+geom_point()+facet_grid(rows=vars(`Eye imaged`),cols=vars(`Group`))

ggplot(dts,aes(y=`Aqueous flow`,x=`Age (weeks)`))+facet_grid(rows=vars(`Eye imaged`),cols=vars(`Group`))+geom_point()+geom_smooth()
## `geom_smooth()` using method = 'loess' and formula 'y ~ x'

The patter over age is not clear. But we can include a linear age term and let it interact with group.

ANOVA and mean comparisons

A linear mixed model was fit that included fixed effects of group and eye and fixed age*group term plus a random term for dog to account for repeated measures.

dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Aqueous flow`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##              Sum Sq Mean Sq NumDF  DenDF F value    Pr(>F)    
## Group        78.709  78.709     1 17.789 16.2263 0.0008052 ***
## `Eye imaged`  0.544   0.544     1 50.834  0.1121 0.7391180    
## age           3.236   3.236     1 41.748  0.6672 0.4186822    
## Group:age     8.461   8.461     1 41.806  1.7442 0.1937896    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean    SE   df lower.CL upper.CL
##  MUT     3.52 0.442 23.6     2.61     4.43
##  WT      5.95 0.409 13.0     5.06     6.83
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate    SE   df t.ratio p.value
##  MUT - WT    -2.43 0.602 17.8 -4.028  0.0008 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger

Differences between WT and mut are significant.The least square mean for WT larger than the mean for mut.

Repeat for IOP

Read data and show graphics

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "IOP")

ggplot(dts,aes(y=`Average IOP`,x=`Age (weeks)`,color=`ID`))+geom_point()+facet_grid(rows=vars(`Eye imaged`),cols=vars(`Group`))

ggplot(dts,aes(y=`Average IOP`,x=`Age (weeks)`))+facet_grid(rows=vars(`Eye imaged`),cols=vars(`Group`))+geom_point()+geom_smooth()
## `geom_smooth()` using method = 'loess' and formula 'y ~ x'

Here the interaction between age and group seems to be stronger

ANOVA and mean comparisons for (IOP)

A linear mixed model was fit that included fixed effects of group and eye and fixed age*group term plus a random term for dog to account for repeated measures.

dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Average IOP`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##              Sum Sq Mean Sq NumDF  DenDF F value    Pr(>F)    
## Group        790.24  790.24     1 24.963 66.2047 1.742e-08 ***
## `Eye imaged`   0.36    0.36     1 46.460  0.0304  0.862424    
## age          116.67  116.67     1 42.557  9.7742  0.003186 ** 
## Group:age    275.25  275.25     1 42.479 23.0601 1.976e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean   SE   df lower.CL upper.CL
##  MUT     28.3 1.17 25.9     25.9     30.7
##  WT      14.1 1.30 24.2     11.4     16.8
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate   SE df t.ratio p.value
##  MUT - WT     14.2 1.75 25 8.137   <.0001 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `Average IOP` ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 438.7
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.6317 -0.3729 -0.0754  0.3606  2.9419 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 16.08    4.010   
##  Residual             11.94    3.455   
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                 Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)     28.41810    1.24120  30.70213  22.896  < 2e-16 ***
## GroupWT        -14.22967    1.74661  23.42385  -8.147 2.74e-08 ***
## `Eye imaged`OS  -0.14862    0.84936  44.94830  -0.175    0.862    
## age              0.06770    0.01314  47.20504   5.152 4.97e-06 ***
## GroupWT:age     -0.08201    0.01674  40.86180  -4.898 1.57e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.632                     
## `Eyimagd`OS -0.337  0.005              
## age          0.141 -0.094 -0.026       
## GroupWT:age -0.112 -0.023  0.025 -0.785

Confirmed: there is a significant interaction effect of age and group on IOP. However, the marginal effect of group is strong enought for the IOP to still be significantly higher in mut compared to WT.

All other variables

ACD

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "ACD")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Acd-A`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##               Sum Sq Mean Sq NumDF  DenDF F value  Pr(>F)  
## Group        0.10525 0.10525     1 20.078  0.6907 0.41571  
## `Eye imaged` 0.21214 0.21214     1 58.886  1.3921 0.24279  
## age          0.54666 0.54666     1 42.623  3.5873 0.06502 .
## Group:age    0.84865 0.84865     1 42.578  5.5690 0.02294 *
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean     SE   df lower.CL upper.CL
##  MUT     4.26 0.0654 27.1     4.12     4.39
##  WT      4.34 0.0682 15.3     4.19     4.48
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate     SE   df t.ratio p.value
##  MUT - WT  -0.0785 0.0945 20.1 -0.831  0.4157 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `Acd-A` ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 101.4
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.12797 -0.53621 -0.01017  0.72039  1.92011 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  ID       (Intercept) 0.0003677 0.01917 
##  Residual             0.1523880 0.39037 
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                 Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)     4.203772   0.079085 33.655868  53.155   <2e-16 ***
## GroupWT         0.078523   0.092332  9.579961   0.850   0.4158    
## `Eye imaged`OS  0.108971   0.090904 48.010364   1.199   0.2365    
## age             0.002291   0.000873 32.704684   2.624   0.0131 *  
## GroupWT:age    -0.002542   0.001068 26.747756  -2.380   0.0247 *  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.590                     
## `Eyimagd`OS -0.577  0.031              
## age          0.157 -0.127 -0.016       
## GroupWT:age -0.121  0.049  0.000 -0.817

CCT

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "CCT")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`CCT`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##                  Sum Sq    Mean Sq NumDF  DenDF F value Pr(>F)
## Group        0.00090908 0.00090908     1 25.816  1.9634 0.1731
## `Eye imaged` 0.00003615 0.00003615     1 43.723  0.0781 0.7812
## age          0.00014172 0.00014172     1 61.421  0.3061 0.5821
## Group:age    0.00103310 0.00103310     1 61.316  2.2313 0.1404
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean     SE   df lower.CL upper.CL
##  MUT    0.633 0.0129 25.9    0.607    0.660
##  WT     0.606 0.0144 25.7    0.576    0.636
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate     SE   df t.ratio p.value
##  MUT - WT   0.0271 0.0193 25.8 1.401   0.1731 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: CCT ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: -232.6
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.37794 -0.45812  0.04689  0.43214  2.01508 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 0.002409 0.04908 
##  Residual             0.000463 0.02152 
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                  Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     6.339e-01  1.314e-02  2.847e+01  48.252   <2e-16 ***
## GroupWT        -2.711e-02  1.933e-02  2.620e+01  -1.402    0.173    
## `Eye imaged`OS -1.498e-03  5.355e-03  4.410e+01  -0.280    0.781    
## age             7.354e-05  1.132e-04  6.805e+01   0.650    0.518    
## GroupWT:age    -2.335e-04  1.520e-04  6.148e+01  -1.536    0.130    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.652                     
## `Eyimagd`OS -0.202  0.000              
## age          0.113 -0.072 -0.035       
## GroupWT:age -0.087 -0.044  0.042 -0.745

CM-D

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "Crn diam")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Cornea diameter (mm)`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##               Sum Sq Mean Sq NumDF  DenDF F value    Pr(>F)    
## Group        0.94789 0.94789     1 26.162 10.4354 0.0033244 ** 
## `Eye imaged` 0.01545 0.01545     1 43.062  0.1700 0.6821235    
## age          1.08531 1.08531     1 68.281 11.9482 0.0009454 ***
## Group:age    0.23127 0.23127     1 68.242  2.5461 0.1151888    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean    SE   df lower.CL upper.CL
##  MUT     17.5 0.236 26.1     17.0     17.9
##  WT      16.3 0.265 26.2     15.8     16.9
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate    SE   df t.ratio p.value
##  MUT - WT     1.15 0.355 26.2 3.230   0.0033 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `Cornea diameter (mm)` ~ Group + `Eye imaged` + age * Group +  
##     (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 145.9
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.12316 -0.30230  0.06611  0.20293  2.62575 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 0.84367  0.9185  
##  Residual             0.09083  0.3014  
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                 Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)    17.478604   0.239064 23.180051  73.113  < 2e-16 ***
## GroupWT        -1.146708   0.354725 22.085339  -3.233 0.003813 ** 
## `Eye imaged`OS -0.031036   0.075199 38.732771  -0.413 0.682090    
## age             0.006309   0.001753 67.169019   3.599 0.000606 ***
## GroupWT:age    -0.003988   0.002430 68.020160  -1.641 0.105406    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.657                     
## `Eyimagd`OS -0.156 -0.001              
## age          0.096 -0.061 -0.038       
## GroupWT:age -0.073 -0.049  0.049 -0.722

AS Vol

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "AS Vol")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Vol A.S.`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##              Sum Sq Mean Sq NumDF  DenDF F value    Pr(>F)    
## Group         15143   15143     1 25.036  5.6037 0.0259614 *  
## `Eye imaged`   4670    4670     1 46.175  1.7282 0.1951325    
## age           19555   19555     1 43.492  7.2364 0.0100939 *  
## Group:age     39386   39386     1 43.410 14.5747 0.0004233 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean   SE   df lower.CL upper.CL
##  MUT      654 18.3 25.9      616      691
##  WT       589 20.4 24.4      547      631
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate   SE df t.ratio p.value
##  MUT - WT     64.9 27.4 25 2.367   0.0260 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `Vol A.S.` ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 814.9
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.10255 -0.53116 -0.05529  0.38512  2.34257 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 4043     63.59   
##  Residual             2702     51.98   
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept)    645.2372    19.3499  31.6621  33.346  < 2e-16 ***
## GroupWT        -64.8528    27.3635  24.8242  -2.370 0.025873 *  
## `Eye imaged`OS  16.8877    12.7970  45.9714   1.320 0.193482    
## age              0.8621     0.2031  49.7256   4.244 9.55e-05 ***
## GroupWT:age     -1.0116     0.2596  43.1955  -3.897 0.000334 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.634                     
## `Eyimagd`OS -0.326  0.005              
## age          0.140 -0.093 -0.027       
## GroupWT:age -0.111 -0.025  0.026 -0.783

AC Vol

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "AC Vol")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`AC Volume`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##               Sum Sq Mean Sq NumDF  DenDF F value   Pr(>F)   
## Group         7462.9  7462.9     1 24.899  3.6450 0.067827 . 
## `Eye imaged`  3563.0  3563.0     1 46.716  1.7402 0.193538   
## age          14771.8 14771.8     1 41.836  7.2148 0.010324 * 
## Group:age    24698.5 24698.5     1 41.762 12.0631 0.001211 **
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean   SE   df lower.CL upper.CL
##  MUT      471 14.8 25.9      441      502
##  WT       429 16.5 24.1      395      463
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate   SE   df t.ratio p.value
##  MUT - WT     42.3 22.1 24.9 1.909   0.0678 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `AC Volume` ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 792
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -1.85089 -0.51196 -0.06331  0.41832  2.29271 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 2522     50.22   
##  Residual             2047     45.25   
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept)    464.0964    15.7834  32.1356  29.404  < 2e-16 ***
## GroupWT        -42.2747    22.1126  24.2682  -1.912 0.067780 .  
## `Eye imaged`OS  14.7217    11.1108  46.1104   1.325 0.191702    
## age              0.6711     0.1682  47.0569   3.991 0.000229 ***
## GroupWT:age     -0.7569     0.2138  41.1023  -3.540 0.001010 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.630                     
## `Eyimagd`OS -0.347  0.006              
## age          0.142 -0.095 -0.026       
## GroupWT:age -0.113 -0.021  0.024 -0.787

Crn Vol

For all other variables, I conduct a single pass analysis, where I read data and fit the linear model described before

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "Crn Vol")
dts<-mutate(dts,age=as.numeric(`Age (weeks)`)-mean(`Age (weeks)`))
ah_lm<-lmer(`Kv-A`~Group+`Eye imaged`+age*Group+(1|ID),data=dts)
anova(ah_lm,ddf = "Kenward-Roger")
## Type III Analysis of Variance Table with Kenward-Roger's method
##               Sum Sq Mean Sq NumDF  DenDF F value    Pr(>F)    
## Group         806.72  806.72     1 25.657  9.0031 0.0059290 ** 
## `Eye imaged`   41.99   41.99     1 44.107  0.4686 0.4971906    
## age           335.02  335.02     1 57.103  3.7389 0.0581221 .  
## Group:age    1139.72 1139.72     1 56.990 12.7194 0.0007414 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
lsmeans(ah_lm,pairwise~Group)
## NOTE: Results may be misleading due to involvement in interactions
## $lsmeans
##  Group lsmean   SE   df lower.CL upper.CL
##  MUT      182 5.03 25.9      172      192
##  WT       159 5.64 25.5      148      171
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger 
## Confidence level used: 0.95 
## 
## $contrasts
##  contrast estimate   SE   df t.ratio p.value
##  MUT - WT     22.7 7.56 25.7 3.001   0.0059 
## 
## Results are averaged over the levels of: Eye imaged 
## Degrees-of-freedom method: kenward-roger
summary(ah_lm)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: `Kv-A` ~ Group + `Eye imaged` + age * Group + (1 | ID)
##    Data: dts
## 
## REML criterion at convergence: 601.2
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.66506 -0.44593 -0.00178  0.39323  1.91604 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  ID       (Intercept) 359.25   18.954  
##  Residual              89.61    9.466  
## Number of obs: 74, groups:  ID, 29
## 
## Fixed effects:
##                 Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)    181.22941    5.16386  28.14128  35.096  < 2e-16 ***
## GroupWT        -22.69283    7.55631  25.22391  -3.003 0.005957 ** 
## `Eye imaged`OS   1.61295    2.35195  43.67705   0.686 0.496469    
## age              0.17655    0.04713  65.13794   3.746 0.000383 ***
## GroupWT:age     -0.22901    0.06248  56.72089  -3.665 0.000546 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) GropWT `Ei`OS age   
## GroupWT     -0.649                     
## `Eyimagd`OS -0.225  0.001              
## age          0.120 -0.077 -0.033       
## GroupWT:age -0.094 -0.041  0.038 -0.755

Correlation analyses

This part is to explore the possibility of using other variables as proxy for predicting AHFR. First thing to do is a simple pairwise correlation.

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "ALL")
cr<-cor(dts[,10:17])
cr[8,]
##        Acd-A         Kt-A         Kd-A        Vas-A        Acv-A         Kv-A 
##  0.055433020 -0.090480892 -0.004148388  0.022395588  0.037763202 -0.029746706 
##  Average IOP Aqueous flow 
## -0.242384456  1.000000000

The correlations are extremely small. With Absolute value lower than 0.25. let’s try with a multiple regression.

dts<-read_xlsx("Fluorophotometry organized data -VR_minus glaucoma drugs.xlsx",sheet = "ALL")
dt<-dts[,10:17]
lmm<-lm(dt$`Aqueous flow`~as.matrix(dt[,1:7]))
summary(lmm)
## 
## Call:
## lm(formula = dt$`Aqueous flow` ~ as.matrix(dt[, 1:7]))
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -4.3014 -1.7701 -0.3809  0.9556  8.5702 
## 
## Coefficients: (1 not defined because of singularities)
##                                  Estimate Std. Error t value Pr(>|t|)  
## (Intercept)                      91.93976   89.68428   1.025   0.3095  
## as.matrix(dt[, 1:7])Acd-A        -3.84437    8.96234  -0.429   0.6695  
## as.matrix(dt[, 1:7])Kt-A        -88.86714   61.01096  -1.457   0.1505  
## as.matrix(dt[, 1:7])Kd-A         -3.73258    4.51044  -0.828   0.4113  
## as.matrix(dt[, 1:7])Vas-A         0.32830    0.23317   1.408   0.1644  
## as.matrix(dt[, 1:7])Acv-A        -0.34177    0.24733  -1.382   0.1722  
## as.matrix(dt[, 1:7])Kv-A               NA         NA      NA       NA  
## as.matrix(dt[, 1:7])Average IOP  -0.10898    0.04663  -2.337   0.0228 *
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 2.481 on 59 degrees of freedom
## Multiple R-squared:  0.1236, Adjusted R-squared:  0.03443 
## F-statistic: 1.386 on 6 and 59 DF,  p-value: 0.2352
pairs(dt)

This does not help either. One last thing that could be atempted is some sort of non-linear relation. But without any prior knowledge, it would be too easy to overfit the data.

We can discuss this on THU.